ovalbumin and Poultry-Diseases

Chlamydia gallinacea is an endemic Chlamydia agent in poultry with a worldwide distribution. The aim of this study was to investigate whether C. gallinacea can be transmitted via fecal-oral, respiratory and vertical routes. After co-housing with C. gallinacea-inoculated broilers (n = 10) for 15 days, over 90.0% of SPF broilers (n = 10) became C. gallinacea-positive in their oropharyngeal and cloacal swabs. Connection of isolators with ventilation tubing resulted in transmission of infectious bronchitis virus, but not of C. gallinacea, from infected broilers in one isolator to uninfected ones in the other isolator. Chlamydia-qPCR determined that 97.6% of shells of embryonated eggs (287/294) from a breeding farm were positive for C. gallinacea. C. gallinacea positivity in egg albumen increased significantly from 7.6% (10/128) before incubating to 44.4% (8/18) of 7-day incubation, and from 5.5% (7/128) to 38.9% (7/18) in egg yolk. After incubating for 19 days, C. gallinacea DNA was detected in heart (5/55, 9.1%), liver (3/55, 5.5%), spleen (7/55, 12.7%), lung (6/55, 10.1%), kidney (8/55; 14.5%) and intestine (4/55, 7.3%) of chicken embryos. Taken together, our data indicate that C. gallinacea can be efficiently transmitted by the fecal-oral route, but not via aerosol. Additionally, vertical transmission can occur via penetration of C. gallinacea from eggshell to albumen, yolk, and the growing embryo. Our findings provide essential information for the control of C. gallinacea in poultry farms.

Topics: Animals; Chickens; Chlamydia; Chlamydia Infections; DNA, Bacterial; Egg Shell; Feces; Heart; Infectious Disease Transmission, Vertical; Liver; Mouth; Ovalbumin; Ovum; Poultry; Poultry Diseases

Myeloblastosis-associated virus type 1 (MAV-1) is an exogenous avian retrovirus with oncogenic potential. MAV-1 was detected in young chicks hatching from eggs produced by an experimental genetic line of egg-type chickens. Transmissibility of MAV-1 had not been documented previously. This investigation was intended to partially characterize the virus involved and to study its transmissibility and oncogenicity in naturally and contact-infected chickens. Commercially produced white and brown layer pullets free of exogenous avian leukosis viruses were commingled at hatch with naturally MAV-1-infected chickens. The original MAV-1-infected chickens were discarded after approximately 8 wk, and the contact-exposed chickens were maintained in isolation for 36 wk. Young specific-pathogen-free (SPF) single comb white leghorn chickens were added to the group to study possible horizontal transmission of MAV-1 in young chickens. Upon weekly virus isolation attempts, MAV-1 was readily isolated from the contact-exposed white layers but not from the brown layers between 36 and 53 wk of age (18 wk in total). Three-week-old SPF chickens were readily infected with MAV-1 by contact as early as 1 wk postexposure. Throughout 22 hatches derived from the white and brown MAV-1-contact-exposed layers (between 36 and 53 wk of age), MAV-1 was frequently detected in the white layer progeny, whereas the virus was seldom isolated from the progeny produced by the brown layers during the same 18-wk period. MAV-1 induced a persistent infection in some of the SPF chickens that were exposed by contact at 3 wk of age. Gross tumors were not detected in any of the originally infected experimental chickens at 8 wk of age, in the contact-exposed brown or white layers at the termination of the study at 53 wks of age, or in the contact-exposed SPF chickens at the end of the study at 12 wk of age. Exogenous avian leukosis-related viruses may still be detected in egg-type chickens, emphasizing the importance of thorough screening before incorporation of experimental genetic material into commercial genetic lines of egg-type chickens.

Topics: Animals; Antibodies, Viral; Avian Leukosis; Avian Myeloblastosis Virus; Chickens; DNA, Viral; Enzyme-Linked Immunosorbent Assay; Female; Male; Ovalbumin; Phylogeny; Poultry Diseases; Sequence Analysis, DNA; Specific Pathogen-Free Organisms; Viremia

A liquid chromatographic method was developed for the determination of ciprofloxacin, enrofloxacin, and sarafloxacin at 10-200 ppb in both egg yolk and egg albumen of laying hens. Egg yolk or albumen was acidified with 1 M phosphoric acid followed by deproteination with acetonitrile and centrifugation. The supernate was pipetted out, and the remaining protein pellet was extracted three times with acetonitrile. The supernates were combined and concentrated at 50 degrees C to <0.7 mL. The final volume was adjusted to 2 mL with 0.02 M potassium phosphate buffer, pH 2.5. Separation of the analytes was achieved using reversed-phase HPLC with fluorometric detection. The recoveries were >80% and coefficients of variation <20%. After validation, the method was applied for use in a national survey for fluoroquinolones in table eggs. Of the 276 eggs assayed, none was found positive for fluoroquinolones. The findings suggest that illegal use of fluoroquinolones in laying hens is not widespread.

