lactoferrin and Streptococcal-Infections

Adverse pregnancy outcomes affect 54 million people globally per year, with at least 50% of these attributed to infection during gestation. These include inflammation of the membranes surrounding the growing fetus (chorioamnionitis), preterm prelabor rupture of membranes (PPROM), preterm birth (PTB), early-onset disease (EOD) and late-onset disease (LOD), neonatal and maternal sepsis, and maternal or fetal demise. Although universal screening and implementation of intrapartum antibiotic prophylaxis (IAP) has improved EOD outcomes, these interventions have not reduced the incidences of LOD or complications occurring early on during pregnancy such as PPROM and PTB. Thus, novel therapies are needed to prevent adverse pregnancy outcomes and to ameliorate disease risk in vulnerable populations. Lactoferrin has recently been explored as a potential therapeutic as it demonstrates strong antimicrobial and anti-biofilm activity. Lactoferrin is a glycoprotein capable of iron chelation found in a variety of human tissues and is produced in high concentrations in human breast milk. In recent studies, lactoferrin has shown promise inhibiting growth and biofilm formation of streptococcal species, including Group B Streptococcus (GBS), a prominent perinatal pathogen. Understanding the interactions between lactoferrin and GBS could elucidate a novel treatment strategy for adverse pregnancy outcomes caused by GBS infection.

Topics: Female; Humans; Infant, Newborn; Lactoferrin; Pregnancy; Premature Birth; Risk Factors; Streptococcal Infections; Streptococcus agalactiae

Streptococcal species are Gram-positive bacteria responsible for a variety of disease outcomes including pneumonia, meningitis, endocarditis, erysipelas, necrotizing fasciitis, periodontitis, skin and soft tissue infections, chorioamnionitis, premature rupture of membranes, preterm birth, and neonatal sepsis. In response to streptococcal infections, the host innate immune system deploys a repertoire of antimicrobial and immune modulating molecules. One important molecule that is produced in response to streptococcal infections is lactoferrin. Lactoferrin has antimicrobial properties including the ability to bind iron with high affinity and sequester this important nutrient from an invading pathogen. Additionally, lactoferrin has the capacity to alter the host inflammatory response and contribute to disease outcome. This Review presents the most recent published work that studies the interaction between the host innate immune protein lactoferrin and the invading pathogen,

Topics: Anti-Infective Agents; Female; Humans; Immunity; Infant, Newborn; Lactoferrin; Pregnancy; Premature Birth; Streptococcal Infections

Neonatal sepsis remains a feared cause of morbidity and mortality in the neonatal period. Maternal, neonatal, and environmental factors are associated with risk of infection, and a combination of prevention strategies, judicious neonatal evaluation, and early initiation of therapy are required to prevent adverse outcomes. This article reviews recent trends in epidemiology and provides an update on risk factors, diagnostic methods, and management of neonatal sepsis.

Topics: Adaptive Immunity; Anti-Infective Agents; Antibodies, Monoclonal; Antifungal Agents; Bacterial Infections; Biomarkers; Blood Cell Count; C-Reactive Protein; Candidiasis; Escherichia coli Infections; Fluconazole; Genomics; Humans; Immunity, Innate; Immunoglobulins, Intravenous; Infant, Newborn; Infant, Newborn, Diseases; Lactoferrin; Polymerase Chain Reaction; Predictive Value of Tests; Proteomics; Risk Factors; Sepsis; Streptococcal Infections; Streptococcus agalactiae

Topics: Anti-Bacterial Agents; Biofilms; Female; Humans; Infant, Newborn; Lactoferrin; Milk, Human; Pregnancy; Streptococcal Infections; Streptococcus agalactiae

