phenylephrine-hydrochloride and Swine-Diseases

Antimicrobials have been commonly used to control bacterial diseases in farm animals. The efficacy of these drugs deterred the development of other control measures, such as vaccines, which are currently getting more attention due to the increased concern about antimicrobial resistance. Glässer's disease is caused by Glaesserella (Haemophilus) parasuis and affects pork production around the world. Balance between colonization and immunity seems to be essential in disease control. Reduction in antimicrobial use in veterinary medicine requires the implementation of preventive measures, based on alternative tools such as vaccination and other strategies to guarantee a beneficial microbial colonization of the animals. The present review summarizes and discusses the current knowledge on diagnosis and control of Glässer's disease, including prospects on alternatives to antimicrobials.

Topics: Animals; Anti-Bacterial Agents; Disease Management; Haemophilus Infections; Haemophilus parasuis; Microbiota; Nose; Swine; Swine Diseases; Vaccination

Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Animals; Bacterial Proteins; Bacterial Toxins; Bacterial Typing Techniques; DNA, Bacterial; Lung; Nose; Polymerase Chain Reaction; Serotyping; Swine; Swine Diseases

Limited information is available on the transmission and spread of influenza virus in pig populations with differing immune statuses. In this study we assessed differences in transmission patterns and quantified the spread of a triple reassortant H1N1 influenza virus in naïve and vaccinated pig populations by estimating the reproduction ratio (R) of infection (i.e. the number of secondary infections caused by an infectious individual) using a deterministic Susceptible-Infectious-Recovered (SIR) model, fitted on experimental data. One hundred and ten pigs were distributed in ten isolated rooms as follows: (i) non-vaccinated (NV), (ii) vaccinated with a heterologous vaccine (HE), and (iii) vaccinated with a homologous inactivated vaccine (HO). The study was run with multiple replicates and for each replicate, an infected non-vaccinated pig was placed with 10 contact pigs for two weeks and transmission of influenza evaluated daily by analyzing individual nasal swabs by RT-PCR. A statistically significant difference between R estimates was observed between vaccinated and non-vaccinated pigs (p < 0.05). A statistically significant reduction in transmission was observed in the vaccinated groups where R (95%CI) was 1 (0.39-2.09) and 0 for the HE and the HO groups respectively, compared to an Ro value of 10.66 (6.57-16.46) in NV pigs (p < 0.05). Transmission in the HE group was delayed and variable when compared to the NV group and transmission could not be detected in the HO group. Results from this study indicate that influenza vaccines can be used to decrease susceptibility to influenza infection and decrease influenza transmission.

Topics: Animals; Antibodies, Viral; Enzyme-Linked Immunosorbent Assay; Influenza A Virus, H1N1 Subtype; Influenza Vaccines; Lung; Nose; Orthomyxoviridae Infections; Reassortant Viruses; Swine; Swine Diseases; Vaccines, Inactivated

Glaesserella parasuis (G. parasuis) is commonly located in the upper respiratory tract of pigs as an opportunistic pathogen. It can cause Glässer's disease, which leads to serious economic losses in the swine industry. The occurrence of the disease is often linked with the adhesion and colonization of the pathogen. The PilA pilus subunit is important for adhesion to the host, twitching motility, and biofilm formation in many bacteria. However, no research has focused on the function of PilA in

Topics: Animals; Antigens, Bacterial; Fimbriae, Bacterial; Haemophilus Infections; Haemophilus parasuis; Mice; Nose; Swine; Swine Diseases; Vaccines, Subunit

Bordetella bronchiseptica and Streptococcus suis are widely distributed swine pathogens. B. bronchiseptica is a primary pathogen and causes atrophic rhinitis and bronchopneumonia. S. suis is a contributing agent to porcine respiratory disease complex and causes systemic diseases including arthritis, meningitis, polyserositis, and septicemia. Colonization with B. bronchiseptica has been associated with increased colonization by other pathogenic bacteria and increased disease severity with viral and bacterial pathogens. It has also been reported to predispose cesarean derived, colostrum deprived (CDCD) piglets to S. suis systemic disease. Here, we evaluated the role of B. bronchiseptica colonization on S. suis colonization, dissemination, and disease in one study using conventional pigs and another using CDCD pigs. Pigs were challenged with S. suis, B. bronchiseptica, or B. bronchiseptica followed by S. suis. Incidence of S. suis disease was not increased in either study for animals pre-inoculated with B. bronchiseptica. Nasal colonization with S. suis was increased in coinfected animals, while B. bronchiseptica was similar between mono- and co-infected animals. Although increased S. suis disease was not seen in coinfected pigs, there is evidence that B. bronchiseptica can increase colonization with S. suis, which may contribute to enhanced disease when animals are stressed or immunocompromised.

Topics: Animals; Bacteria; Bordetella bronchiseptica; Bordetella Infections; Female; Nose; Pregnancy; Streptococcus suis; Swine; Swine Diseases

Reducing zoonotic influenza A virus (IAV) risk in the United States necessitates mitigation of IAV in exhibition swine. We evaluated the effectiveness of shortening swine exhibitions to <72 hours to reduce IAV risk. We longitudinally sampled every pig daily for the full duration of 16 county fairs during 2014-2015 (39,768 nasal wipes from 6,768 pigs). In addition, we estimated IAV prevalence at 195 fairs during 2018-2019 to test the hypothesis that <72-hour swine exhibitions would have lower IAV prevalence. In both studies, we found that shortening duration drastically reduces IAV prevalence in exhibition swine at county fairs. Reduction of viral load in the barn within a county fair is critical to reduce the risk for interspecies IAV transmission and pandemic potential. Therefore, we encourage fair organizers to shorten swine shows to protect the health of both animals and humans.

Topics: Animals; Humans; Influenza A virus; Influenza, Human; Nose; Orthomyxoviridae Infections; Prevalence; Swine; Swine Diseases; United States

Recently, a novel PCV species (PCV3) has been detected in cases associated with sow mortality, lesions consistent with porcine dermatitis and nephropathy syndrome, reproductive failure and multisystemic inflammation. The pathogenesis and clinical significance of PCV3 is still unclear. In this study, we investigated the immunopathogenesis of PCV3 in CD/CD pigs. Four treatment groups, PCV3 (

Topics: Animals; Antibodies, Viral; Circoviridae Infections; Circovirus; Immunoglobulin G; Inflammation; Nose; Swine; Swine Diseases; Viremia; Virus Replication; Virus Shedding

Drivers of pig trucks constitute a potential route of human transmission of livestock-associated methicillin-resistant Staphylococcus aureus clonal complex 398 (LA-MRSA CC398). In this study, we determined MRSA prevalence in pig truck drivers (

Topics: Adolescent; Adult; Agriculture; Animals; Female; Humans; Male; Methicillin-Resistant Staphylococcus aureus; Microbiota; Middle Aged; Motor Vehicles; Nose; RNA, Ribosomal, 16S; Staphylococcal Infections; Swine; Swine Diseases; Young Adult

Glaesserella (formerly Haemophilus) parasuis causes Glässer's disease, which results in high economic loss in the swine industry. To understand the polymicrobial interactions of G. parasuis and the nasal microbiota, the statistical association patterns of nasal colonizing bacteria with virulent and non-virulent strains of G. parasuis were studied accounting for the farm management practices as potential risk factors for the occurrence of Glässer's disease. The nasal microbiota from 51 weaned-piglets from four farms with Glässer's disease and three farms with no respiratory diseases was previously characterized and included in this study. The presence of virulent and/or non-virulent G. parasuis strains in the nasal cavities was determined in order to establish the potential association with other members of the nasal microbiota. Multivariate logistic and linear regression models were performed among the various members of nasal microbiota and G. parasuis. The multi-site production system and disease presence in the farm were both significantly associated with the presence of G. parasuis virulent strains in the nose of the piglets. Differential bacterial associations were observed with virulent or non-virulent G. parasuis. Chitinophagaceae, Corynebacteriaceae and Corynebacterium were positively associated with the virulent G. parasuis strains, while Enterobacteriaceae, Peptostreptococcaceae, Clostridium XI, and Escherichia/Shigella were negatively associated with virulent G. parasuis. On the other hand, Flavobacteriaceae, Planobacterium, and Phascolarctobacterium were positively associated with the non-virulent G. parasuis strains, while Rikenellaceae, Enterococcaceae, Odoribacter, and Corynebacterium were negatively associated with non-virulent G. parasuis. In conclusion, the nasal microbiota communities showed variations in the association with the G. parasuis strains type.

Topics: Animals; Haemophilus Infections; Haemophilus parasuis; Microbiota; Nose; Swine; Swine Diseases; Virulence; Weaning

Topics: Age Factors; Animals; Clostridioides difficile; Clostridium Infections; Feces; Nose; Rectum; Swine; Swine Diseases; Weaning

Wild boar is an important reservoir of. TB diagnosis and. DNA from. Measures aiming to control these factors could be useful to reduce

Topics: Animals; Coinfection; Disease Reservoirs; Female; Male; Mycobacterium bovis; Nose; Spain; Sus scrofa; Swine; Swine Diseases; Tuberculosis

In 2016, very high rates of methicillin-resistant Staphylococcus aureus (MRSA)-ST398 (99%) were found in Portuguese pig farms that used colistin, amoxicillin, and zinc oxide as feed additives. Since then, farms A and B banned the use of colistin, and farm C banned the use of both antibiotics.. The aim of the present study was to evaluate the impact of the ban of colistin and amoxicillin on pig MRSA carriage rates, clonal types and antimicrobial resistance, compared to the results obtained in 2016.. In 2018, 103 pigs (52 from farm B using amoxicillin only as a feed additive and 51 from farm C where no antibiotics were included in the feed regimen) were nasally swabbed for MRSA colonization. Isolates were tested for antimicrobial susceptibility, and characterised by spa typing, SCCmec typing and MLST. Whole genome sequencing (WGS) was performed for representative isolates.. Overall, 96% of the pigs swabbed in 2018 carried MRSA, mostly ST398-SCCmec V-spa types t011/t108. MRSA from pigs not receiving antibiotics in the feed regimen showed susceptibility to a higher number of antibiotics, namely erythromycin, ciprofloxacin, gentamicin, and chloramphenicol. Notably, most of these isolates (n = 52) presented an unusual erythromycin-susceptibility/clindamycin-resistance phenotype. WGS showed that these isolates lacked the erm and the lnu genes encoding resistance to macrolides and lincosamides, respectively, but carried the vgaALC gene encoding resistance to lincosamides, which is here firstly identified in S. aureus ST398.. After two years the ban of colistin and amoxicillin as feed additives had no significant impact on the MRSA nasal carriage rates. Nevertheless, the MRSA strains circulating in those farms showed resistance to a lower number of antibiotic classes.

Topics: Amoxicillin; Animal Feed; Animals; Anti-Bacterial Agents; Carrier State; Colistin; Drug Resistance, Multiple, Bacterial; Farms; Methicillin-Resistant Staphylococcus aureus; Nose; Portugal; Staphylococcal Infections; Swine; Swine Diseases; Whole Genome Sequencing

Influenza B viruses (IBVs) have never been isolated from natural-infected pigs in clinical cases, although the susceptibility of domestic pigs to experimental IBV infections had been confirmed as well as IBV-specific antibodies were detected from pigs under natural and experimental conditions.. We aimed to assess and investigate the activities for infection and circulation of IBVs in pigs.. Annual active surveys for influenza have been implemented on swine populations in Taiwan since July 1998. Nasal swabs, trachea, lungs, and blood from pigs were tested using virological and serological assays for influenza. Gene sequences of influenza viral isolates were determined and characterized. Preliminary sero-epidemiological data for influenza virus were investigated.. Three strains of IBV were isolated and identified from natural-infected pigs in 2014. Genetic characterization revealed the highest identities (>99%) of molecular sequence with the contemporary IBVs belonged to the B/Brisbane/60/2008 genetic clade of Victoria lineage in the phylogenetic trees for all 8 genes. IBV-specific antibodies were detected in 31 (0.2%; 95%CI: 0.1%-0.2%) of 15 983 swine serum samples from 29 (2.8%; 95%CI: 1.9%-3.9%) of 1039 farm visits under annual active surveys from 2007 through 2017. Seropositive cases have been found sparsely in 1-5 of test prefectures every year except 2015 and 2017 as well as scattered loosely over 26 townships/districts of 11 prefectures in Taiwan cumulatively in 11 years.. Influenza B viruse infections from humans to pigs remained sporadic and accidental currently in Taiwan but might have paved potential avenues for newly emerging zoonotic influenza in the future.

Topics: Animals; Antibodies, Viral; Farms; Influenza B virus; Nose; Orthomyxoviridae Infections; Phylogeny; Serologic Tests; Sus scrofa; Swine; Swine Diseases; Taiwan; Virus Replication

Colonization by livestock-associated MRSA (LA-MRSA) has increasingly been reported in the swine population worldwide. The aim of this study was to assess the prevalence of MRSA nasal carriage in healthy pigs, including the black (Calabrese) breed, from farms in the Calabria Region (Southern Italy). Between January and March 2018, a total of 475 healthy pigs reared in 32 farms were sampled by nasal swabbing. MRSA isolates were characterized by spa, MLST and SCCmec typing, and susceptibility testing to 17 antimicrobials.. 22 of 32 (66.8%) pig farms resulted positive for MRSA. The prevalence of MRSA was 46.1% (219 MRSA culture-positive out of 475 samples). MRSA colonization was significantly higher in intensive farms and in pigs with a recent or ongoing antimicrobial treatment. All 219 MRSA isolates were assigned to ST398. The most common spa types were t011 (37.0%), t034 (22.4%) and t899 (15.1%). A novel spa type (t18290) was detected in one isolate. An insertion of IS256 in the ST398-specific A07 fragment of the SAPIG2195 gene was detected in 10 out of 81 t011 isolates. Nearly all isolates carried the SCCmec type V element, except 11 isolates that carried the SCCmec type IVc. None of the isolates was positive for the Panton-Valentine leukocidin. All isolates were resistant to tetracycline. High resistance rates were also found for clindamycin (93.1%), trimethoprim/sulfamethoxazole (68.4%), fluoroquinolones (47.9-65.3%) and erythromycin (46.1%). None of the isolates was resistant to vancomycin and fusidic acid. Overall, a multidrug resistant phenotype was observed in 88.6% of isolates.. We report a high prevalence of MRSA among healthy swine in Southern Italy farms, with higher isolation frequency associated with intensive farming. The epidemiological types identified in our study reflect those reported in other European countries. Our findings underscore the importance of monitoring the evolution of LA-MRSA in pig farms in order to implement control measures and reduce the risk of spread in the animal population.