Streptococcus uberis is one of the most prevalent pathogens causing clinical and subclinical mastitis worldwide. Among bacterial factors involved in intramammary infections caused by this organism, S. uberis adhesion molecule (SUAM) is one of the main virulence factors identified. This molecule is involved in S. uberis internalization to mammary epithelial cells through lactoferrin (Lf) binding. The objective of this study was to evaluate SUAM properties as a potential subunit vaccine component for prevention of S. uberis mastitis. B epitope prediction analysis of SUAM sequence was used to identify potentially immunogenic regions. Since these regions were detected all along the gene, this criterion did not allow selecting a specific region as a potential immunogen. Hence, four fractions of SUAM (-1fr, 2fr, 3fr and 4fr), comprising most of the protein, were cloned and expressed. Every fraction elicited a humoral immune response in mice as predicted by bioinformatics analysis. SUAM-1fr generated antibodies with the highest recognition ability towards SUAM native protein. Moreover, antibodies against SUAM-1fr produced the highest proportion of internalization inhibition of S. uberis to mammary epithelial cells. In conclusion, SUAM immunogenic and functionally relevant regions were identified and allowed to propose SUAM-1fr as a potential candidate for a subunit vaccine for S. uberis mastitis prevention.

Topics: Amino Acid Sequence; Animals; Antibodies, Bacterial; Bacterial Adhesion; Bacterial Proteins; Bacterial Vaccines; Base Sequence; Cattle; DNA, Bacterial; Epithelial Cells; Female; Immunoglobulin G; Lactoferrin; Mastitis; Mice; Models, Animal; Recombinant Proteins; Streptococcal Infections; Streptococcus; Vaccines, Subunit; Virulence Factors

The objective of this study is to evaluate the importance of human lactoferrin (hLF) in an experimental caries induced by Streptococcus mutans in a lactoferrin-knockout (LFKO(-/-)) mouse model compared with C576J/BL wild-type (WT) mice.. The WT and LFKO(-/-) mice were infected with S. mutans (1 × 10(8) cells) and/or sham infection. Furthermore, the effect of hLF administration was evaluated in LFKO(-/-) mice infected with S. mutans. Mice were assessed for colonization, salivary pH, and caries development.. The results showed that the lactoferrin-knockout infected (LFKO(-/-) I) mice had significantly higher colonization with S. mutans (P = 0.02), lower salivary pH (P = 0.01), and more carious lesions (P = 0.01) when compared to wild-type infected (WTI) mice. In addition, the administration of hLF did not show any evidence of S. mutans colonization as well as carious lesions (P = 0.001) in LFKO(-/-) I mice when compared to untreated LFKO(-/-) I mice.. These results show that endogenous LF protects against S. mutans-induced caries and that exogenous hLF can exert a protective effect against caries development.

Topics: Animals; Anti-Infective Agents; Dental Caries; Humans; Hydrogen-Ion Concentration; Lactoferrin; Male; Mice; Mice, Knockout; Saliva; Streptococcal Infections; Streptococcus mutans

Streptococcus dysgalactiae ssp. dysgalactiae is an important causative agent of bovine mastitis worldwide. Lactoferrin is an innate immune protein that is associated with many functions including immunomodulatory, antiproliferative, and antimicrobial properties. This study aimed to investigate the interactions between lactoferrin and a clinical bovine mastitis isolate, Strep. dysgalactiae ssp. dysgalactiae DPC5345. Initially a deliberate in vivo bovine intramammary challenge was performed with Strep. dysgalactiae DPC5345. Results demonstrated a significant difference in lactoferrin mRNA levels in milk cells between the control and infused quarters 7h postinfusion. Milk lactoferrin levels in the Strep. dysgalactiae DPC5345 infused quarters were significantly increased compared with control quarters at 48h postinfusion. In vitro studies demonstrated that lactoferrin had a bacteriostatic effect on the growth of Strep. dysgalactiae DPC5345 and significantly decreased the ability of the bacteria to internalize into HC-11 mammary epithelial cells. Confocal microscopy images of HC-11 cells exposed to Strep. dysgalactiae and lactoferrin further supported this effect by demonstrating reduced invasion of bacteria to HC-11 cells. The combined data suggest that a bovine immune response to Strep. dysgalactiae infection includes a significant increase in lactoferrin expression in vivo, and based on in vitro data, lactoferrin limits mammary cell invasion of this pathogen by binding to the bacteria and preventing its adherence.