Topics: Animals; Anti-Bacterial Agents; Bacterial Typing Techniques; Carrier State; Cross-Sectional Studies; DNA, Bacterial; Drug Resistance, Bacterial; Farms; Italy; Livestock; Methicillin; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Multilocus Sequence Typing; Nose; Prevalence; Staphylococcal Infections; Swine; Swine Diseases; Tetracycline

Topics: Abattoirs; Animals; Anti-Bacterial Agents; Carrier State; China; Farms; Haemophilus Infections; Haemophilus parasuis; Microbial Sensitivity Tests; Nose; Polymerase Chain Reaction; Prevalence; Serogroup; Swine; Swine Diseases; Weaning

This work was focused to determine the prevalence and the species diversity of coagulase-negative staphylococci (CoNS) in wild boars, and to study their antimicrobial resistance phenotype and genotype. Nasal samples of 371 wild boars from six Spanish regions were collected for CoNS recovery. The identification was performed by MALDI-TOF mass-spectrometry. Antimicrobial susceptibility for eight antimicrobial agents was studied by disc-diffusion method and the presence of 31 antimicrobial resistance genes by PCR. CoNS were detected in nasal samples of 136/371 animals tested (36.6%), and 161 isolates were obtained (1-3/animal); a high diversity of species was found (n = 17), with predominance of S. sciuri (n = 64), S. xylosus (n = 21) and S. chromogenes (n = 17). Among CoNS isolates, 22.4% showed resistance to at least one antimicrobial tested. Tetracycline-resistance phenotype was the most frequently detected (10.5%), generally mediated by tet(K) gene [associated or not with tet(L)]. Other relevant resistance genes were identified including unusual ones [mecA, erm(B), erm(F), mphC, erm(43), msr(A)/msr(B), lnu(A), dfrG, fexA, and cat

Topics: Animals; Anti-Bacterial Agents; Coagulase; Drug Resistance, Bacterial; Genes, Bacterial; Genetic Variation; Microbial Sensitivity Tests; Nose; Phenotype; Spain; Staphylococcal Infections; Staphylococcus; Sus scrofa; Swine; Swine Diseases

Control of Mycoplasma hyorhinis (M. hyorhinis) associated disease is currently hindered by limited knowledge of the epidemiology and ecology of this organism. A prospective longitudinal investigation was conducted to determine the dynamics of M. hyorhinis colonization in two swine production systems. In each system (A, B), 51 young sows (parities 1, 2) and 56 older sows (>parity 2) were selected at farrowing and tested by qPCR of nasal swabs and for antibodies by serum ELISA. From each sow, a piglet was randomly selected, and nasal and serum samples were collected at birth, weaning, and 10 days post-weaning. Two further samplings were performed in the nursery and finishing stages during the high-risk periods for M. hyorhinis-associated disease, and 12 pigs were euthanized and necropsied at these later sampling events. The prevalence of M. hyorhinis colonization in sows was low (<5%). No associations were found between sow parity or sow serum titer and piglet nasal colonization at either birth or weaning. In contrast to the low prevalence (0.95-2.70%) observed in piglets pre-weaning, most pigs became colonized during the first four weeks after weaning and remained positive throughout the nursery and finishing stages. The detection of M. hyorhinis in oral fluids followed similar patterns as those observed using nasal swabs. ELISA results showed decreased detection of maternal antibodies at around 3 weeks of age and a subsequent increase after natural exposure. The role of M. hyorhinis in polyserositis and arthritis was demonstrated in these two herds. Establishing the temporal dynamics of exposure and infection with M. hyorhinis in pigs will enable more strategic implementation of intervention strategies in affected herds.

Topics: Age Factors; Animals; Antibodies, Bacterial; Enzyme-Linked Immunosorbent Assay; Female; Longitudinal Studies; Mycoplasma hyorhinis; Mycoplasma Infections; Nose; Pneumonia of Swine, Mycoplasmal; Prevalence; Prospective Studies; Real-Time Polymerase Chain Reaction; Swine; Swine Diseases; Time Factors; United States; Weaning

The prevalence of nasal carrier status of methicillin-resistant Staphylococcus aureus (MRSA) in pigs has been described elsewhere, but is unknown in South Africa. To address concerns that exist regarding the zoonotic risk that carriers pose to workers, the herd-level prevalence of MRSA was determined among 25 large (> 500 sows) commercial pig herds in South Africa, representing 45% of the large commercial herds in the country. From each herd, the nasal contents of 18 finisher pigs were sampled at the abattoir, pooled into three and selectively cultured to determine the presence of MRSA. A herd was classified as MRSA-positive if one or more of the three pooled samples cultured positive. Three of the 25 herds tested positive for MRSA, equating to a 12% herd prevalence (95% CI: 7% - 23%) among South African commercial piggeries. The prevalence of nasal MRSA carriers among large commercial pig herds in South Africa was low compared to what has been reported elsewhere and suggests a relatively low zoonotic MRSA risk to workers in South African commercial piggeries and abattoirs.

Topics: Animals; Female; Methicillin-Resistant Staphylococcus aureus; Nose; Prevalence; South Africa; Staphylococcal Infections; Swine; Swine Diseases

Influenza A virus (IAV) is a zoonotic pathogen threatening animal and public health; therefore, detection and monitoring of IAV in animal populations are critical components of a surveillance program. Swine are important hosts of IAV, wherein the virus can undergo rapid evolution. Several methods (i.e., nasal swabs, nasal wipes, and oral fluids) have been used to collect samples from swine for IAV surveillance. We utilized nasal wipes made from cotton gauze and multiple, polyester or mixed polyester fabrics to compare performance in the molecular detection and isolation of IAV. In vitro experiments revealed that no polyester or mixed polyester fabric was superior to cotton gauze for molecular IAV detection; however, 3 polyester or mixed polyester fabrics yielded significantly more viable IAV than cotton. In a field trial, both cotton gauze and the polyester or mixed polyester fabric yielded similar proportions of IAV isolates from swine. The results indicate that cotton gauze remains a practical and useful material for swine nasal wipes.

Topics: Animals; Diagnostic Techniques and Procedures; Influenza A virus; Nose; Orthomyxoviridae Infections; Sentinel Surveillance; Specimen Handling; Swine; Swine Diseases

Methicillin-resistant Staphylococcus aureus (MRSA) and extended-spectrum β-lactamase (ESBL) producing enterobacteria (ESBL-E) have emerged in livestock. This study prospectively investigates the prevalence of MRSA and ESBL-E on pig farms and in nasal and stool samples from farmers and compares molecular characteristics of these ESBL-E isolates. In 2014, samples were derived at 51 pig farms in Germany. Per farm, five dust and five fecal samples were collected; one nasal and one stool sample were retrieved from farmers. ESBL-E isolates from humans and environmental isolates from the respective farms were characterized using whole genome sequencing for classical multilocus sequence typing (MLST), determination of ESBL-encoding genes and an ad hoc core genome MLST (cgMLST) analysis. MRSA and ESBL-E were detected on 49 (96%) and 31 (61%) of the farms, respectively; in most cases (59%) simultaneously. Nasal MRSA carriage was detected in 72 of 85 (84.7%) farmers and five of 84 (6.0%) farmers carried ESBL-E. ESBL-Escherichia coli isolates from farmers belonged to MLST STs/ESBL-genes ST10/CTX-M-1, ST196/TEM-52, ST278/TEM-52, ST410/CTX-M-15 and ST453/CTX-M-1. In one case, the human ESBL-E isolate was clonally identical to isolates from the farm environment; in the other four cases typing results indicated potential exchange of resistance determinants between human and environmental isolates, but, comparing the isolates within a minimum spanning tree indicated differences in cgMLST-patterns between the farms (p=0.076). This study demonstrated rectal ESBL-E carriage rates among farmers, which were similar to those in the general population. Molecular typing suggested that cross-transmission between the farmers and the farm environment is possible.

Topics: Animals; Bacterial Typing Techniques; beta-Lactamases; Enterobacteriaceae; Enterobacteriaceae Infections; Escherichia coli; Farmers; Farms; Feces; Female; Germany; Humans; Male; Methicillin-Resistant Staphylococcus aureus; Middle Aged; Multilocus Sequence Typing; Nose; Prospective Studies; Staphylococcal Infections; Swine; Swine Diseases

Topics: Animals; Communicable Diseases, Emerging; Limit of Detection; Nose; Picornaviridae; Picornaviridae Infections; Real-Time Polymerase Chain Reaction; Rectum; RNA, Viral; Sensitivity and Specificity; Swine; Swine Diseases

Swine farms provide a dynamic environment for the evolution of influenza A viruses (IAVs). The present report shows the results of a surveillance effort of IAV infection in one commercial swine farm in Argentina. Two cross-sectional serological and virological studies (n=480) were carried out in 2011 and 2012. Virus shedding was detected in nasal samples from pigs from ages 7, 21 and 42-days old. More than 90% of sows and gilts but less than 40% of 21-days old piglets had antibodies against IAV. In addition, IAV was detected in 8/17 nasal swabs and 10/15 lung samples taken from necropsied pigs. A subset of these samples was further processed for virus isolation resulting in 6 viruses of the H1N2 subtype (δ2 cluster). Pathological studies revealed an association between suppurative bronchopneumonia and necrotizing bronchiolitis with IAV positive samples. Statistical analyses showed that the degree of lesions in bronchi, bronchiole, and alveoli was higher in lungs positive to IAV. The results of this study depict the relevance of continuing long-term active surveillance of IAV in swine populations to establish IAV evolution relevant to swine and humans.

Topics: Animals; Antibodies, Viral; Argentina; Bronchopneumonia; Cross-Sectional Studies; Epidemiological Monitoring; Humans; Influenza A Virus, H1N1 Subtype; Influenza A Virus, H1N2 Subtype; Influenza, Human; Lung; Nose; Orthomyxoviridae Infections; Sus scrofa; Swine; Swine Diseases; Virus Shedding

The 2009 H1N1 pandemic emphasized a need to evaluate zoonotic transmission of influenza A in swine production. Airborne influenza A virus has been detected in swine facilities during an outbreak. However, the personal exposure of veterinarians treating infected swine has not been characterized. Two personal bioaerosol samplers, the NIOSH bioaerosol sampler and the personal high-flow inhalable sampler head (PHISH), were placed in the breathing zone of veterinarians treating swine infected with either H1N1 or H3N2 influenza A. A greater number of viral particles were recovered from the NIOSH bioaerosol sampler (2094 RNA copies/m3) compared to the PHISH sampler (545 RNA copies/m3). In addition, the majority of viral particles were detected by the NIOSH bioaerosol sampler in the >4 μm size fraction. These results suggest that airborne influenza A virus is present in the breathing zone of veterinarians treating swine, and the aerosol route of zoonotic transmission of influenza virus should be further evaluated among agricultural workers.

Topics: Aerosols; Agriculture; Air Microbiology; Animals; Environmental Monitoring; Humans; Influenza A Virus, H1N1 Subtype; Influenza A Virus, H3N2 Subtype; Influenza, Human; Mouth; Nose; Occupational Exposure; Orthomyxoviridae Infections; Real-Time Polymerase Chain Reaction; Respiration; RNA, Viral; Swine; Swine Diseases; Veterinarians

The increasing diversity of influenza strains circulating in swine herds escalates the potential for the emergence of novel pandemic viruses and highlights the need for swift development of new vaccines. Baculovirus has proven to be a flexible platform for the generation of recombinant forms of hemagglutinin (HA) including subunit, VLP-displayed, and baculovirus-displayed antigens. These presentations have been shown to be efficacious in mouse, chicken, and ferret models but little is known about their immunogenicity in pigs. To assess the utility of these HA presentations in swine, Baculovirus constructs expressing HA fused to swine IgG2a Fc, displayed in a FeLV gag VLP, or displayed in the baculoviral envelope were generated. Vaccines formulated with these antigens wer The e administered to groups of pigs who were subsequently challenged with H1α cluster H1N1 swine influenza virus (SIV) A/Swine/Indiana/1726/88. Our results demonstrate that vaccination with any of these three vaccines elicits robust hemagglutinin inhibition titers in the serum and decreased the severity of SIV-associated lung lesions after challenge when compared to placebo-vaccinated controls. In addition, the number of pigs with virus detected in the lungs and nasal passages was reduced. Taken together, the results demonstrate that these recombinant approaches expressed with the baculovirus expression vector system may be viable options for development of SIV vaccines for swine.

Topics: Animals; Antibodies, Viral; Baculoviridae; Cell Line; Hemagglutinin Glycoproteins, Influenza Virus; Influenza A Virus, H1N1 Subtype; Influenza Vaccines; Lung; Nose; Orthomyxoviridae Infections; Random Allocation; Swine; Swine Diseases; Vaccines, Subunit; Vaccines, Synthetic

Methicillin-resistant Staphylococcus aureus (MRSA) is an important colonizer in animals and an opportunistic pathogen in humans. In humans, MRSA can cause infections that might be difficult to treat because of antimicrobial resistance. The use of bacteriophages has been suggested as a potential approach for the control of MRSA colonization to minimize the-often occupational-exposure of humans. The aim of this study was to assess the efficacy of bacteriophage treatment on porcine nasal colonization with MRSA in vitro, in vivo, and ex vivo. The effectiveness of a bacteriophage combination of phage K*710 and P68 was assessed in vitro by incubating them with MRSA V0608892/1 (ST398) measuring the OD600 hourly. To study the in vivo effect, bacteriophages were administered in a gel developed for human application, which contain 109 plaque-forming units (pfu)/mL (K and P68 in a 19.25:1 ratio) for 5 days to piglets (N = 8) that were experimentally colonized with the MRSA strain. Eight piglets experimentally colonized were used as a negative control. The MRSA strain was also used to colonize porcine nasal mucosa explants and bacteriophages were applied to assess the ex vivo efficacy of treatment. Bacteriophages were effective in vitro. In vivo, sixteen piglets were colonized with MRSA but the number of CFU recovered after the application of the bacteriophages in 8 piglets was not reduced compared to the control animals (approx. 105 CFU/swab). In the ex vivo model, 108 CFU were used to establish colonization with MRSA; a reduction of colonization was not observed after application of bacteriophages. However, application of mupirocin both in vivo and ex vivo resulted in a near eradication of MRSA.. i) The MRSA strain was killed in the presence of the bacteriophages phage K*710 and P68 in vitro. ii) Bacteriophages did not reduce porcine nasal colonization in vivo or ex vivo. Physiological in vivo and ex vivo conditions may explain these observations. Efficacy in the ex vivo model matched that of the in vivo system.

Topics: Animals; Bacteriophages; Cells, Cultured; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Nasal Mucosa; Nose; Staphylococcal Infections; Swine; Swine Diseases; Treatment Outcome

Previous research on Staphylococcus aureus in pigs focused on livestock-associated methicillin-resistant S. aureus (MRSA) and had a qualitative cross-sectional design. This study aimed to elucidate the frequency, load, and stability of S. aureus nasal carriage in pigs over time and investigated possible associations between carriage and immune response. Nasal swabs were collected three times weekly from 480 tagged adult pigs in 20 Danish production farms. S. aureus and MRSA were quantified on selective media by the most-probable-number method. The levels of IgG against 10 S. aureus antigens in serum were quantified in selected pigs by a Luminex assay. All the farms were positive for S. aureus and 15 for MRSA, leading to overall prevalences of persistent and intermittent carriers and noncarriers of 24, 52, and 23%, respectively. Carriage frequency and nasal loads were significantly higher on MRSA-positive farms. Logistic-regression modeling revealed the presence of individual pigs characterized by high nasal loads (>10,000 CFU per swab) and stable carriage regardless of farm- and pen-associated factors. On the other hand, the humoral response was strongly influenced by these environmental factors. The existence of a minority of shedders contributing to maintenance of S. aureus within farms opens up new perspectives on the control of MRSA in pig farming.

Topics: Animals; Antibodies, Bacterial; Carrier State; Disease Susceptibility; Female; Male; Methicillin-Resistant Staphylococcus aureus; Nasal Mucosa; Nose; Staphylococcal Infections; Sus scrofa; Swine; Swine Diseases

Mycoplasma (M.) hyorhinis and M. hyosynoviae are pathogens known to cause disease in pigs post-weaning. Due to their fastidious nature, there is increased need for culture-independent diagnostic platforms to detect these microorganisms. Therefore, this study was performed to develop and optimize quantitative real-time PCR (qPCR) assays to rapidly detect M. hyorhinis and M. hyosynoviae in pen-based oral fluids as well as nasal and tonsillar fluids as proxies for samples used in swine herd surveillance. Two methods of genomic DNA extraction, automated versus manual, were used to compare diagnostic test performance. A wean-to-finish longitudinal study was also carried out to demonstrate the reproducibility of using pen-based oral fluids. Overall, pen-based oral and tonsillar fluids were more likely to be positive for both types of bacteria whereas only M. hyorhinis was detected in nasal fluids. DNA extraction protocols were shown to significantly influence test result. Although the initial detection time somewhat differed, both organisms were repeatedly detected in the longitudinal study. Overall, this study evaluated two qPCR methods for rapid and specific detection of either mycoplasma. Results from the present investigation can serve as a foundation for future studies to determine the prevalence of the two microorganisms, environmental load, and effectiveness of veterinary interventions for infection control.