Topics: Animals; Anti-Bacterial Agents; Cattle; Cattle Diseases; Epithelial Cells; Female; Immunity, Innate; Lactoferrin; Mammary Glands, Animal; Mastitis, Bovine; Milk; RNA, Messenger; Streptococcal Infections; Streptococcus

Many outer multidomain proteins play fundamental virulent roles in an allele-dependent manner. We aimed to investigate the influence of the outer SP1992 protein, here renamed DiiA (Dimorphic invasion-involved A), in pneumococcal disease.. The presence and type of diiA allele was screened by PCR in 560 clinical isolates. Isogenic mutants carrying progressive diiA deletions were constructed and checked in mouse models of infection. DiiA binding to human molecules was carried out by surface plasmon resonance.. The diiA gene is exclusive of Streptococcus pneumoniae and included in the core genome. DiiA variants contain one or two imperfect repeats (R1 and R2), an unstructured region and a cell-wall anchor domain. Clonal complexes carrying both repeats were associated with invasive disease, while those carrying R2 preferentially caused non-invasive syndromes in patients with underlying risk factors. Mutants lacking both repeats were less efficient in nasopharyngeal colonization and dissemination from lungs. Moreover, the ΔdiiA defective strain suffered a severe impairment in bacterial proliferation in blood. Purified DiiA bound to collagen and lactoferrin with high affinity.. DiiA is a distinctive pneumococcal virulence factor contributing to colonization and long-term invasion in this pathogen.

Topics: Adult; Animals; Bacterial Proteins; Cell Wall; Collagen; Disease Models, Animal; Gene Deletion; Humans; Lactoferrin; Male; Mice, Inbred C57BL; Polymerase Chain Reaction; Protein Binding; Streptococcal Infections; Streptococcus pneumoniae; Surface Plasmon Resonance; Virulence Factors

Lactoferrin (LF) is one of the prebiotics present in the human body. A 38-year-old multiparous woman with poor obstetrical histories, three consecutive preterm premature rupture of membrane at the 19th, 23rd and 25th week of pregnancy, was referred to our hospital. She was diagnosed as having refractory vaginitis. Although estriol vaginal tablets were used for 4 months, the vaginitis was not cured. We administrated vaginal tablets and oral agents of prebiotic LF, resulting in a Lactobacillus predominant vaginal flora. When she was pregnant, she continued to use the LF, and the Lactobacillus in the vaginal flora was continuously observed during pregnancy. An elective cesarean section was performed at the 38th week of pregnancy. When the administration of LF was discontinued after the delivery, Lactobacillus in the vaginal flora was disappeared.

Topics: Adult; Female; Fetal Membranes, Premature Rupture; Humans; Lactobacillus; Lactoferrin; Prebiotics; Pregnancy; Pregnancy Complications, Infectious; Premature Birth; Streptococcal Infections; Streptococcus agalactiae; Vagina; Vaginosis, Bacterial

Streptococcus mutans is the primary agent of dental caries, which is often detected in transient bacteremia. Lactoferrin is a multifunctional glycoprotein showing antibacterial activities against several Streptococcus species. We reported here the prophylactic effect of human lactoferrin (hLF) in a lactoferrin knockout mouse (LFKO-/-) bacteremic model. The hLF treatment significantly cleared S. mutans from the blood and organs of bacteremic mice when compared to the non-hLF treated mice. Further, analysis of serum cytokines, spleen and liver cytokine mRNA levels revealed that hLF prophylaxis modulates their release differently when compared to the non-hLF treated group. C-reactive protein level (P = 0.003) also decreased following hLF prophylaxis in S. mutans induced bacteremic mice. Additional quantitative RT-PCR analysis revealed that hLF prophylaxis significantly decreased the expression level of IFN-γ, TNF-α, IL-1β, IL-6, MPO and iNOS in spleen and liver. These results suggested that the hLF protects the host against S. mutans-induced experimental bacteremia.