Topics: Animals; Diagnostic Tests, Routine; Female; Longitudinal Studies; Mouth; Mycoplasma hyorhinis; Mycoplasma hyosynoviae; Mycoplasma Infections; Nose; Palatine Tonsil; Real-Time Polymerase Chain Reaction; Reproducibility of Results; Swine; Swine Diseases

Staphylococcus aureus is an important human opportunistic pathogen residing on skin and mucosae of healthy people. Pigs have been identified as a source of human colonization and infection with methicillin-resistant Staphylococcus aureus (MRSA) and novel measures are needed to control zoonotic transmission. A recent longitudinal study indicated that a minority of pigs characterized by high nasal load and stable carriage may be responsible for the maintenance of S. aureus within farms. The primary objective of the present study was to detect genetic loci associated with nasal carriage of S. aureus in Danish crossbred pigs (Danish Landrace/Yorkshire/Duroc).. Fifty-six persistent carriers and 65 non-carriers selected from 15 farms surveyed in the previous longitudinal study were genotyped using Illumina's Porcine SNP60 beadchip. In addition, spa typing was performed on 126 S. aureus isolates from 37 pigs to investigate possible relationships between host and S. aureus genotypes. A single SNP (MARC0099960) on chromosome 12 was found to be associated with nasal carriage of S. aureus at a genome-wide level after permutation testing (p = 0.0497) whereas the association of a neighboring SNP was found to be borderline (p = 0.114). Typing of S. aureus isolates led to detection of 11 spa types belonging to the three main S. aureus clonal complexes (CC) previously described in pigs (CC9, CC30 and CC398). Individual carriers often harbored multiple S. aureus genotypes and the host-pathogen interaction seems to be independent of S. aureus genotype.. Our results suggest it may be possible to select pigs genetically resistant to S. aureus nasal colonization as a tool to control transmission of livestock-associated MRSA to humans.

Topics: Animals; Carrier State; Denmark; Genome-Wide Association Study; Genotype; Nose; Polymorphism, Single Nucleotide; Quantitative Trait Loci; Staphylococcus aureus; Swine; Swine Diseases

A total of 209 Bordetella bronchiseptica (Bbr) strains isolated from pigs were examined. Phenotypic study included: biochemical characterization (motility, catalase, oxidase, urease activity, nitrate reduction and growth on MacConkey agar) and antimicrobial susceptibility (disc diffusion method). Genotypic studies based on detection of three genes encoded virulence factors, such as: flagella (fla), dermonecrotoxin (dnt), and exogenous ferric siderophore receptor (bfrZ), using PCR. Most of the Bbr strains tested had a homogeneous biochemical profile. 97.6% of them provided suitable results in biochemical tests. All Bbr isolates tested showed high resistance to penicillin (100%), linco-spectin (100%) and ceftiofur (97.9%). Over 57% and 43% of Bbr strains were resistant to ampicillin and amoxicillin, respectively. All Bbr isolates showed high sensitivity to most chemotherapeutics used such as enrofloxacin (97.9%), tetracycline (97.9%), oxytetracycline (97.9%), amoxicillin with clavulonic acid (95.8%), florfenicol (90.4%), and gentamicine (77.6%). Over of 94% of Bbr strains were moderately susceptible to norfloxacine. Molecular analysis confirmed that almost all evaluated Bbr strains (94.7%) possessed the fla gene. A lower percentage of isolates had the dnt gene (72.7%) and the lowest percentage of strains (51.7%), had the bfrZ gene.

Topics: Animals; Bordetella bronchiseptica; Bordetella Infections; Genotype; Nose; Poland; Polymerase Chain Reaction; Swine; Swine Diseases

Sporadic influenza A virus (IAV) outbreaks in humans and swine have resulted from commingling of large numbers of people and pigs at agricultural fairs in the United States. Current antemortem IAV surveillance strategies in swine require collecting nasal swabs, which entails restraining pigs with snares. Restraint is labor-intensive for samplers, stressful for pigs, and displeasing to onlookers because pigs often resist and vocalize.. To evaluate the utility of snout wipes in exhibition swine as a method to make IAV surveillance efforts less intrusive, less labor-intensive, and more widely accepted among pig owners and exhibition officials.. Three materials (rayon/polyester gauze, cotton gauze, and Swiffer(®) Sweeper dry cloths) were inoculated with IAV, and viral recoveries from these materials were quantified using qRT-PCR and TCID50 assays. In a field trial, paired cotton gauze snout wipes and gold standard polyester-tipped nasal swabs were collected from 553 pigs representing 29 agricultural fairs and the qualitative results of rRT-PCR and viral isolation were compared.. Viral recoveries from potential snout wipe materials ranged from 0.26 to 1.59 log10 TCID50 /ml less than that of the positive control in which no substrate was included; rayon/polyester gauze performed significantly worse than the other materials. In the field, snout wipes and nasal swabs had high levels of agreement for both rRT-PCR detection and virus isolation. Although further investigation and refinement of the sampling method is needed, results indicate that snout wipes will facilitate convenient and undisruptive IAV surveillance in pigs at agricultural fairs.

Topics: Animals; Diagnostic Techniques and Procedures; Female; Indiana; Influenza A virus; Male; Nose; Ohio; Orthomyxoviridae Infections; Sentinel Surveillance; Swine; Swine Diseases

Interactions between the viral surface glycoprotein haemagglutinin (HA) and the corresponding receptors on host cells is one important aspect of influenza virus infection. Mutations in HA have been described to affect pathogenicity, antigenicity and the transmission of influenza viruses. Here, we detected polymorphisms present in HA genes of two pandemic 2009 H1N1 (H1N1pdm09) isolates, A/California/04/2009 (Ca/09) and A/Mexico/4108/2009 (Mx/09), that resulted in amino acid changes at positions 186 (S to P) and 194 (L to I) of the mature HA1 protein. Although not reported in the published H1N1pdm09 consensus sequence, the P186 genotype was more readily detected in primary infected and contact-naïve pigs when inoculated with a heterogeneous mixed stock of Ca/09. Using reverse genetics, we engineered Ca/09 and Mx/09 genomes by introducing Ca/09 HA with two naturally occurring variants expressing S186/I194 (HA-S/I) and P186/L194 (HA-P/L), respectively. The Ca/09 HA with the combination of P186/L194 with either the Ca/09 or Mx/09 backbone resulted in higher and prolonged viral shedding in naïve pigs. This efficiency appeared to be more likely through an advantage in cell surface attachment rather than replication efficiency. Although these mutations occurred within the receptor-binding pocket and the Sb antigenic site, they did not affect serological cross-reactivity. Relative increases of P186 in publicly available sequences from swine H1N1pdm09 viruses supported the experimental data, indicating this amino acid substitution conferred an advantage in swine.

Topics: Animals; Gene Expression Regulation, Viral; Hemagglutinin Glycoproteins, Influenza Virus; Influenza A Virus, H1N1 Subtype; Nose; Orthomyxoviridae Infections; Polymorphism, Genetic; Swine; Swine Diseases; Virus Shedding

Methicillin-resistant Staphylococcus aureus sequence type (ST)398 is widely spread among livestock. People in contact with livestock have a higher risk of testing positive for MRSA. Several experimental settings have been described to study in vivo colonization of MRSA in pigs, each having its own limitations. The aim of this study was to develop a nose-colonization model in pigs to quantitatively study the colonization of MRSA and the co-colonization of MSSA and MRSA. Two experiments were performed: in the first experiment piglets received an intranasal inoculation with MRSA ST398, spa-type t011, and in the second experiment piglets received an intranasal inoculation with two MSSA strains (ST398, spa-type t011 and t034) and two MRSA strains (also ST398, spa-type t011 and t034) to investigate co-colonization. Colonization was quantitatively monitored for 2 weeks in both experiments. Nasal colonization was successfully established in all piglets with stable numbers of S. aureus between 10(4) and 10(6) CFU. MSSA and MRSA were able to co-colonize.

Topics: Animals; Methicillin; Methicillin-Resistant Staphylococcus aureus; Models, Animal; Nose; Staphylococcal Infections; Staphylococcus aureus; Swine; Swine Diseases

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) in livestock has refocused attention on S. aureus colonization and transmission in pigs. This study investigated the effect of the S. aureus colonization status of a sow on the colonization status of her piglets, and whether pigs carry the same strain of S. aureus throughout production. Nasal swabs were collected from the piglets of six healthy sows two days after birth and two days before and two days after they were moved into each production stage. The average prevalence of S. aureus colonization varied between 26% and 73%. The odds of being S. aureus positive were almost 12 times higher for piglets born to nasal-positive sows than for those born to nasal-negative sows, and three times higher again for piglets born to sows that were both nasal- and vaginal-positive. Isolates recovered from piglets immediately after birth were indistinguishable from those of the dam as determined by phenotypic and molecular typing, including microarray analysis and optical mapping. All isolates belonged to clonal complex 9 and the majority exhibited a novel spa type, t10449. The findings show that the S. aureus colonization status of the sow influences the colonization status of her piglets in the early production stages but strains carried by pigs change over time. Multiresistant S. aureus was detected, in particular post-weaning. Results suggest that sow status and management practices, including mixing of pigs and antimicrobial usage at weaning, should be considered when implementing control measures for S. aureus on a farm.

Topics: Animals; Female; Ireland; Longitudinal Studies; Male; Methicillin-Resistant Staphylococcus aureus; Molecular Typing; Nose; Prevalence; Staphylococcal Infections; Staphylococcus aureus; Swine; Swine Diseases; Vagina; Weaning

The probability of detecting influenza A virus (IAV) by virus isolation (VI), point-of-care (POC) antigen detection, and real-time reverse-transcription polymerase chain reaction (rRT-PCR) was estimated for pen-based oral fluid (OF) and individual pig nasal swab (NS) specimens. Piglets (n=82) were isolated for 30 days and confirmed negative for porcine reproductive and respiratory syndrome virus, Mycoplasma hyopneumoniae, and IAV infections. A subset (n=28) was vaccinated on day post inoculation (DPI) -42 and -21 with a commercial multivalent vaccine. On DPI 0, pigs were intratracheally inoculated with contemporary isolates of H1N1 (n=35) or H3N2 (n=35) or served as negative controls (n=12). OF (n=370) was collected DPI 0-16 and NS (n=924) DPI 0-6, 8, 10, 12, 14, 16. The association between IAV detection and variables of interest (specimen, virus subtype, assay, vaccination status, and DPI) was analyzed by mixed-effect repeated measures logistic regression and the results used to calculate the probability (pˆ) of detecting IAV in OF and NS over DPI by assay. Vaccination (p-value<0.0001), DPI (p-value<0.0001), and specimen-assay interaction (p-value<0.0001) were significant to IAV detection, but virus subtype was not (p-value=0.89). Vaccination and/or increasing DPI reduced pˆ for all assays. VI was more successful using NS than OF, but both VI and POC were generally unsuccessful after DPI 6. Overall, rRT-PCR on OF specimens provided the highest pˆ for the most DPIs, yet significantly different results were observed between the two laboratories independently performing rRT-PCR testing.

Topics: Animals; Influenza A Virus, H1N1 Subtype; Influenza A Virus, H3N2 Subtype; Mouth; Nose; Probability; Swine; Swine Diseases; Time Factors

MRSA CC5 spa type t002 appears to have a broad host range, has been isolated from animals and in-contact humans in Ireland and could potentially become established in pigs in Ireland. The aims of this study were to determine if MRSA CC5 spa type t002 could persist in the tissues of the porcine upper respiratory tract following intra-nasal inoculation; to determine the relative importance of environmental and animal sources of the bacterium in the transmission cycle and to determine the importance of the pharynx as a carriage site of Staphylococcus aureus and MRSA. Twelve pigs were inoculated intra-nasally with MRSA CC5 t002. After 1 or 6 days, the inoculated pigs were removed from the contaminated environment, were washed in an antiseptic solution and placed in a clean house with a group of naive pigs (in-contact group). Another group of naive pigs was placed in the contaminated environment to assess transmission from the environment (environmental group). Nasal swabs, environmental swabs and tissue samples from the upper respiratory tract were taken for MRSA culture. Infection rates were calculated for each group of exposed pigs. MRSA persisted in the pharyngeal tissues of 6 inoculated pigs for at least 30 days and higher counts of S. aureus were found in pharyngeal tissues than in other sites. In this study we were able to demonstrate the establishment of colonisation by MRSA CC5 spa type t002 in commercially sourced pigs already colonised by S. aureus; however, colonisation was sporadic despite the inoculation of large doses. Onward transmission via pig-to-pig contact or environmental contamination was possible and a significant difference was found between the proportion of pigs infected in the environmental group and the proportion infected in the in-contact group during the first 5 days. However, no significant difference was detected in overall infection rates between the 2 groups. The tissues of the pharynx were found to carry greater numbers of S. aureus than other tissues of the upper respiratory tract; therefore, pharyngeal carriage of MRSA and S. aureus in pigs may be more significant than previously thought.

Topics: Animals; Humans; Ireland; Methicillin-Resistant Staphylococcus aureus; Nose; Staphylococcal Infections; Sus scrofa; Swine; Swine Diseases

We evaluated the sensitivity of PCR on oral fluids in detecting influenza virus in vaccinated and non-vaccinated pigs.. Three-week-old influenza-free pigs were divided into three groups: (i) control, non-vaccinated, (ii) vaccinated with a commercial, heterologous vaccine, and (iii) vaccinated with an experimental, homologous vaccine. After vaccination, an influenza-infected pig was placed in contact with each of the groups. Individual nasal swabs and pen oral fluids were collected daily. Viral RNA was tested for the presence of influenza by RRT-PCR and virus isolation attempted from oral fluids. A pen was considered positive if at least one nasal swab was positive.. Based on nasal swab results, 43·8% of pens were detected positive but only 35% based on oral fluids. Overall sensitivity of oral fluids was 80%, and virus was isolated from 51% of RRT-PCR-positive oral fluids. The kappa coefficient for agreement (ĸ) between oral fluids and nasal swabs was 0·82. Among groups, ĸ was 1 (95% CI, 1-1), 0·74 (95% CI, 0·55-0·92), and 0·76 (95% CI, 0·5-1) for control, heterologous, and homologous-vaccinated groups, respectively. There was less agreement when within pen prevalence was 10% or less. Probability of detecting influenza virus in oral fluids was 99% when within pen prevalence was higher than 18% and decreased to 69% when prevalence was 9%.. Results indicated that pen-based collection of oral fluids is a sensitive method to detect influenza even when within pen prevalence is low and when pigs have been vaccinated and highlight the potential use of oral fluids for influenza surveillance.

Topics: Animals; Influenza A virus; Influenza Vaccines; Molecular Diagnostic Techniques; Nose; Orthomyxoviridae Infections; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; Saliva; Sensitivity and Specificity; Swine; Swine Diseases; Veterinary Medicine; Virology

Isolates of the A(H1N1)pdm2009 virus were first identified in asymptomatic swine in Jiangsu province, China in January 2010, indicating that the virus has retro-infected swine after circulating through humans in mainland China. The purpose of this study was to determine whether the avian-origin European H1N1 swine influenza virus (SIV) and the A(H1N1)pdm2009 virus are cocirculating in swine in Jiangsu province of China. From May 2010 to May 2011, 1,030 nasal swab samples were collected from healthy swine in Jiangsu province of China and were tested for influenza A H1N1 using reverse transcription-PCR. Fragments of the complete genomes of viruses from the samples that were positive for influenza A H1N1 were sequenced and analysed. A total of 32 avian-origin European H1N1 SIVs were isolated, and no A(H1N1)pdm2009 viruses were identified; full-length genomes of 18 strains were sequenced. The eight gene segments of some of the isolated H1N1 viruses have 99.1-99.8% sequence identity with the human A/Jiangsu/ALS1/2011(H1N1) isolates in the same region. Our study indicates that the avian-origin European H1N1 SIVs remain endemic in swine and have retro-infected humans after circulating through swine, which may present a risk factor for public health.

Topics: Animals; China; Cluster Analysis; Evolution, Molecular; Genome, Viral; Influenza A Virus, H1N1 Subtype; Molecular Sequence Data; Nose; Orthomyxoviridae Infections; Phylogeny; RNA, Viral; Sequence Analysis, DNA; Swine; Swine Diseases

This study is the first report of experimental infection and transmission of Menangle virus (MenPV) in pigs. Isolated in 1997 from piglets that were stillborn at a large commercial piggery in New South Wales, Australia, MenPV is a recently identified paramyxovirus of bat origin that causes severe reproductive disease in pigs and an influenza-like illness, with a rash, in humans. Although successfully eradicated from the infected piggery, the virus was only isolated from affected fetuses and stillborn piglets during the period of reproductive disease, and thus the mode of transmission between pigs was not established. To investigate the pathogenesis of MenPV, we undertook time-course studies in 6-week-old pigs following intranasal administration of a low-passage, non-plaque-purified isolate from the lung of an infected stillborn piglet. Viraemia was of short duration and low titre, as determined by real-time RT-PCR and virus isolation. Following an incubation period of 2-3 days, virus was shed in nasal and oral secretions, faeces and urine, typically for less than 1 week. Cessation of shedding correlated with the development of neutralizing antibodies in sera. Secondary lymphoid organs and intestine were identified, using quantitative real-time RT-PCR, as major sites of viral replication and dissemination, and this was confirmed by positive immunolabelling of viral antigen within various lymphoid tissues and intestinal epithelium. These data provide new insights into the pathogenesis of MenPV in weaned pigs, and will facilitate future control and eradication programmes should it ever re-emerge in the pig population.

Topics: Animals; Antibodies, Neutralizing; Antibodies, Viral; Bodily Secretions; Feces; Female; Intestinal Mucosa; Lymphoid Tissue; Mouth; Nose; Paramyxoviridae Infections; Paramyxovirinae; Swine; Swine Diseases; Urine; Viral Load; Viral Tropism; Viremia; Virus Shedding

Methicillin-resistant Staphylococcus aureus (MRSA) ST398 has recently been described as a zoonotic agent. Its transmission between animals seems to be a pivotal factor in its emergence and dissemination. This experimental trial was performed to describe MRSA ST398 contamination and transmission in pigs after a low dose inoculation.. Twelve specific pathogen-free (SPF) pigs were randomly divided between two separate pens. Three pigs in each pen received a nasal inoculation of 2 × 10(4) colony-forming units per animal, and three naïve pigs were left in contact with them. Every 2 days and at necropsy, different samples were screened for MRSA. It was detected in nasal swabs from five inoculated and three naïve contact pigs, as early as 1 day after inoculation. MRSA was also found in environmental wipes but never in faecal samples. At necropsy, MRSA was detected in the lymph nodes of two contact pigs and in the tonsils and lymph nodes of three inoculated pigs. Twelve other SPF pigs were included as negative control in a separate room.. This experiment showed that inoculation of a low dose of MRSA ST398 could lead to the horizontal transmission of the bacterium between pigs, the contamination of mandibular lymph nodes and the contamination of the environment without faecal carriage.. The minimal inoculated dose via nasal route to observe transmission of MRSA ST398 between pigs is equal or lower to 2 × 10(4) colony-forming units per animal, and faecal excretion seems not to be a necessary condition for horizontal transmission.

Topics: Animals; Feces; Humans; Lymph Nodes; Methicillin-Resistant Staphylococcus aureus; Nose; Specific Pathogen-Free Organisms; Staphylococcal Infections; Swine; Swine Diseases

A real-time quantitative PCR (qPCR) for detection of the apxIVA gene of Actinobacillus pleuropneumoniae was validated using pure cultures of A. pleuropneumoniae and tonsillar and nasal swabs from experimentally inoculated Caesarean-derived/colostrum-deprived piglets and naturally infected conventional pigs. The analytical sensitivity was 5colony forming units/reaction. In comparison with selective bacterial examination using tonsillar samples from inoculated animals, the diagnostic sensitivity of the qPCR was 0.98 and the diagnostic specificity was 1.0. The qPCR showed consistent results in repeatedly sampled conventional pigs. Tonsillar brush samples and apxIVA qPCR analysis may be useful for further epidemiological studies and monitoring for A. pleuropneumoniae.

Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Animals; Bacterial Proteins; Cesarean Section; Colostrum; Nose; Palatine Tonsil; Real-Time Polymerase Chain Reaction; Sensitivity and Specificity; Sequence Analysis, DNA; Swine; Swine Diseases

In order to assess the dynamics of influenza virus infection in pigs, serological and virological follow-ups were conducted in two whole batches of pigs from two different farms (F1 and F2), from 3 weeks of age until market age. Anti-swine influenza virus (SIV) antibodies (measured by ELISA and hemagglutination inhibition) and nasal virus shedding (measured by RRT-PCR and isolation in embryonated chicken eggs and MDCK cells) were carried out periodically. SIV isolates were subtyped and hemagglutinin and neuraminidase genes were partially sequenced and analyzed phylogenetically. In F1, four waves of viral circulation were detected, and globally, 62/121 pigs (51.2%) were positive by RRT-PCR at least once. All F1 isolates corresponded to H1N1 subtype although hemagglutination inhibition results also revealed the presence of antibodies against H3N2. The first viral wave took place in the presence of colostral-derived antibodies. Nine pigs were positive in two non-consecutive sampling weeks, with two of the animals being positive with the same isolate. Phylogenetic analyses showed that different H1N1 variants circulated in that farm. In F2, only one isolate, H1N2, was detected and all infections were concentrated in a very short period of time, as assumed for a classic influenza outbreak. These findings led us to propose that influenza virus infection in pigs might present different patterns, from an epidemic outbreak to an endemic form with different waves of infections with a lower incidence.

Topics: Animals; Antibodies, Viral; Dogs; Enzyme-Linked Immunosorbent Assay; Hemagglutination Inhibition Tests; Hemagglutinin Glycoproteins, Influenza Virus; Incidence; Influenza A Virus, H1N1 Subtype; Longitudinal Studies; Madin Darby Canine Kidney Cells; Molecular Sequence Data; Nose; Orthomyxoviridae Infections; Phylogeny; Polymerase Chain Reaction; Seroepidemiologic Studies; Spain; Swine; Swine Diseases; Viral Plaque Assay; Viral Proteins; Virus Shedding

Haemophilus parasuis is a colonizer of the upper respiratory tract and the causative agent of Glässer's disease in swine. This study focused on the nasal carriage of H. parasuis after treatment with marbofloxacin. Three marbofloxacin treatments (three doses of 2mg/kg body weight [bw] every 24h, two doses of 4 mg/kg bw every 48 h and 8 mg/kg bw in one single shot) were used and all of them reduce significantly (p<0.05) the nasal carriage of H. parasuis as compared to control animals. Moreover, H. parasuis was not detected in the nasal cavities of piglets after administering the highest dose. The effect of a dose of 8 mg marbofloxacin/kg bw in one shot was further studied in a farm with clinical cases of Glässer's disease using a longitudinal study. Statistically significant reduction of nasal carriage of H. parasuis was detected during the first week after treatment in comparison with the control group. However, a clear relationship between the minimum inhibitory concentration (MIC) of the different strains, their putative virulence or the treatment group (antibiotic or control) from which they were isolated was not detected. Finally, the effect induced by the antibiotic treatment on the bacterial strains seemed to be transitory, since diverse H. parasuis strains (with high and low marbofloxacin MICs) were observed 7 days after finishing the treatment.

Topics: Animals; Anti-Bacterial Agents; Fluoroquinolones; Haemophilus Infections; Haemophilus parasuis; Longitudinal Studies; Microbial Sensitivity Tests; Nose; Random Allocation; Swine; Swine Diseases

Topics: Animals; Carrier State; China; Disease Reservoirs; Female; Male; Meat; Methicillin-Resistant Staphylococcus aureus; Nose; Staphylococcal Infections; Swine; Swine Diseases; Zoonoses

Since the first report on methicillin resistant Staphylococcus aureus (MRSA) CC398 in pigs, several countries have determined the prevalence of MRSA-positive pig herds using different sampling and laboratory techniques. The objective of the study was to compare three sampling methods for MRSA-classification of herds. Therefore, nasal swabs of pigs and environmental wipes were collected from 147 herds with breeding pigs. Per herd, laboratory examination was done on 10 pools of 6 nasal swabs (NASAL), 5 single environmental wipes (ENVSINGLE) and one pool of 5 environmental wipes (ENVPOOL). Large differences in apparent prevalence of MRSA-positive herds between methods were found: 19.1% for ENVPOOL, 53.1% for ENVSINGLE, and 70.8% for NASAL. Pairwise comparisons of methods resulted in relative sensitivities of 26.9% (ENVPOOL vs. NASAL), 34.6% (ENVPOOL vs. ENVSINGLE), and 72.1% (ENVSINGLE vs. NASAL) with relative specificities of respectively 100%, 98.6% and 93.0%. Cohen's kappa was respectively 0.18, 0.32 and 0.55, thus varying between very poor and moderate agreement. Examination of environmental wipes is an easy and non-invasive method to classify herds for MRSA. The number of environmental wipes needed depends on e.g. required detection limits and within-herd prevalence. In low prevalent herds (e.g. herds with <3 positive pools of nasal swabs), 25 single environmental wipes are required to be 90% sure that MRSA is detected at a detection limit similar to analyzing 10 pools of nasal swabs. Individual analysis of environmental wipes is highly recommended, as pooling 5 environmental samples resulted in a substantial reduction of the apparent prevalence.

Topics: Animal Husbandry; Animals; Breeding; Environmental Microbiology; Epidemiologic Methods; Methicillin-Resistant Staphylococcus aureus; Nose; Prevalence; Reproducibility of Results; Sensitivity and Specificity; Staphylococcal Infections; Swine; Swine Diseases

The objective of this study was to determine the amount and infectivity of porcine circovirus type 2 (PCV2) shed in nasal, oral and fecal secretions following experimental infection. Fecal, oral and nasal swabs and blood were collected at regular intervals until 69 days post-inoculation (DPI) from five PCV2-experimentally inoculated pigs (Trial 1). To assess the infectivity of the PCV2 present in excretions, secretions, and on a hypodermic needle, 26 PCV2-naïve pigs (Trial 2) were inoculated with various samples obtained from Trial 1 pigs. In Trial 1, PCV2 DNA was detected in all sample types by 69 DPI. There were no differences in the amount of PCV2 DNA present in different sample types over time. In Trial 2, intraperitoneal inoculation with contaminated fecal, nasal and oral samples; intranasal inoculation of nasal secretions; and feces fed to naïve animals resulted in viremia and seroconversion. Viremia and microscopic lesions were noted in one animal injected using a contaminated needle. In conclusion, experimental PCV2 exposure results in a long term infection. PCV2 is shed in similar amounts by nasal, oral and fecal routes and is infectious to naïve pigs confirming that multiple routes of transmission are likely important in spread of PCV2 between pigs.

Topics: Animals; Antibodies, Viral; Circoviridae Infections; Circovirus; DNA, Viral; Feces; Immunoglobulin G; Mouth; Nose; Swine; Swine Diseases; Virus Shedding

The objective of this study was to determine the amount of porcine circovirus type 2 (PCV2) shed in nasal, oral and fecal secretions over time following natural PCV2 infection. Fecal, oral and nasal swabs and blood were collected at regular intervals starting at 28 days post-farrowing (DPF) until 209 DPF from four pigs naturally infected with PCV2. PCV2 DNA was detected in all sample types. There were no differences in the amount of PCV2 DNA present in different sample types over time. PCV2 DNA was detectable in sera and secretions in pigs through 209 DPF. Natural exposure to PCV2 results in a long term infection and PCV2 is shed in similar amounts by nasal, oral and fecal routes.

Topics: Animals; Antibodies, Viral; Circoviridae Infections; Circovirus; DNA, Viral; Feces; Immunoglobulin G; Mouth; Nose; Polymerase Chain Reaction; Swine; Swine Diseases; Virus Shedding

Topics: Animals; Nose; Rhinitis, Atrophic; Severity of Illness Index; Swine; Swine Diseases

Topics: Animal Husbandry; Animals; Anti-Bacterial Agents; Carrier State; Drug Resistance, Bacterial; Feces; Livestock; Methicillin Resistance; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Nose; Polymerase Chain Reaction; Staphylococcal Infections; Swine; Swine Diseases; Thailand

In 2005, methicillin-resistant Staphylococcus aureus was found in pig herds and in humans in contact with pigs. To determine the prevalence of, this now-called livestock-associated (LA) MRSA among pig herds in The Netherlands and to identify and quantify risk factors, an observational study of 202 pig herds was performed between 2007 and 2008. Five environmental wipes and 60 nasal swabs from each herd were collected, and microbiological analysis was performed on single environmental samples and pooled nasal samples. A herd was considered MRSA-positive if ≥1 sample tested positive. The prevalence of MRSA-positive herds was 67% in breeding herds and 71% in finishing herds. Multivariable logistic regression analysis was then performed on data from 171 breeding herds. The number of MRSA-positive herds increased from ∼30% at the start to ∼75% at the end of the study, most likely due to transmission between herds. The prevalence of MRSA increased with herd size, as ∼40% of smaller herds (<250 sows) were MRSA-positive compared to >80% of larger herds (>500 sows). Other risk factors (e.g. antimicrobial use, purchase of gilts and hygiene measures) were not significantly associated with MRSA, though associated with herd size. Herd size appeared to be a compilation of several factors, which made larger herds more often MRSA positive.

Topics: Animals; Anti-Bacterial Agents; Bacterial Typing Techniques; Environmental Microbiology; Female; Methicillin; Methicillin Resistance; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Netherlands; Nose; Prevalence; Risk Factors; Staphylococcal Infections; Sus scrofa; Swine; Swine Diseases

The Eurasian wild boar (Sus scrofa) is increasingly relevant as a host for several pathogenic mycobacteria. We aimed to characterize the first experimental Mycobacterium avium subsp. avium (MAA) infection in wild boar in order to describe the lesions and the immune response as compared to uninfected controls. Twelve 1-4-month-old wild boar piglets were housed in class III bio-containment facilities. Four concentrations of MAA suspension were used: 10, 10(2) and 10(4) mycobacteria (2 animals each, oropharyngeal route) and 2.5 x 10(6) mycobacteria (2 animals each by the oropharyngeal and nasal routes). No clinical signs were observed and pathology evidenced a low pathogenicity of this MAA strain for this particular host. Bacteriological and pathological evidence of successful infection after experimental inoculation was found for the group challenged with 2.5 x 10(6) mycobacteria. These four wild boar showed a positive IFN-gamma response to the avian PPD and the real-time RT-PCR data revealed that three genes, complement component C3, IFN-gamma and RANTES, were significantly down regulated in infected animals. These results were similar to those found in naturally and experimentally M. bovis-infected wild boar and may constitute biomarkers of mycobacterial infection in this species.