Topics: Animals; Anti-Bacterial Agents; Bacteremia; C-Reactive Protein; Granulocyte Colony-Stimulating Factor; Humans; Interferon-gamma; Interleukin-1beta; Interleukin-3; Interleukin-6; Lactoferrin; Liver; Male; Mice; Mice, Knockout; Nitric Oxide Synthase Type II; Recombinant Fusion Proteins; Spleen; Streptococcal Infections; Streptococcus mutans; Tumor Necrosis Factor-alpha

Streptococcus uberis is the most common environmental mastitis pathogen causing udder inflammations of different severities in dairy cows. The aim of the study was to investigate if the different clinical outcome of mastitis induced by different strains of S. uberis can be reflected in the mammary immune response. Mammary epithelial cells and somatic milk cells were treated with heat inactivated and living S. uberis of strain A and strain B in vitro. Strain A was repeatedly isolated from a chronically infected quarter during 8 months, and persisted in the quarter despite antibiotic treatment. Strain B caused an acute clinical mastitis and was not further isolated after a single antibiotic treatment. Treatment with Strain B induced a more pronounced increase of mRNA-expression of various immune factors (interleukin-8, interleukin-1beta, RANTES, and lactoferrin) in mammary epithelial cells than strain A. In contrast to mammary epithelial cells the response of removed somatic milk cells showed no differences between the stimulation with two S. uberis strains. Tumor necrosis factor-alpha mRNA expression was not differently induced by the two strains. In conclusion, the characteristics of different severities of mastitis that are induced by different S. uberis strains in vivo can also be reflected at the level of the immune response of the mammary gland in vitro.

Topics: Animals; Cattle; Cells, Cultured; Chemokine CCL5; Cytokines; Epithelial Cells; Female; Gene Expression Regulation, Bacterial; Interleukin-1beta; Interleukin-8; Lactoferrin; Mammary Glands, Animal; Mastitis, Bovine; Milk; RNA, Messenger; Severity of Illness Index; Streptococcal Infections; Streptococcus; Tumor Necrosis Factor-alpha

Bovine mastitis is one of the most deleterious diseases for dairy herds and is mainly caused by contagious and environmental bacterial pathogens. Among contagious bacteria, Staphylococcus aureus is the most prevalent, whereas the main environmental mastitis pathogens are Streptococcus uberis and Escherichia coli. Bovine lactoferrin (bLF) is an approximately 80-kDa glycoprotein present in milk that participates in the innate response of the mammary gland against bacterial infection. The objectives of the current study were to analyze potential changes in bLF milk concentration, which would constitute a response of the mammary gland toward mastitis induced by different etiologic agents, and to evaluate a possible relation between this response and pathogen susceptibility to bLF. Microbiology analysis and bLF quantification in milk from different bovine mammary gland quarters were performed. Infected quarters presented greater concentrations of bLF compared with those from microbiologically negative quarters. Analysis of individual pathogen contributions showed that most of this increase was attributable to Strep. uberis intra-mammary infection. The ability of mammary gland cells to synthesize bLF in response to Strep. uberis challenge was demonstrated by immunodetection of the protein in in vitro infection experiments. Susceptibility of Strep. uberis, E. coli, and Staph. aureus to the antimicrobial activity of bLF was determined by growth inhibition assays conducted with 4 different isolates of each species. Whereas Staph. aureus and E. coli were shown to be susceptible to this protein, Strep. uberis appeared to be resistant to the antimicrobial activity of bLF. Molecular typing of the 4 Strep. uberis isolates used throughout this study showed that this result was representative of the species and not exclusive of a particular strain. Results presented herein suggest that different bacteria species may elicit different mammary gland responses mediated by bLF secretion and that Strep. uberis has probably adapted to this immune reaction by developing resistance to bLF inhibitory action.

Topics: Animals; Cattle; Enzyme-Linked Immunosorbent Assay; Escherichia coli; Escherichia coli Infections; Female; Lactoferrin; Mammary Glands, Animal; Mastitis, Bovine; Milk; Species Specificity; Staphylococcal Infections; Staphylococcus aureus; Streptococcal Infections; Streptococcus