Topics: Animals; Animals, Wild; DNA Primers; Gene Expression Profiling; Interferon-gamma; Leukocytes; Mycobacterium avium; Nose; Oropharynx; Reverse Transcriptase Polymerase Chain Reaction; Spain; Swine; Swine Diseases; Tuberculosis

A total of 2,662 samples, collected from March to September 2009 in Switzerland, were tested for the presence of meticillin-resistant Staphylococcus aureus (MRSA). The collection comprised nasal swabs from 148 pig farmers, 133 veterinarians, 179 slaughterhouse employees, 800 pigs, 300 calves, 400 cattle, 100 pooled neck skin swabs from chicken carcasses, and 460 food samples of animal origin. Moreover, 142 S. aureus strains, isolated from bovine mastitis milk, were included in the study. Twenty samples (< 1%; four veterinarians, 10 pigs, three calves, one young bull, and two mastitis milk samples) tested positive for MRSA. Genotyping of the MRSA strains was performed by multilocus sequence typing, spa- and SCCmec-typing, and revealed ST398 (n=18), ST8 (n=1), ST 1 (n=1), spa types t011 (n=7), t034 (n=11), t064 (n=1), t127 (n=1), and SCCmec types IV (n=4) and V (n=16). The 20 MRSA strains were subjected to antibiotic susceptibility testing and pulsed-field gel electrophoresis using the restriction enzyme EagI. Supplementary PCR reactions were performed to investigate the presence of Panton-Valentine leukocidin and staphylococcal enterotoxins A to D.

Topics: Agriculture; Animals; Carrier State; Case-Control Studies; Cattle; Cattle Diseases; Chickens; Female; Food Contamination; Food Microbiology; Humans; Mastitis, Bovine; Meat; Methicillin Resistance; Methicillin-Resistant Staphylococcus aureus; Milk; Nose; Population Surveillance; Poultry Diseases; Prevalence; Risk Assessment; Risk Factors; Species Specificity; Staphylococcal Food Poisoning; Staphylococcal Infections; Swine; Swine Diseases; Switzerland; Veterinarians

Although pigs are susceptible to avian influenza viruses (AIV) of different subtypes, the incidence of AIV infections in the field appears to be low. Swine H1N1, H3N2 and H1N2 influenza viruses (SIV) are enzootic worldwide and most pigs have antibodies to 1 or more SIV subtypes. This study aimed to examine whether infection-immunity to H1N1 or H3N2 SIV may (1) protect pigs against subsequent infections with AIV of various haemagglutinin and/or neuraminidase subtypes and/or (2) interfere with the serological diagnosis of AIV infection by haemagglutination inhibition (HI) or virus neutralization (VN) tests. Pigs were inoculated intranasally with an H1N1 or H3N2 SIV or left uninoculated. Four or 6 weeks later all pigs were challenged intranasally with 1 of 3 AIV subtypes (H4N6, H5N2 or H7N1). Fifteen out of 17 challenge control pigs shed the respective AIV for 4-6 days post-inoculation and 16 developed HI and VN antibodies. In contrast, 28 of the 29 SIV-immune pigs did not have detectable AIV shedding. Only 12 SIV-immune pigs developed HI antibodies to the AIV used for challenge and 14 had VN antibodies. Antibody titres to the AIV were low in both control and SIV-immune pigs. Our data show that prior infection of pigs with SIV is a barrier to infection with AIV of unrelated subtypes. Serological screening in regions where SIV is enzootic is only useful when the AIV strain for which the pigs need to be tested is known.

Topics: Animals; Antibodies, Viral; Influenza A virus; Nose; Orthomyxoviridae Infections; Random Allocation; Swine; Swine Diseases

Antibiotic susceptibility of bacteria isolated from nasal swabs and lungs of pigs, to 16 commonly used antibiotics, was determined by disc diffusion test. beta-lactams showed the best activity against Streptococcus suis (S. suis) (> 99% of susceptible strains). The lowest sensitivity of S. suis was evidenced to: tylosin, tetracycline and neomycin (50%, 40% and 25%, respectively). Isolates of Escherichia coli (E. coli) demonstrated the highest susceptibility to cephalosporin (85% strains), gentamicin and norfloxacin (over 74%). The lowest susceptibility of E. coli was demonstrated to tiamulin and penicillin (11.3% and 1.9%, respectively). Over 80% of Actinobacillus pleuropneumoniae (App) strains were susceptible to all antibiotics tested. The highest resistance of App, but demonstrated by below 20% of tested isolates only, was evidenced to neomycin and LxS. Isolates of Pasteurella multocida (Pm), Haemophilus parasuis (Hps) and Arcanobacterium pyogenes (A. pyogenes) were highly susceptible to the most antibiotics included in the analysis. The comparison of the in vitro susceptibility of pathogens to the chemotherapeutics used on Polish farms for the therapy of bacterial infection of pigs within the last five years and the last 10 years, showed an increasing percent of E. coli and S. suis strains resistant to commonly used antibiotics. It is also shown that Pm, Hps, App and A. pyogenes isolates were continuously susceptible to the most chemotherapeutics applied.

Topics: Animals; Anti-Bacterial Agents; Drug Resistance, Multiple, Bacterial; Lung; Lung Diseases; Nose; Poland; Swine; Swine Diseases; Time Factors

Infection with Erysipelothrix rhusiopathiae has a significant economic impact on pig production systems worldwide. Both inactivated and attenuated vaccines are available to prevent development of clinical signs of swine erysipelas. The ability of a live attenuated E. rhusiopathiae strain to become persistently established in pigs after intranasal exposure and its potential to cause clinical signs consistent with swine erysipelas after being administered directly into the nasopharynx of healthy pigs was evaluated. Five, E. rhusiopathiae-negative pigs were vaccinated by deep intranasal inoculation then followed for 14 days. Nasal swabs were collected daily for 5 days and clinical observations were made daily for 14 days post-vaccination. Nasal swabs were cultured for E. rhusiopathiae with the intent of back-passaging any recovered organisms into subsequent replicates. No organism was recovered from nasal swabs in the first vaccination replicate. A second replicate including 10 pigs was initiated and followed in an identical manner to that described above. Again, no E. rhusiopathiae was recovered from any pigs. No pigs in either replicate showed any signs of clinical swine erysipelas. The live attenuated E. rhusiopathiae strain evaluated in this study did not appear to become persistently established in pigs post-vaccination, did not cause any local or systemic signs consistent with swine erysipelas, and was therefore unlikely to revert to a virulent state when used in a field setting.

Topics: Administration, Intranasal; Animals; Bacterial Vaccines; Body Temperature; Erysipelothrix; Erysipelothrix Infections; Nasal Mucosa; Nose; Safety; Swine; Swine Diseases; Vaccines, Attenuated; Virulence; Weight Gain

Longitudinal case-control studies were performed in post-weaning multisystemic wasting syndrome (PMWS) affected farms from Denmark and Spain using similar designs. Fourteen independent batches of 100-154 pigs per batch were monitored from birth to PMWS outbreak occurrence. Pigs displaying PMWS-like signs and matched healthy cohorts were euthanized during the clinical outbreak. PMWS was diagnosed according to internationally accepted criteria and pigs were classified as: (i) PMWS cases, (ii) wasted non-PMWS cases and (iii) healthy pigs. Porcine circovirus type 2 (PCV2) quantitative PCR (qPCR) and serology techniques were applied to analyse longitudinally collected sera and/or nasal and rectal swabs. Results showed that PCV2 load increased in parallel to waning maternal antibody levels, reaching the maximum viral load concurrent with development of clinical signs. PMWS affected pigs had higher PCV2 prevalence and/or viral load than healthy pigs in all collected samples at necropsy (p<0.0001-0.05) and even in sera and nasal swabs at the sampling prior to PMWS outbreak (p<0.01-0.05). Danish farms had a higher PCV2 prevalence in young piglets as well as an earlier PMWS presentation compared to Spanish farms. PMWS diagnoses were confirmed by laboratory tests in only half of pigs clinically suspected to suffer from PMWS. Positive and significant correlations were found among PCV2 viral loads present in sera, nasal swabs, rectal swabs and lymphoid tissues (R=0.289-0.827, p<0.0001-0.01), which indicates that nasal and rectal swabs were suitable indicators of PCV2 excretion. Sensitivity and/or specificity values observed from both tests used separately or combined suggested that qPCR and/or serology tests are not apparently able to substitute histopathology plus detection of PCV2 in tissues for the individual PMWS diagnosis within PMWS affected farms. However, qPCR appears to be a potential reliable technique to diagnose PMWS on a population basis.

Topics: Aging; Animals; Circoviridae Infections; Circovirus; Denmark; Disease Outbreaks; Nose; Polymerase Chain Reaction; Rectum; Spain; Swine; Swine Diseases; Viral Load; Wasting Syndrome; Weaning

The efficacy of recently developed porcine circovirus type 2 (PCV2) vaccines has not been tested yet against PCV2 isolates of the two proposed genotypes. In the present work, the efficacy of a subunit vaccine containing PCV2 capsid protein was evaluated by using a challenge model with four different PCV2 isolates of different genotype and geographic origin. The vaccine prevented the development of viremia in all cases as well as significantly decreased nasal and faecal shedding of the virus. Also, the vaccine elicited PCV2-specific neutralizing antibodies to PCV2 even in the presence of maternally derived immunity.

Topics: Animals; Antibodies, Viral; Capsid Proteins; Circoviridae Infections; Circovirus; Feces; Genotype; Neutralization Tests; Nose; Phylogeny; Swine; Swine Diseases; Vaccines, Subunit; Viremia; Virus Shedding

A PCR test for identification of Haemophilus parasuis was optimized using the 16S rDNA sequences of the 15 serotype reference strains of H. parasuis. The test was evaluated on a collection of 218 Danish field isolates as well as on 81 representatives of 27 other species, including genetically affiliated species within Pasteurellaceae. In addition, DNA preparations from 56 H. parasuis isolates from North America were included. To obtain a test that was specific for H. parasuis, a multiplex PCR using 3 different primers was developed. The PCR test produced an amplicon of approximately 1090 bp only with representatives of H. parasuis. The test was further evaluated on 55 clinical samples from 16 Danish pigs suspected for being infected with H. parasuis, showing polyserositis or septicemia at autopsy as well as on 492 nasal swabs. The test was compared with the performance of a PCR test earlier published by Oliveira et al. [Oliveira, S., Galina, L., Pijoan, C., 2001. Development of a PCR test to diagnose Haemophilus parasuis infections. J. Vet. Diagn. Invest. 13, 495-501]. The sensitivity of the present PCR test was found to be slightly lower when applied on clinical samples from diseased pigs and 10-fold lower when tested on pure cultures of H. parasuis (5CFU and 0.5CFU/PCR reaction, respectively). Addition of 1.4 x 10(5) Escherichia coli to each PCR tube did not alter the sensitivity of the tests. No difference in sensitivity of the tests was observed when tested on purified DNA. On the other hand, the present PCR test was found to be 100% species specific for H. parasuis, in contrast to the PCR test of Oliveira et al., which also tested positive for strains belonging to A. indolicus, A. porcinus, and A. minor, species commonly occurring in the upper respiratory tract. However, when the PCR test of Oliveira et al. is used on samples from systemic locations the chances for false positive results are apparently low. The present PCR test represents a rapid and reliable method for genetically based identification of H. parasuis. The high species specificity of the test makes it suitable for detection of H. parasuis in clinical samples, regardless of the presence of affiliated species and contaminating flora. As the two PCR tests differ in sensitivity and specificity, the use of both PCR tests for different purposes is a possibility.

Topics: Animals; Colony Count, Microbial; DNA Primers; DNA, Bacterial; DNA, Ribosomal; Haemophilus Infections; Haemophilus parasuis; Nose; Polymerase Chain Reaction; Reproducibility of Results; RNA, Ribosomal, 16S; Sensitivity and Specificity; Sequence Analysis, DNA; Serotyping; Species Specificity; Swine; Swine Diseases

Little attention has been paid to the possibility of transmission of Salmonella in intensive pig production systems through alternate methods, such as airborne or direct nose-to-nose contact. This experimental study tested the hypothesis of nose-to-nose transmission of Salmonella enterica serovars Typhimurium (Trial I) and Agona (Trial II) in weaned pigs using stainless steel/glass isolation cabinets. In each trial, cabinet 1 (control pigs) and cabinet 2 (sentinel pigs) were connected directly to the fan unit. Cabinet 3 (seeded pigs) was not directly linked to the fan, but was arranged to receive a constant unidirectional airflow from cabinet 2 (sentinel pigs) through a 10cm diameter hole, which also allowed nose-to-nose contact between pigs housed in these two cabinets. Air was taken out of the system through ducts connecting cabinets 1 and 3 to the exhauster. Therefore, direct contact among seeded and sentinel pigs was allowed but possible aerial transference of contaminated particles between those cabinets was prevented. The system was opened 21 days post-inoculation and tissue samples were collected for bacteriological analysis. The recovery of nalidixic acid-resistant Salmonella Typhimurium from sentinel pigs corroborates the hypothesis of nose-to-nose transmission of that pathogen in pigs. However, serovar-related differences might exist regarding the nose-to-nose transmissibility of Salmonella in pigs, since Salmonella Agona was not detected in sentinel pigs (Trial II).

Topics: Animals; Disease Transmission, Infectious; Male; Nose; Salmonella Infections, Animal; Salmonella typhimurium; Swine; Swine Diseases

Haemophilus parasuis is the aetiological agent of Glässer's disease in swine. In addition, this bacterium causes other clinical outcomes and can also be isolated from the upper respiratory tract of healthy pigs. Isolates of H. parasuis differ in phenotypic features (e.g. protein profiles, colony morphology or capsule production) and pathogenic capacity. Differences among strains have also been demonstrated at the genetic level. Several typing methods have been used to classify H. parasuis field strains, but they had resolution or implementation problems. To overcome these limitations, a multilocus sequence typing (MLST) system, using partial sequences of the house-keeping genes mdh, 6pgd, atpD, g3pd, frdB, infB and rpoB, was developed. Eleven reference strains and 120 field strains were included in this study. The number of alleles per locus ranged from 14 to 41, 6pgd being the locus with the highest diversity. The high genetic heterogeneity of this bacterium was confirmed with MLST, since the strains were divided into 109 sequence types, and only 13 small clonal complexes were detected by the Burst algorithm. Further analysis by unweighted-pair group method with arithmetic mean (UPGMA) identified six clusters. When the clinical background of the isolates was examined, one cluster was statistically associated with nasal isolation (putative non-virulent), while another cluster showed a significant association with isolation from clinical lesions (putative virulent). The remaining clusters did not show a statistical association with the clinical background of the isolates. Finally, although recombination among H. parasuis strains was detected, two divergent branches were found when a neighbour-joining tree was constructed with the concatenated sequences. Interestingly, one branch included almost all isolates of the putative virulent UPGMA cluster.

Topics: Alleles; Animals; Bacterial Proteins; Bacterial Typing Techniques; Cluster Analysis; DNA, Bacterial; Genetic Heterogeneity; Genotype; Haemophilus Infections; Haemophilus parasuis; Molecular Epidemiology; Molecular Sequence Data; Nose; Sequence Analysis, DNA; Statistics as Topic; Swine; Swine Diseases

We conducted a study among a group of 26 regional pig farmers to determine the methicillin-resistant Staphylococcus aureus prevalence rate and found it was >760 times greater than the rate of patients admitted to Dutch hospitals. While spa-type t108 is apparently a more widespread clone among pig farmers and their environment, we did find other spa-types.