Oral and pharyngeal cavities harbor a commensal bacterial flora which is kept in check by several innate and acquired agents. In this study, we focused on the proportions in which some antibacterial moderators (lysozyme, lactoferrin, IgG and S-IgA) coat the tonsillar surface bacteria in healthy individuals, in patients with acute tonsillitis (AT) culture-positive for Streptococcus pyogenes, and in patients with infectious mononucleosis (IM) caused by Epstein-Barr virus (EBV).. Bacterial samples were collected for aerobic culturing and immunocytochemical evaluation from the tonsillar surfaces of eight healthy individuals (four males, four females; age range 16-22 years), eight patients with current AT (two males, six females; age range 16-29 years) and seven patients with IM (four males, three females; age range 15-21 years). The immunocytochemical assay was based on gold-labeled antiserum to human lysozyme, lactoferrin, IgG and S-IgA followed by gold particle tracing in the transmission electron microscope.. During AT, a significant increase in lysozyme coating (P<0.05) and lactoferrin coating (P<0.0005) of the bacteria was noted, whereas the S-IgA coating was significantly reduced (P<0.0005). During IM infection, a significant increase in lactoferrin coating was noted (P<0.0005) whereas immunoglobulin coating was significantly reduced (IgG P<0.025; S-IgA P<0.0005) compared with healthy controls. During IM, all antibacterial moderators evaluated were significantly reduced compared with the situation during AT.. Noticeable changes in the local innate and acquired bacterial defence system were observed during tonsillar infections, particularly during IM.

Topics: Acute Disease; Adolescent; Adult; Case-Control Studies; Female; Herpesvirus 4, Human; Humans; Immunity, Innate; Immunoglobulin A; Immunoglobulin G; Immunohistochemistry; Infectious Mononucleosis; Lactoferrin; Male; Muramidase; Palatine Tonsil; Streptococcal Infections; Streptococcus pyogenes; Tonsillitis

The therapeutic effect of administering lactoferrin hydrolysate (LFH) into the mammary glands of cows with subclinical mastitis was evaluated. Seven millilitres of a preparation of LFH (7% protein) was infused into 35 quarters of 25 cows with subclinical mastitis. The numbers of bacteria in the milk from infected quarters decreased, and bacteria disappeared by the 14th day after the administration of LFH. The mean somatic cell counts (SCC) peaked one day after administration of LFH and the counts were significantly p < 0.01) decreased on days 7, 14 and 21 compared to those before the administration of LFH. The mean lactoferrin concentration in the milk peaked on days 2 or 3 and then gradually decreased to day 14, returning to the level before the administration of LFH. It appears that administration of LFH may have a therapeutic effect when infused into the quarters of cows with subclinical mastitis.

Topics: Animals; Cattle; Cell Count; Escherichia coli Infections; Female; Lactoferrin; Mammary Glands, Animal; Mastitis, Bovine; Milk; Staphylococcal Infections; Streptococcal Infections

Three strains of Streptococcus dysgalactiae subsp. dysgalactiae (UT516, UT519, ATCC 27957) were used to determine if bovine lactoferrin (Lf) binds to bacterial cells by biotin avidin binding assay (BABA), enzyme-linked immunosorbent assay (ELISA), and binding inhibition assay. Binding assays revealed that all strains of S. dysgalactiae subsp. dysgalactiae (S. dysgalactiae) evaluated in this study bound to Lf. However, differences in Lf binding capability among strains and between methods used were detected. Binding of Lf was not inhibited by transferrin (Tf) and Lf moiety molecules (mannose, galactose, and lactose) but by Lf. This study demonstrates that S. dysgalactiae bound to bovine Lf in a specific manner.

Topics: Animals; Avidin; Binding, Competitive; Biological Assay; Biotin; Biotinylation; Cattle; Enzyme-Linked Immunosorbent Assay; Lactoferrin; Mastitis, Bovine; Streptococcal Infections; Streptococcus