Topics: Agriculture; Animals; Carrier State; Female; Humans; Male; Methicillin Resistance; Nose; Perineum; Prevalence; Staphylococcal Infections; Staphylococcus aureus; Swine; Swine Diseases

Serologic and virologic prevalence of infection with different swine influenza virus (SIV) subtypes was investigated using swine sera, nasal swabs and lung samples that had been submitted for a diagnosis to the Minnesota Veterinary Diagnostic Laboratory. A total of 111,418 pig sera were tested for SIV antibody between 1998 and 2000, and 25,348 sera (22.8%) were found to be positive by the hemagglutination inhibition (HI) test. Of the positive samples, 16,807 (66.7%) and 8,541 (33.7%) had antibody to H1 and H3 subtypes, respectively. Between January 1998 and May of 2001, a total of 3,561 nasal swabs or lung samples were examined for the presence of SIV, and SIV was isolated from 1,124 samples (31.7%). Of these isolates, 869 (77.3%) and 255 (22.7%) were subtyped as H1 and H3, respectively, by the HI method. For further characterization, 120 SIV isolates each from 1998 to 2001 were randomly selected from a culture collection and their hemagglutinin (HA) and neuraminidase genes examined by reverse transcription-PCR and sequencing. Of the 480 isolates, 322 (67.1%), 22 (4.6%) and 129 (26.9%) were subtyped as H1N1, H1N2 and H3N2, respectively. The remaining 7 samples (1.5%) were found to contain both H1N1 and H3N2 viruses. The SIV H1N2 subtype was isolated from 1, 8, and 13 samples in 1999, 2000, and 2001, respectively. The 22 H1N2 isolates originated from 9 different states of the United States. Genetic screening of the HA genes of 12 selected H1N2 isolates showed that 8 of them had a close phylogenetic relationship with the Indiana isolate of H1N2 (A/Swine/Indiana/9K035/99), while 4 isolates were closely related to classical SIV H1N1.

Topics: Amino Acid Sequence; Animal Husbandry; Animals; Antibodies, Viral; Hemagglutination Inhibition Tests; Hemagglutinin Glycoproteins, Influenza Virus; Influenza A virus; Lung; Molecular Sequence Data; Nose; Orthomyxoviridae Infections; Phylogeny; Prevalence; Reverse Transcriptase Polymerase Chain Reaction; Sequence Alignment; Sequence Analysis, DNA; Swine Diseases; United States

Three oligonucleotide primers for semi-nested polymerase chain reaction (PCR) were designed according to already published sequences of porcine circovirus types 1 (PCV-1) and 2 (PCV-2) isolates. These primers were used to detect PCV-2 DNA. A positive amplification reaction was visualized from a DNA suspension containing as few as 10 copies of virus DNA. In total. 77 samples of inguinal lymph nodes and nasal swabs from pigs in the Czech Republic were used to detect the virus. Thirty-seven of them were positive for PCV-2 DNA. In order to confirm specificity of the PCR reaction, seven DNA fragments were sequenced. Czech PCV sequences were found to have a 92-97% homology with other known PCV-2 strains and only 80-83% homology with PCV-1 strains.

Topics: Animals; Circoviridae Infections; Circovirus; Czech Republic; DNA Primers; DNA, Viral; Female; Lymph Nodes; Male; Nose; Phylogeny; Polymerase Chain Reaction; Swine; Swine Diseases

The purpose of the study was to evaluate the clinical significance of Actinobacillus minor, Actinobacillus porcinus and Actinobacillus indolicus strains in gnotobiotic piglets. Twenty-two 6-h-old Caesarean-delivered and colostrum-deprived piglets were intranasally and orally inoculated with 2 x 10(6) colony-forming units of an A. minor (group 2; n = 9), A. indolicus (group 3; n = 5), or A. porcinus (group 4; n = 8) strain. Six other piglets were inoculated in the same way with phosphate-buffered saline solution and used as controls (group 1). All pigs were observed for clinical signs and rectal temperatures were taken until euthanasia 7 days after inoculation. At necropsy, conchae, tonsils, lungs, brains, liver, spleen and kidneys were macroscopically examined for lesions and samples were taken for bacteriology. None of the pigs developed fever. Mild ataxia was observed in one pig from group 3 for 2 days. Clinical signs were not observed in the other animals. In none of the animals were macroscopic lesions detected at necropsy. NAD-dependent Pasteurellaceae were not isolated from control animals (group 1). The A. minor, A. indolicus and A. porcinus strains were isolated from the tonsils of one, two and one pigs, respectively. Actinobacillus porcinus was isolated from the brains of the pig with central nervous symptoms and from the conchae of another pig. The inoculation strains were not demonstrated in the other samples. It was concluded that, using these inoculation routes and dose, the A. minor, A. indolicus and A. porcinus strains had low capacity to colonize the upper respiratory tract of gnotobiotic piglets and demonstrated low or no pathogenicity in such animals.

Topics: Actinobacillus; Actinobacillus Infections; Animals; Animals, Newborn; Germ-Free Life; Nose; Palatine Tonsil; Swine; Swine Diseases

A PCR assay for the detection of Actinobacillus pleuropneumoniae was developed based on the amplification of a dsbE-like gene. All of 157 field isolates of A. pleuropneumoniae reacted in the PCR by the amplification of a 342bp product. No reaction was observed with related bacterial species or other bacterial species isolated from pigs, except for A. lignieresii. The lower detection limit of the PCR was 10(2) CFU per PCR test tube and was not affected by the addition of 10(6) CFU Escherichia coli. The PCR was evaluated on mixed bacterial cultures from nasal and tonsillar swabs as well as suspensions of nasal conchae and tonsils obtained from specific pathogen-free (SPF) pigs, experimentally infected pigs, and pigs from farrow-to-finish herds. The results of the new PCR were compared with a PCR based on the detection of the omlA gene coding for an outer membrane protein, with a commercially available PCR (Adiavet APP, Adiagène, Saint-Brieuc, France), and with conventional culturing. No positive reactions were observed with any of the PCR methods in samples of SPF animals. In samples of the other animals, no or low significant differences between nasal swabs and suspensions as well as tonsillar swabs and suspensions were observed in any method. In general, more positive results were obtained from tonsillar samples in comparison to nasal samples. Interassay sensitivity and specificity values were assessed for each test by pair wise comparisons between assays. The agreement between tests was evaluated by calculating Cohen's kappa coefficient. From these analyses the three PCR assays showed a good agreement. The dsbE-based PCR proved to be highly sensitive (95 and 93%) and specific (82 and 74%) in comparison to the omlA-based PCR and the commercially available PCR, respectively. It was concluded that the dsbE-like gene-based PCR is a reliable diagnostic assay for demonstration of A. pleuropneumoniae. Furthermore, it was demonstrated that tonsillar swabs can be used for the detection of the pathogen in healthy carrier animals.

Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Amino Acid Sequence; Animals; Base Sequence; Colony Count, Microbial; Consensus Sequence; DNA, Bacterial; Gene Amplification; Molecular Sequence Data; Nose; Palatine Tonsil; Polymerase Chain Reaction; Sensitivity and Specificity; Specific Pathogen-Free Organisms; Swine; Swine Diseases

Pigs reared in intensive production systems are continuously exposed to ammonia released by the microbial degradation of their excrement. Exposure to this gas has been shown to increase the severity of the disease progressive atrophic rhinitis by facilitating colonization of the pig's upper respiratory tract by Pasteurella multocida. The etiological mechanism responsible for this synergy was investigated by studying the colonization kinetics of P. multocida enhanced by ammonia and comparing them with those evoked by an established disease model. Three-week-old Large White piglets were weaned and allocated to five experimental groups (groups A to E). Pigs in groups A and B were exposed continuously to ammonia at 20 ppm for the first 2 weeks of the study. Pigs in group C were pretreated with 0.5 ml of 1% acetic acid per nostril on days -2 and -1 of the study. On day 0 all the pigs in groups A, C, and D were inoculated with 1.4 x 10(8) toxigenic P. multocida organisms given by the intranasal route. The kinetics of P. multocida colonization were established by testing samples obtained at weekly intervals throughout the study. The study was terminated on day 37, and the extent of turbinate atrophy was determined by using a morphometric index. The results of the study showed that exposure to aerial ammonia for a limited period had a marked effect on the colonization of toxigenic P. multocida in the nasal cavities of pigs, which resulted in the almost total exclusion of commensal flora. In contrast, ammonia had only a limited effect on P. multocida colonization at the tonsil. The exacerbation of P. multocida colonization by ammonia was restricted to the period of ammonia exposure, and the number of P. multocida organisms colonizing the upper respiratory tract declined rapidly upon the cessation of exposure to ammonia. During the exposure period, the ammonia levels in mucus recovered from the nasal cavity and tonsil were found to be 7- and 3.5-fold higher, respectively, than the levels in samples taken from unexposed controls. Acetic acid pretreatment also induced marked colonization of the nasal cavity which, in contrast to that induced by ammonia, persisted throughout the time course of the study. Furthermore, acetic acid pretreatment induced marked but transient colonization of the tonsil. These findings suggest that the synergistic effect of ammonia acts through an etiological mechanism different from that evoked by acetic acid pretreatment. A strong correlat

Topics: Acetic Acid; Administration, Inhalation; Ammonia; Animals; Colony Count, Microbial; Hydrogen-Ion Concentration; Mucus; Nasal Mucosa; Nose; Nose Diseases; Pasteurella Infections; Pasteurella multocida; Rhinitis, Atrophic; Swine; Swine Diseases

Serotyping of Actinobacillus pleuropneumoniae is based on detection of the serotype-specific capsular antigen. However, not all isolates can be serotyped, and some may cross-react with multiple serotyping reagents. To improve sensitivity and specificity of serotyping and for early detection, a multiplex PCR assay was developed for detection of A. pleuropneumoniae and identification of serotype 5 isolates. DNA sequences specific to the conserved export and serotype-specific biosynthesis regions of the capsular polysaccharide of A. pleuropneumoniae serotype 5 were used as primers to amplify 0.7- and 1.1-kb DNA fragments, respectively. The 0.7-kb fragment was amplified from all strains of A. pleuropneumoniae tested with the exception of serotype 4. The 0.7-kb fragment was not amplified from any heterologous species that are also common pathogens or commensals of swine. In contrast, the 1.1-kb fragment was amplified from all serotype 5 strains only. The assay was capable of amplifying DNA from less than 10(2) CFU. The A. pleuropneumoniae serotype 5 capsular DNA products were readily amplified from lung tissues obtained from infected swine, although the 1.1-kb product was not amplified from some tissues stored frozen for 6 years. The multiplex PCR assay enabled us to detect A. pleuropneumoniae rapidly and to distinguish serotype 5 strains from other serotypes. The use of primers specific to the biosynthesis regions of other A. pleuropneumoniae serotypes would expand the diagnostic and epidemiologic capabilities of this assay.

Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Animals; Bacterial Capsules; Bacterial Typing Techniques; Blotting, Southern; DNA Primers; DNA, Bacterial; Electrophoresis, Agar Gel; Lung; Nose; Pleuropneumonia; Polymerase Chain Reaction; Sensitivity and Specificity; Serotyping; Species Specificity; Swine; Swine Diseases

To establish the effect of dose on persistence of and immune response to Salmonella choleraesuis in swine.. 19 Salmonella-free pigs were allotted to 4 groups. Groups 1 (n = 5), 2 (n = 5), and 3 (n = 5) were inoculated intranasally with 10(9), 10(6), and 10(3) colony-forming units of S choleraesuis, respectively. Group 4 (n = 4) served as uninoculated controls.. Pigs were monitored for clinical signs of disease and bacterial shedding. Serum and lymphocytes were obtained to measure immune responses. Pigs from groups 1, 2, and 4 were necropsied at postinoculation (PI) weeks 6 and 15. Pigs from groups 3 and 4 were necropsied at PI weeks 6 and 10.. Pigs in group 1 shed S choleraesuis through PI week 15 and were tissue positive at PI weeks 6 and 15. Pigs in group 2 were tissue positive for S choleraesuis until PI week 6 and continued shedding through PI week 9. Salmonella choleraesuis was not recovered at any time from pigs in groups 3 or 4. Pigs in groups 1, 2, and 3 had serum IgG and IgM titers to S choleraesuis lipopolysaccharide and soluble antigens. Pigs in all groups had a lymphocyte response to concanavalin A, and pigs in groups 1 and 2 had a lymphocyte response to S choleraesuis endotoxin. Pigs in group 1 had a lower stimulation index in response to both antigens, indicating some form of lymphocyte immunosuppression.. Persistence of S choleraesuis in host tissues is dose dependent. Short-term persistence can occur after a dose as low as 10(6) colony-forming units of S choleraesuis. Higher doses result in development of long-term carrier status, which may be related to the observed lymphocyte immunosuppression.

Topics: Animals; Antibody Formation; Blood Sedimentation; Immunoglobulin G; Immunoglobulin M; Lymphocyte Activation; Lymphocytes; Nose; Palatine Tonsil; Rectum; Salmonella; Salmonella Infections, Animal; Swine; Swine Diseases

The continuous, non-invasive real-time monitoring of arterial oxygenation (pulse oximetry) has become a standard of care in both human and veterinary medicine. It allows reliable, simple and inexpensive assessment of the arterial oxygenation status. In pigs, commonly used sites for oximetry-probe placement are the ear, snout or tongue, while more recently the 'pig-tail oximetry' has been suggested. In a study regarding the coagulation system during amniotic fluid embolism (AFE) in mini-pigs, we compared tail and snout for oximetry-probe placement and compared them with the 'gold standard': blood-gas analysis (BGA). In both the AFE group and the control group, the tail measurements were slightly lower and the snout measurements were slightly higher than the BGA results. In the experimental model used, both tail and snout measurements were able to detect a temporary desaturation immediately after amniotic fluid embolism (AFE). Blood-gas analysis (BGA) performed on blood drawn from a large artery missed the event. Clinically, there is no significant difference between snout and tail as oximetry-probe placement sites: both are reliable oximetry sites in mini-pigs.

Topics: Animals; Blood Gas Analysis; Embolism, Amniotic Fluid; Female; Models, Biological; Nose; Oximetry; Pregnancy; Sulfur Oxides; Swine; Swine Diseases; Swine, Miniature; Tail

Nasal swabs and lungs of 150 pigs with pneumonia were tested by culture at post mortem examination. The isolated agents were Pasteurella multocida (P.m.), P. haemolytica, Bordetella bronchiseptica, Actinobacillus pleuropneumoniae, Staphylococcus aureus, Streptococcus spp. and Escherichia coli. P.m. was most frequently found, and this agent only showed a significant correlation between lungs and nasal swabs. In 80.6% of pigs with P.m. in the lung the agent was detected in the nose, too. Drug resistance patterns of P.m. isolates from lungs and noses of the single animals were identical or similar, also in case of different capsular types. The examination of porcine nasal swabs for bacteria capable of causing pneumonia should be limited to P. multocida. Demonstration of agents in lung material is generally more certain.