Human whole saliva induces aggregation of Streptococcus mutans cells via an interaction between a surface protein antigen (PAc) of the organism and salivary agglutinin. Bovine milk inhibits the saliva-induced aggregation of S. mutans. In this study, the milk component that possesses inhibitory activity against this aggregation was isolated and found to be lactoferrin. Surface plasmon resonance analysis indicated that bovine lactoferrin binds more strongly to salivary agglutinin, especially to high molecular mass glycoprotein, which is a component of the agglutinin, than to recombinant PAc. The binding of bovine lactoferrin to salivary agglutinin was thermostable, and the optimal pH for binding was 4.0. To identify the saliva-binding region of bovine lactoferrin, 11 truncated bovine lactoferrin fragments were constructed. A fragment corresponding to the C-terminal half of the lactoferrin molecule had a strong inhibitory effect on the saliva-induced aggregation of S. mutans, whereas a fragment corresponding to the N-terminal half had a weak inhibitory effect. Seven shorter fragments corresponding to lactoferrin residues 473-538 also showed a high ability to inhibit the aggregation of S. mutans. These results suggest that residues 473-538 of bovine lactoferrin are important in the inhibition of saliva-induced aggregation of S. mutans.

Topics: Agglutinins; Animals; Bacterial Outer Membrane Proteins; Cattle; Female; Humans; Lactoferrin; Milk; Protein Binding; Saliva; Streptococcal Infections; Streptococcus mutans

To determine whether lactoferrin (LF) or milk influenced adherence of Streptococcus uberis to bovine mammary epithelial cells.. Three strains of S uberis from cows with mastitis, pooled milk samples from 3 clinically healthy Jersey cows early in the lactation period, and bovine mammary epithelial cells from a clonal cell line.. Adherence of S uberis to bovine mammary epithelial cells in the presence of various concentrations of LF or milk and after pretreatment of bacteria with LF or milk was tested. Bacteria were cultured with mammary epithelial cell monolayers for 1 hour. The culture supernatant was removed, and the epithelial cells were lysed. Adherence index was calculated as number of colony-forming units (CFU) in the cell lysate divided by number of CFU in the supernatant times 10,000.. All 3 strains of S uberis were found to bind to purified LF and LF in milk. Addition of LF to the culture medium enhanced adherence of all 3 strains to mammary epithelial cells, whereas addition of milk enhanced adherence of 2 strains and decreased adherence of the third. Pretreatment of bacteria with LF or milk increased adherence of 1 of the strains but decreased adherence of the other 2. Increased adherence was antagonized by rabbit antibovine LF antibody.. Results suggest that LF may function as a bridging molecule between S uberis and bovine mammary epithelial cells, facilitating adherence of the bacteria to the cells.

Topics: Alkanes; Animals; Bacterial Adhesion; Blotting, Western; Cattle; Colony Count, Microbial; Electrophoresis, Polyacrylamide Gel; Epithelial Cells; Female; Fluorescein-5-isothiocyanate; Immune Sera; Lactoferrin; Mammary Glands, Animal; Mastitis, Bovine; Milk; Rabbits; Streptococcal Infections; Streptococcus; Surface Properties

The lactoferrin (LF) concentration in the milk from dairy cows with clinical mastitis was determined to evaluate the relationship between the LF concentration (LFC) in milk and the non-specific defensive capability of the udder. The mean LFC in 368 milk samples from 319 cows with clinical mastitis was significantly higher (p < 0.01) than that of normal cows. The mean LFC in milk from quarters infected with Mycoplasma bovis or Staphylococcus aureus was significantly higher (p < 0.05) than that of quarters infected with coagulase-negative staphylococci (CNS). In Escherichia coli mastitis, the level of LFC in milk from cows with peracute mastitis was significantly lower (p < 0.01) than that from cows with acute mastitis. In cases of mastitis due to E. coli, the mean LFC in milk from cows that needed more than 10 days to recover from the mastitis or were not cured was significantly lower (p < 0.05) than that for cows which took less than 10 days to be cured. The mean LFC in milk from cows with peracute E. coli mastitis was significantly lower (p < 0.05) than that for cows with mastitis associated with environmental streptococci or CNS, although these low LF levels were somewhat increased after 46 h from the occurrence of mastitis. These results suggest that the decreased levels of LF in peracute E. coli mastitis may be associated with the progress of inflammation in the early phase of mastitis.

Topics: Animals; Cattle; Escherichia coli; Escherichia coli Infections; Female; Immunodiffusion; Lactoferrin; Mastitis, Bovine; Milk; Mycoplasma; Mycoplasma Infections; Staphylococcal Infections; Staphylococcus aureus; Streptococcal Infections; Streptococcus

Bovine lactoferrin is an iron-binding protein present in mammary gland secretions. The exposure of Streptococcus agalactiae to bovine lactoferrin resulted in the binding of this protein to all the 12 strains of bovine origin tested, and also, although to a lesser degree, to the five tested strains of human origin. The interaction of lactoferrin with one high-binding bovine strain (24/60, the prototype NT/X strain) was studied. Binding was time-dependent, dose-dependent, and saturable. The binding of lactoferrin was slightly affected by cultivation conditions, and appeared to be heat-stable. The binding of biotinylated lactoferrin was inhibited by unlabelled lactoferrin but not by bovine serum albumin.

Topics: Animals; Binding, Competitive; Cattle; Female; In Vitro Techniques; Kinetics; Lactoferrin; Mammary Glands, Animal; Mastitis, Bovine; Protein Binding; Streptococcal Infections; Streptococcus agalactiae

Cell-free, fat-free mammary secretions were tested in vitro for ability to support growth of streptococci associated with mastitis. Secretions were obtained prior to drying off, during the dry period, at calving, and during lactation from four cow treatment groups. Treatment groups were dry cow therapy, dry cow therapy and mammary glands subjected to induced inflammation 7 d post-drying-off, no dry cow therapy and no induced inflammation, no dry cow therapy but mammary glands subjected to induced inflammation. Growth of Streptococcus uberis, Streptococcus faecalis, and Streptococcus agalactiae in secretions from nonlactating glands was unaffected by induced inflammation. Growth of Streptococcus bovis was significantly inhibited in secretion obtained 14 d after induced inflammation. Dry cow therapy had no effect on streptococcal growth in secretion obtained 7 d after therapy. Streptococcal growth was greatest in secretions from involuted glands, and there was little or no evidence for growth inhibitory factors in cell-free, fat-free secretions obtained during the dry period. Milk from lactating glands inhibited streptococcal growth, and the inhibitory factor was presumptively identified as lactoperoxidase. Apolactoferrin, immunoglobulin, or both had little effect on streptococcal growth.

Topics: Animals; Apoproteins; Bacteriological Techniques; Body Fluids; Cattle; Citrates; Citric Acid; Culture Media; Disease Susceptibility; Female; Immunoglobulins; Inflammation; Lactation; Lactoferrin; Mammary Glands, Animal; Mastitis, Bovine; Milk; Novobiocin; Pregnancy; Streptococcal Infections; Streptococcus

The mean lactoferrin (Lf) concentration determined by electroimmunodiffusion (EID) assay of whey preparations from 80 quarters of 20 normal lactating cows was 0.35 mg/ml. The mean alpha-lactalbumin (alpha-LAC) and bovine serum albumin (BSA) concentrations were 2.01 mg/ml and 0.29 mg/ml, respectively. The mean was significantly related to cell count (P smaller than 0.01), BSA (P smaller than 0.05), stage of lactation (P smaller than 0.05), and milk production (P smaller than 0.05). The Lf-milk production relationship was the only negative correlation. In 11 cows with mastitis, there was a significant (P smaller than 0.01) increase in mean Lf concentration in infected quarters from 0.55 mg/ml on day 1 of the infection to 1.89 mg/ml by day 3. By day 15 clinical signs had subsided and mean Lf concentrations had decreased to near day 1 values. On day 3 quarters infected with coliform bacteria (clinical mastitis generally more severe) had mean Lf values more than twofold greater than those quarters infected with species of Staphylococcus or Streptococcus (milder clinical signs). Noninfected (control) quarters of cows having coliform bacteria-infected quarters had slightly increased mean Lf concentrations, where Lf concentration in contral quarters of cows having quarters infected with gram-positive organisms remained unchanged.

Topics: Animals; Cattle; Electrophoresis, Polyacrylamide Gel; Escherichia coli Infections; Female; Lactalbumin; Lactation; Lactoferrin; Lactoglobulins; Mastitis, Bovine; Milk; Pregnancy; Serum Albumin, Bovine; Staphylococcal Infections; Streptococcal Infections