Topics: Animals; Anti-Bacterial Agents; Bacteria; Drug Resistance, Microbial; Lung; Nose; Pneumonia, Bacterial; Swine; Swine Diseases

A challenge-exposure model was developed for dose-dependent induction of subclinical (moderate) atrophic rhinitis (AR) in conventionally raised Dutch Landrace and Large White pigs, about 4 weeks old. Under favorable climatic and housing conditions, pigs were intranasally challenge-exposed with Pasteurella multocida-derived toxin (Pm-T) 3 days after pretreatment by inoculation with 1% acetic acid. Pigs were challenge-exposed with 1 of the following Pm-T doses: 0 (control), 5, 13, 20, or 40 micrograms of Pm-T/ml of phosphate-buffered saline solution (PBSS), 0.5 ml/nostril/d on 3 consecutive days. Five weeks after challenge exposure, subclinical (moderate) AR status was defined as intermediate conchal atrophy (grade 2 for ventral conchae on a 0 to 4 scale and grade 1 or 2 for dorsal conchae on a 0 to 3 scale, respectively) and perceptible difference in change in brachygnathia superior (cBS) between control and challenge-exposed pigs between the beginning and end of the study. All Pm-T-exposed pigs had nasal damage that was dose-dependent. The higher Pm-T doses resulted in higher ventral conchae atrophy and dorsal conchae atrophy scores. The cBS increased with applied Pm-T dose, resulting in significant (P < 0.05) differences between controls (3.88 mm) and the 13-, 20-, and 40-micrograms Pm-T-treated groups (7.77, 6.58, and 7.98 mm, respectively). In response to the applied dose, weight gain per week for Pm-T-exposed pigs was lower than that of controls after week 3 (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Administration, Intranasal; Animals; Atrophy; Bacterial Proteins; Bacterial Toxins; Nose; Pasteurella Infections; Pasteurella multocida; Rhinitis, Atrophic; Swine; Swine Diseases

Hysterectomy-produced colostrum-deprived 5- and 27-day-old pigs were inoculated intramuscularly (IM) or intranasally (IN) with the temperature-sensitive and thymidine kinase-deficient ZHtsTK- strain of Aujeszky's disease virus (ADV), and the nasal swabs and organs of the pigs were periodically collected for virus isolation. No abnormal clinical signs were observed in these pigs, except for a mild febrile response. Viral shedding in the nasal swabs with low titers was detected in the pigs inoculated IN between postinoculation day (PID) 1 and 5, but not in those of the pigs inoculated IM. No contact infection, however, occurred in the cohabiting pigs. Viruses with low titers were isolated only from the muscles and lymph nodes at the site of inoculation in the pigs inoculated IM on PID 2 and 4, but not from any organs of the pigs inoculated IN. To investigate the ability of the ZHtsTK- strain to establish a latent infection in pigs, the pigs inoculated IM or IN with the ZHtsTK- strain were treated with prednisolone. No virus was detected in the trigeminal ganglia or the nasal swabs collected after prednisolone treatment by the cocultivation method. The immunological evaluation demonstrated that immunization of pigs with this strain was effective in preventing clinical signs caused by ADV infection. The duration of virus shedding was markedly shortened in immunized pigs, particularly in those immunized twice and the total quantity of virus recovered from immunized pigs was reduced in comparison with unimmunized pigs.

Topics: Animals; Herpesvirus 1, Suid; Lymphocytes; Nose; Pseudorabies; Swine; Swine Diseases; Temperature; Thymidine Kinase; Vaccines, Attenuated; Viral Vaccines; Virus Replication

A commercial swine herd was selected for study, because pigs at slaughter repeatedly had lung lesions consistent with enzootic pneumonia and had snout lesions typical of atrophic rhinitis. Pigs born during various seasons of the year were allotted to 4 investigations and were evaluated from birth to slaughter. Individual lungs and snouts were identified and collected at the slaughter plant and later examined for gross lesions of bronchopneumonia and atrophic rhinitis, respectively. Each lesion was scored, and the following comparisons were made within investigations: prevalence and mean scores for lung lesions; prevalence and mean grades for snout lesions; correlations between lung lesion scores and growth indicators; correlations between snout lesion grades and growth indicators; and correlations between lung lesion scores and snout grade scores. Included in the growth indicators were average daily gain during the growing phase, average daily gain during the finishing phase, average daily gain during growing and finishing phases, and days to attain 104.5 kg of body weight. Prevalence of lung or snout lesions, mean values for lung lesion scores, mean values for snout lesion grades, and mean values for the various growth indicators were tested for statistical differences among the 4 investigations. Prevalence of lung lesions was highest (96%) for winter-slaughtered and lowest (81%) for autumn-slaughtered pigs. Mean scores for lung lesions were 7% (summer), 5% (autumn), 9% (winter), and 16% (spring). Prevalence of snout lesions was highest (85%) for spring-slaughtered pigs and lowest (42%) for autumn-slaughtered pigs.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Abattoirs; Animals; Bronchopneumonia; Lung; Nose; Prevalence; Rhinitis, Atrophic; Seasons; Swine; Swine Diseases; Weight Gain

Topics: Aflatoxins; Animal Feed; Animals; Drug Interactions; Glycine max; Lip; Male; Mouth; Necrosis; Nose; Oryza; Penis; Skin Ulcer; Swine; Swine Diseases; T-2 Toxin; Zea mays

Computerised tomography, used as a diagnostic tool for atrophic rhinitis in pigs, facilitated the macroscopic grading of the nasal structures in live pigs of any age. The results of sequential scans in normal and affected pigs are described; transient atrophy of the ventral conchae was observed in one pig.

Topics: Animals; Nose; Rhinitis, Atrophic; Swine; Swine Diseases; Tomography, X-Ray Computed

Topics: Animals; Bordetella; Bordetella Infections; Germ-Free Life; Nose; Pasteurella; Pasteurella Infections; Rhinitis, Atrophic; Swine; Swine Diseases

Nasal fluid and serum collected from pigs after exposure to live foot and mouth disease (FMD) virus or injection of single oil emulsion (w/o) or double oil emulsion (w/o/w) vaccines were examined for FMD neutralizing activity. After virus exposure the response profiles of serum and nasal mucus were similar to one another. In both, neutralizing activity rose to a peak at one to two weeks after exposure and then subsided slowly. After vaccination with either the w/o or w/o/w preparations a neutralizing response was demonstrable in the serum three to seven days after the first injection, and this was boosted by revaccinations 56 and 117 days later. The neutralizing activity was also detectable in nasal fluid seven days after the first vaccination, but subsequent revaccinations 56 and 117 days later provoked neutralizing titres which were no greater than those observed after the initial vaccination.

Topics: Animals; Antibodies, Viral; Aphthovirus; Foot-and-Mouth Disease; Neutralization Tests; Nose; Swine; Swine Diseases; Vaccination; Viral Vaccines

During pregnancy seven minimum-disease sows (group A) were infected intranasally with Bordetella bronchiseptica, fed with the killed bacterium periodically and inoculated parenterally with a dead vaccine eight, six and two weeks before parturition. Groups B and C, isolated from A until farrowing, contained respectively six sows given the vaccine parenterally and eight control sows. At parturition, group A had much higher average agglutinin titres in the serum and colostrum than B or C. Group A sows gave their piglets a better passive protection against infection with B bronchiseptica strain 293 and its effects in the respiratory tract during the first eight weeks of life, especially in those exposed to spontaneous infection with bordetellae from a littermate deliberately inoculated intranasally 24 hours after birth. Passive antibody strongly affected the capacity of piglets to respond actively to parenteral vaccination (when seven and 28 days old), marked humoral responses being noted only in those from group C sows. Vaccination of piglets exposed to infection by contact reduced neither the prevalence or intensity of the nasal infection, the amount of turbinate atrophy or pneumonia nor significantly improved weight gain compared with unvaccinated littermates. Unlike their eight-week-old littermates there was little hypoplasia and no pneumonia in infected pigs (whether vaccinated or not) when they reached five months of age.

Topics: Agglutination Tests; Animals; Bordetella; Bordetella Infections; Female; Immunity, Maternally-Acquired; Immunization; Nose; Pneumonia; Pregnancy; Swine; Swine Diseases

With the use of 16 gnotobiotic piglets inoculated at day 4, 5 and 6 of life with defference concentrations (3.10(4) to 3.10(9) colony forming units of Bordetella bronchiseptica per mL), it was possible to establish a minimal infective dose (3.10(5) CFU/mL). With a lower dose, it was not possible to induce any of the typical gross lesions of atrophic rhinitis. The authors discuss some factors which can modify the infection pressure in the field.

Topics: Agglutination Tests; Animals; Antibodies, Bacterial; Bordetella; Bordetella Infections; Germ-Free Life; Nasal Bone; Nasal Mucosa; Nose; Rhinitis, Atrophic; Swine; Swine Diseases

Bordetella bronchiseptica was eliminated from the nasal cavity of experimentally infected piglets after about three weeks by trimethoprim and sulphadiazine (potentiated sulphonamide) in the drinking water in two experiments (at levels of 13.3 and 66.7 micrograms per ml, respectively). The rhinitis and turbinate damage associated with the infection was significantly less when the animals were examined at seven weeks of age but daily weight gain was not improved to a significant extent compared with controls. Smaller quantities of potentiated sulphonamide were less active but no amount induced resistance in the bordetellae during the one month period of treatment.

Topics: Administration, Oral; Animals; Bordetella; Bordetella Infections; Nose; Sulfadiazine; Swine; Swine Diseases; Trimethoprim; Water

Clinical atrophic rhinitis in seven pig herds could not be associated with the infection rate or higher numbers of B bronchiseptica in nasal swabs when compared with unaffected herds. B bronchiseptica isolates from herds with atrophic rhinitis and receiving sulphonamide medication were resistant to sulphonamides in vitro and there was a beneficial clinical response after changing to oxytetracycline medication. In an unaffected herd three piglets naturally infected with B bronchiseptica but possessing low levels of passive antibody showed marked turbinate hypoplasia when killed at seven weeks, the lesions had resolved in four of six litter mates by 21 weeks and did not occur in another litter of nine piglets which had a high level of passive antibody. The results indicate that although B bronchiseptica can produce non-progressive turbinate changes in pigs that have inadequate antibody protection, the relationship between these lesions and the chronic progressive field disease needs further investigation.

Topics: Animals; Bordetella; Bordetella Infections; Chloramphenicol; Nose; Rhinitis, Atrophic; Swine; Swine Diseases; Tetracyclines

The piglets of two multiplier herds (M and B) showing clinically apparent atrophic rhinitis (AR) were treated by the nasal-spray method. A solution of oxytetracycline hydrochloride (OTC, 50 mg/ml.) was used as a spray fluid. The course of the disease in the herds was followed by studying the development of foreshortening of the upper jaws in the heads. Brachygnathia superior (BS), from the eighth to tenth week of life. Efforts were made to gain an impression of the effects of treatment on the frequency with which Bordetella bronchiseptica and Pasteurella multocida were isolated by bacteriological examination of the nose. Treatment by the nasal-spray method up to an age of approximately five weeks, of seven weeks were treated at least once weekly. The proportion of animals in which the disease was clinically apparent decreased from 25 per cent to 0 per cent in herd M and from 41 per cent to 0 per cent in herd B. Treatment by the nasal-spray method up to an age approximately five weeks, in which feed medicated with OTC was also given up to the age of eight to ten weeks also had a satisfactory effect. The frequency with which Bordetella bronchiseptica and Pasteurella multocida were isolated, was reduced by treatment, elimination of these agents was not.

Topics: Administration, Intranasal; Animals; Bordetella; Nose; Oxytetracycline; Pasteurella; Rhinitis, Atrophic; Swine; Swine Diseases

Eighteen seronegative swine weighing from 9 to 11 kg were exposed intranasally with the Shope strain of pseudorabies virus (PRV) and were observed for 21 days in an experiment to detect virus shedding and immune responses. All swine had PRV in their nasal passages at 7 days after exposure; they also had precipitating antibodies to PRV as determined by the microimmunodiffusion test (MIDT) and very low levels of virus-neutralizing (VN) antibodies. The PRV was isolated from only 2 swine at postexposure day 14; all swine were MIDT positive, and VN titers ranged from 4 to 128. Virus was not isolated from the swine at 21 days after exposure, but all were MIDT positive; VN titers ranged between 8 and greater than or equal to 256.

Topics: Animals; Antibody Formation; Herpesviridae; Herpesvirus 1, Suid; Neutralization Tests; Nose; Pseudorabies; Swine; Swine Diseases

Porcine infectious atrophic rhinitis is a disease of swine which ought to be of considerable interest to rhinologists. We have reviewed some aspects of human atrophic rhinitis, and some aspects of etiology incidence, pathology and physiology of porcine infectious atrophic rhinitis. Swine with this nasal problem fail rather dramatically, to gain as much weight as unaffected animals. We have speculated on several reasons for this including altered nasal physiology and trigeminal reflexes and reduced olfaction. Photographs of infected pigs are included.

Topics: Animals; Disease Models, Animal; Humans; Nasal Mucosa; Nose; Rhinitis, Atrophic; Swine; Swine Diseases

Control of infectious atrophic rhinitis in swine breeding herds by culturing of 3 series of nasal swab specimens from each animal, with subsequent elimination of Bordetella bronchiseptica culture-positive animals, was evaluated. Thirteen of 17 (77%) B bronchiseptica-infected herds experiencing clinical atrophic rhinitis were feedic rhinitis were freed of clinical signs of the disease by the use of this nasal culturing procedure. In 15 of 23 (65%) B bronchiseptica-infected herds, pigs were cultured negative for this organism at 4 to 10 weeks of age.

Topics: Animals; Bordetella; Bordetella Infections; Nose; Rhinitis, Atrophic; Swine; Swine Diseases

Septicemic disease occurred in 49 of 126 pigs several days after being transported 80 km. All affected pigs died. The main changes in acutely affected pigs were skin discoloration, pulmonary edema, arthritis, meningitis, and renal glomerular thrombosis. In peracute cases, gross findings were minimal. Haemophilus parasuis was isolated from multiple organ sites in most affected pigs. Haemophilus parasuis was isolated from nasal swab specimens from 17 of 20 clinically normal pigs on the farm of origin. Fatal acute septicemia was reproduced in 2 pigs by intravenous or intratracheal exposure to an isolant of H parasuis obtained from 1 of of the 49 fatally affected pigs. Aerosol exposure of 5 pigs resulted in mild pneumonia in 4 pigs and severe pneumonia, pleurisy, pericarditis, and terminal septicemia in 1 pig.

Topics: Animals; Brain; Haemophilus; Haemophilus Infections; Kidney; Lung; Nose; Swine; Swine Diseases; Synovial Fluid

A translocation with centric fusion between the Nos. 13 and 17 acrocentric chromosomes was described in a malformed female piglet and three phenotypically normal littermates by the G-banding staining technique. Since the translocation was heterozygous, the chromosome number was 37. The differences between the translocation of the present cases and those previously reported in the domestic swine species, as well as in some wild pigs, are mentioned.

Topics: Animals; Female; Heterozygote; Karyotyping; Male; Mouth Abnormalities; Nose; Sex Chromosome Aberrations; Swine; Swine Diseases; Translocation, Genetic

Ninety-five pigs, twelve suffering from atrophic rhinitis, were examined for the presence of protozoans in their nasal cavity. Tritrichomonas suis was isolated only in a single case in a diseased boar representing 1.09% of the set. Amoebae of the Vahlkampfia genus were detected in two pigs (2.1%). The axenic cultures of the two protozoans isolated from the pigs were not pathogenic to laboratory animals. No etiological relation of Tritochomonas suis to atrophic rhinitis was demonstrated.

Topics: Animals; Nasal Cavity; Nose; Protozoan Infections, Animal; Rhinitis, Atrophic; Swine; Swine Diseases; Tritrichomonas

The occurrence of Bordetella bronchiseptica and atrophic rhinitis was studied during a one-year period in four Danish sow herds. In three of the heards, the epidemiological studies revealed a relation between the occurrence of B. bronchiseptica in 3--10-week-old pigs and the presence and severity of atrophic rhinitis at slaughter. In the fourth herd no such relation was found.

Topics: Animals; Bordetella; Denmark; Female; Male; Nasal Cavity; Nose; Rhinitis, Atrophic; Swine; Swine Diseases

Snout radiography is a useful and practicable aid to the diagnosis of atrophic rhinitis. It is also a fairly reliable means of detecting and measuring turbinate atrophy and distortion of the septum nasi in the live pig. Suitable physical and pharmacological methods of restraining pigs for snout radiography are described and guide lines for producing satisfactory, standard snout radiographs are given. Parameters and criteria are recommended for qualitative and quantitative methods of interpreting snout radiographs. The quantitative scoring system approximates the macroscopic post mortem snout scoring system generally employed in Britain and provides data which might be used in genetic or other control programmes. Radiographic standards are tentatively suggested for certifying pigs free from gross lesions of atrophic rhinitis for sale or export purposes.

Topics: Anesthesia, General; Animals; Immobilization; Nose; Radiography; Swine; Swine Diseases; Technology, Radiologic; Turbinates

Snout rubbing led to ulceration and necrosis in pigs subjected to it. Only animals of specific colouring were attacked.

Topics: Animals; Behavior, Animal; Darkness; Female; Housing, Animal; Male; Muscles; Necrosis; Nose; Skin; Skin Pigmentation; Skin Ulcer; Swine; Swine Diseases

Antibody-mediated immune suppression occurred when newborn pigs with naturally acquired passive antibody were exposed to seine influenza virus. Frequency and relative ease of recovery of virus from nasal secretions were inversely related to the concentration of specific passive antibody existing at time of exposure. Severe overt respiratory signs during the acute stages of the disease were observed only in pigs with low passive antibody concentrations. The concentration of passive antibody at the time of exposure determined the immune status of the pig during the convalescent stage of disease. Infection could occur in the presence of high passive antibody concentrations, but the pig was not immunologically stimulated. Reexposure after the decay of passive antibody produced primary immune respone, severe clinical reinfection, and recovery of virus from nasal secretions for a period of time similar to that seen in pigs having their first exposure. Infection of newborn pigs with low passive antibody concentrations led to immunologic priming. A second exposure to virus produced a secondary immune response, mild clinical disease, and shortened time during which virus was recovered from nasal secretions. The relevance of these studies for the practice of vaccination or infections of the dam before parturition so that the neonate will have specific passive immunity is discussed.

Topics: Aerosols; Animals; Animals, Newborn; Antibody Formation; Antigen-Antibody Reactions; Antigens, Viral; Colostrum; Female; Hemagglutination Inhibition Tests; Immunization, Passive; Immunosuppression Therapy; Influenza Vaccines; Nose; Orthomyxoviridae; Orthomyxoviridae Infections; Specific Pathogen-Free Organisms; Swine; Swine Diseases; Vaccination

Topics: Animals; Germ-Free Life; Nose; Rhinitis, Atrophic; Specific Pathogen-Free Organisms; Swine; Swine Diseases

The K strain of Aujeszky's disease virus (ADV) grown in Vero cells was used to vaccinate pigs. Following intramuscular inoculation, the pigs remained healthy, no vaccine virus was excreted and virus could be detected only at the inoculation site. One inoculation gave good protection against challenge with a virulent strain of ADV, and the amount of virulent ADV excreted was geatly curtailed. Following vaccination only low leads of serum neutralizing antibody were detected (geometric mean titre 1/2), but three weeks after challenge very high levels were found (GMT 1/1773). Intranasal vaccination gave similar results. There was minimal excretion of vaccine virus. The clinical reaction on challenge was less severe than in the intramuscularly challenged group, although lower antibody levels were detected three wekks following challenge (GMT 1/483). A field trial, using this strain given subcutaneously, indicated that one inoculation of this vaccine is effective.

Topics: Administration, Intranasal; Animals; Cell Line; Chick Embryo; Haplorhini; Herpesviridae; Herpesvirus 1, Suid; Immunization; Injections, Intramuscular; Kidney; Neutralization Tests; Nose; Pseudorabies; Swine; Swine Diseases; Viral Vaccines

Five Iowa swine herds (involving about 7,000 swine) were placed under surveillance for signs of influenza-like illness. Blood samples for hemagglutination-inhibition (HI) tests of serums and nasal secretions on swabs for viral isolation were collected from 20 feeder swine in each herd at the outset of surveillance. On the basis of results of HI tests, 6 swine in each herd tested were chosen to be resampled 6 weeks after the first blood sample was collected if swine influenza virus (SIV) was not isolated, but 3 weeks after the first blood sample was collected if SIV was isolated at the outset of surveillance. The swine chosen for resampling were considered sentinels in a herd for the duration of surveillance. Swine influenza virus was isolated from 20 of 20 swine in each of 2 herds that had signs of influenza-like illness. The initial HI titer of each of the 20 swine in the 2 herds was less than 10. However, serum samples prepared from blood collected from sentinel swine in the 2 herds 3 weeks after isolation of SIV had HI geometric mean titers (GMT) of 23 and 34. One herd had an initial HI GMT of 21. A SIV was not isolated from this herd, and serum samples obtained from 3 of the 6 sentinel seine 6 weeks after the first blood sample was collected still had demonstrable HI antibody.

Topics: Animals; Chick Embryo; Iowa; Nose; Orthomyxoviridae; Orthomyxoviridae Infections; Swine; Swine Diseases

The air of loose-boxes holding pigs affected with swine vesicular disease was sampled for virus. In the multistage impinger virus to a titre of 10(2.6) TCID 50 was associated with particles greater than 6 mum., 10(1.6) with particles 3-6 mum. and 10(1.4) or less with particles less than 3 mum. In the noses of workers in contact with the pigs for periods not less than 5 min., virus to a titre of 10(2.4) TCID 50 was found. Virus was recovered from the air for 2-3 days during the disease and maximum titre in pigs infected by injection or by contact occurred on the second to third day after generalization of the lesions. The amounts of virus were about 160-fold less than those recovered from pigs affected with foot-and-mouth disease, and the quantity and time of excretion suggest that the source of swine vesicular disease virus in the aerosol may be from the lesions and skin rather than from the respiratory tract.

Topics: Air Microbiology; Animals; Enterovirus; Enterovirus Infections; Foot; Housing, Animal; Humans; Lip; Nose; Skin; Swine; Swine Diseases

Topics: Acetates; Administration, Oral; Animal Feed; Animals; Bone Diseases; Calcium, Dietary; Diet; Glycine max; Nose; Phosphorus; Rhinitis; Swine; Swine Diseases; Turbinates; Zea mays

Topics: Abnormalities, Multiple; Animals; Eye Abnormalities; Maxilla; Nose; Swine; Swine Diseases

Topics: Age Factors; Animals; Animals, Newborn; Arthritis; Bacterial Infections; Body Weight; Culture Media; Denmark; Female; Jejunum; Moraxella; Nose; Parity; Pneumonia; Pregnancy; Seasons; Spleen; Swine; Swine Diseases

Topics: Abscess; Administration, Intranasal; Administration, Oral; Animals; Culture Media; Fluorescent Antibody Technique; Lymphadenitis; Nose; Palatine Tonsil; Streptococcal Infections; Streptococcus; Swine; Swine Diseases; Time Factors

Topics: Abscess; Animal Feed; Animals; Carrier State; Germ-Free Life; Lymphadenitis; Nose; Palatine Tonsil; Soil Microbiology; Streptococcal Infections; Streptococcus; Swine; Swine Diseases

Topics: Animals; Germ-Free Life; Lung; Mycoplasma; Mycoplasma Infections; Nose; Pasteurella; Pasteurella Infections; Respiratory System; Swine; Swine Diseases; Trachea

Topics: Animals; Antibodies, Bacterial; Bordetella; Female; Maternal-Fetal Exchange; Nose; Pregnancy; Rhinitis, Atrophic; Swine; Swine Diseases; Vaccination

Topics: Age Factors; Animals; Antibodies, Viral; Carrier State; Nose; Palatine Tonsil; Pseudorabies; Swine; Swine Diseases

Topics: Animals; Antibodies; Brain; Cattle; Female; Herpesviridae Infections; Herpesvirus 1, Bovine; Injections; Injections, Intravenous; Male; Neutralization Tests; Nose; Swine; Swine Diseases

Topics: Adenoviridae Infections; Administration, Oral; Animals; Brain; Germ-Free Life; Meningoencephalitis; Nose; Swine; Swine Diseases

Topics: Animals; Brain; Cell Nucleus; Inclusion Bodies; Japan; Lung; Nose; Rhinitis; Skin; Spleen; Swine; Swine Diseases

Topics: Animals; Antibodies, Bacterial; Antigens, Bacterial; Bacterial Vaccines; Blood; Bordetella; Bordetella Infections; Bordetella pertussis; Culture Media; Injections, Subcutaneous; Nasal Mucosa; Nose; Pertussis Vaccine; Swine; Swine Diseases; Vibration; Virulence

Topics: Administration, Oral; Animals; Animals, Newborn; Brain; Encephalomyelitis; Feeding and Eating Disorders; Female; Fluorescent Antibody Technique; Hemagglutination, Viral; Humans; Infant, Newborn; Lung; Microscopy, Fluorescence; Nasal Mucosa; Nose; Orthomyxoviridae; Paramyxoviridae; Pregnancy; Pulmonary Fibrosis; Respiratory Distress Syndrome, Newborn; Swine; Swine Diseases; Trachea; Vomiting

Topics: Animals; Bordetella; Bordetella Infections; Gentamicins; Nose; Rhinitis, Atrophic; Swine; Swine Diseases

Topics: Animals; Colostrum; Culture Media; Germ-Free Life; Housing, Animal; Hysterectomy; Lung; Mycoplasma; Mycoplasma Infections; Nasal Mucosa; Nose; Pneumonia; Swine; Swine Diseases; Virus Cultivation

Topics: Animals; Anti-Bacterial Agents; Housing, Animal; Immunity, Active; Lung; Mycoplasma; Mycoplasma Infections; Nasal Mucosa; Nose; Pneumonia; Swine; Swine Diseases

Topics: Animals; Antibody Formation; Feces; Hemagglutination Inhibition Tests; Humans; Nose; Reoviridae; Reoviridae Infections; Swine; Swine Diseases

Topics: Animals; Aphthovirus; Carrier State; Cattle; Cattle Diseases; Foot-and-Mouth Disease; Humans; Nose; Swine; Swine Diseases

Topics: Animals; Fluorescent Antibody Technique; Germ-Free Life; Injections; Kidney; Liver; Lung; Mycoplasma; Nose; Pneumonia; Rabbits; Spleen; Swine; Swine Diseases

Topics: Agglutination Tests; Alcaligenes; Animals; Bacterial Infections; Nasal Mucosa; Nose; Rhinitis, Atrophic; Swine; Swine Diseases; Turbinates

Topics: Ammonia; Animals; Conjunctivitis; Dust; Epithelium; Germ-Free Life; Housing, Animal; Nose; Swine; Swine Diseases; Time Factors; Trachea; Turbinates; Zea mays

Topics: Animals; Epithelium; Germ-Free Life; Nose; Respiratory System; Respiratory Tract Diseases; Sulfur Dioxide; Swine; Swine Diseases; Trachea; Turbinates

Topics: Agglutination Tests; Animals; Bordetella; Bordetella Infections; Colostrum; Germ-Free Life; Hysterectomy; Nose; Rhinitis, Atrophic; Swine; Swine Diseases

Hysterectomy-produced, colostrum-deprived (HPCD) pigs and naturally born, enzootic-pneumonia-free (EPF) pigs were compared with respect to their susceptibility to two strains of enzootic pneumonia induced by intranasal inoculation of suspensions of ground pneumonic tissue. All but one of the HPCD pigs developed enzootic pneumonia, whereas the EPF pigs commonly failed to develop the disease; secondly, the pneumonic lesions were more extensive in the HPCD pigs.When the dose of inoculum was increased in EPF pigs, the resulting pneumonic areas were larger.In a small, in-contact experiment the disease was also more readily transmitted to HPCD pigs than to EPF pigs.

Topics: Animals; Colostrum; Germ-Free Life; Hysterectomy; Injections; Mycoplasma; Mycoplasma Infections; Nose; Pneumonia; Swine; Swine Diseases

Topics: Animals; Body Temperature; Feces; Hematocrit; Leukocyte Count; Leukocytosis; Lymphadenitis; Nose; Peritonsillar Abscess; Streptococcal Infections; Streptococcus; Swine; Swine Diseases; Time Factors

Topics: Animals; Haemophilus; Haemophilus Infections; Lung; Nose; Pneumonia; Swine; Swine Diseases; Trachea

Topics: Animals; Cattle; Cell Line; Complement Fixation Tests; Cytopathogenic Effect, Viral; Feces; Germ-Free Life; Haplorhini; Hemagglutination Inhibition Tests; Horses; Humans; Kidney; Microscopy, Electron; Neutralization Tests; Nose; Reoviridae; Reoviridae Infections; Swine; Swine Diseases; Thyroid Gland; Virus Cultivation

Sampling of human subjects, who had been in contact with animals infected with foot-and-mouth disease (FMD) virus, showed that virus could be recovered from the nose, throat, saliva and from air expelled during coughing, sneezing, talking and breathing. The amounts of virus recovered paralleled those collected with a large-volume sampler and multistage impinger and these findings confirmed that the highest recovery of airborne virus was from infected pigs followed by cattle and sheep. More virus was found in the noses of those examining infected animals than in those operating the samplers, but there was variation between the subjects. In the majority there was a 1.8 log fall in titre by 3.5 hr., but virus persisted in the nose of one subject for 28 hr. Nose blowing or washing the nostrils did not remove virus completely, nor were cloth or industrial masks completely effective in preventing inhalation of virus. It was possible to transmit virus from infected subjects to others on one occasion. No clinical cases of FMD in man resulted from exposure, nor was there any rise in antibody. Use was made of these findings in determining sites of aerosol excretion in animals, and the results are discussed in relation to FMD in man and to the spread of respiratory viruses by the airborne route.

Topics: Air Microbiology; Animals; Aphthovirus; Cattle; Cattle Diseases; Cough; Foot-and-Mouth Disease; Humans; Masks; Nose; Pharynx; Respiration; Saliva; Sheep; Sheep Diseases; Sneezing; Swine; Swine Diseases

Topics: Age Factors; Animals; Japan; Nose; Rhinitis, Atrophic; Swine; Swine Diseases

Topics: Abscess; Animals; Bacteriophage Typing; Corynebacterium; Germ-Free Life; Lymphadenitis; Mouth; Nose; Serotyping; Streptococcal Infections; Streptococcus; Swine; Swine Diseases

Topics: Animals; Anti-Bacterial Agents; Arthritis; Arthritis, Infectious; Exudates and Transudates; Lincomycin; Lymph Nodes; Mucous Membrane; Mycoplasma; Mycoplasma Infections; Nose; Pharynx; Swine; Swine Diseases; Synovial Fluid

Topics: Animals; Bordetella; Infection Control; Infections; Nose; Sulfonamides; Swine; Swine Diseases; Trachea

Topics: Animals; Bronchi; Germ-Free Life; Lung; Lymphocytes; Monocytes; Mycoplasma Infections; Neutrophils; Nose; Plasma Cells; Pneumonia; Pulmonary Alveoli; Reticulin; Swine; Swine Diseases

Topics: Animals; Bacteria; Infections; Iowa; Nose; Rhinitis, Atrophic; Swine; Swine Diseases

Topics: Animals; Cattle; Cattle Diseases; Colostrum; Female; Hemagglutination Inhibition Tests; Influenza, Human; Lung; Neutralization Tests; Nose; Orthomyxoviridae; Orthomyxoviridae Infections; Paramyxoviridae Infections; Pathology; Pregnancy; Research; Sheep; Sheep Diseases; Swine Diseases; Virus Cultivation

Topics: Animals; Atrophy; Autopsy; Endoscopy; Nose; Rhinitis; Rhinitis, Atrophic; Swine; Swine Diseases

Topics: Animals; Nose; Pasteurella Infections; Pasteurella multocida; Rhinitis; Rhinitis, Atrophic; Swine; Swine Diseases

Topics: Animals; Atrophy; Endoscopy; Nose; Rhinitis; Rhinitis, Atrophic; Swine; Swine Diseases

Topics: Animals; Atrophy; Endoscopy; Nose; Rhinitis; Rhinitis, Atrophic; Swine; Swine Diseases

Topics: Animals; Cattle; Fusobacterium Infections; Humans; Male; Nose; Rhinitis; Soft Tissue Infections; Swine; Swine Diseases