Topics: Animals; Anti-Infective Agents; Chickens; Chromatography, High Pressure Liquid; Ciprofloxacin; Egg Yolk; Enrofloxacin; Female; Fluorometry; Fluoroquinolones; Ovalbumin; Poultry Diseases; Quality Control; Quinolones; Veterinary Drugs

The effects of F-strain Mycoplasma gallisepticum (FMG) inoculation during the pullet period on the subsequent performance and egg characteristics of commercial Single Combed White Leghorn hens were evaluated. In two trials, BW, feed consumption, egg production (EP), egg weight, egg size class, relative eggshell water vapor conductance, and relative percentages of eggshell, yolk and albumen weights were determined through approximately 60 wk of age. In each trial, pullets at 12 wk of age were randomly assigned to negative pressure biological isolation units. Birds in one-half of the total units were inoculated with FMG, and the other half were sham-inoculated with sterile media. In both trials, onset of lay was delayed approximately 1 wk in layers inoculated with FMG. Control birds that had not been previously inoculated with FMG laid their first egg at 18 wk of age, while birds that had been previously inoculated with FMG laid their first egg at 19 wk of age. In Trial 1, FMG-inoculated hens laid significantly fewer total eggs, which became apparent at each week after Week 42. In Trial 2, a numerical decrease in total EP occurred, and the percentage of undersized eggs laid by FMG-inoculated birds was significantly lower at 19 wk of age but was higher at 20 and 21 wk when compared to controls. Mortality was not significantly different between the treatments in either trial. These data demonstrate that when birds are housed in isolation facilities and inoculated with FMG at 12 wk of age, onset of lay is delayed. These data also suggest that FMG may lead to delays in undersize EP and decreases in total EP. However, because significant FMG effects on these parameters were observed in only one trial, additional studies may be necessary to verify these effects.

Topics: Aging; Animals; Chickens; Eating; Egg Shell; Egg Yolk; Eggs; Female; Mycoplasma Infections; Ovalbumin; Oviposition; Poultry Diseases

1. The course of infection by exogenous avian leukosis virus was followed in a commercial strain of White Leghorn domestic fowls by measuring viral antigen in feather pulp and egg albumin. Ten days after hatching, 2 out of 360 birds tested positive and at 286 days of age about 60% of the birds had been antigen positive at least once. 2. Among the antigen positive birds, two groups could be distinguished: those which permanently and those which transiently expressed viral antigen. Permanent antigen expression was associated with low antibody titres, while transient antigen expression was associated with high antibody titres. 3. The strain segregated for the two endogenous viral genes ev6 and ev9, both of which express endogenous viral envelope protein, and have been implicated in affecting immune-responsiveness. The antibody titre in individuals positive for both ev6 and ev9, was significantly lower than in those which had none or only one of the two ev-genes. In addition, individuals positive for both ev-genes occurred more frequently in the group permanently positive for viral antigen than in the group transiently antigen positive. 4. The results indicate that there was a strong synergism between ev6 and ev9 in reducing the antibody response to exogenous avian leukosis virus infection, perhaps by inducing immune tolerance or interfering with antibody formation.

Topics: Animals; Antibodies, Viral; Antigens, Viral; Avian Leukosis; Avian Leukosis Virus; Chickens; Enzyme-Linked Immunosorbent Assay; Feathers; Genes, Viral; Immune Tolerance; Immunity; Immunoglobulin G; Ovalbumin; Poultry Diseases

On the basis of earlier studies, a programme for eradicating exogenous avian leukosis virus from commercial poultry stock was devised and applied to 11 layer breeder lines. After three years of testing, avian leukosis virus infection was eradicated completely from all but one, a slow-feathering line.

Topics: Animals; Avian Leukosis; Avian Leukosis Virus; Chickens; Enzyme-Linked Immunosorbent Assay; Female; Ovalbumin; Poultry Diseases; United Kingdom; Vaginal Smears

The association of subclinical infections with lymphoid leukosis virus and performance was investigated in a randombred White Leghorn type population. The proportion of birds shedding group specific (gs) antigen into their egg albumen was high (23.8%). Birds with gs antigen in their albumen matured later, produced fewer and smaller eggs, and grew less rapidly tha their nonshedding counterparts.

Topics: Animals; Antigens, Viral; Avian Leukosis; Avian Leukosis Virus; Body Weight; Chickens; Complement Fixation Tests; Female; Male; Ovalbumin; Oviposition; Poultry Diseases

The induction of avidin in chick tissues was found in septic Escherichia coli infection. Avidin concentrations in the plasma roughly corresponded to those in the other tissues studied which suggests that avidin in chicks is a secretory protein.

Topics: Animals; Avidin; Chickens; Escherichia coli Infections; Ovalbumin; Poultry Diseases

Studied was the effect of tiamin at the rate of 50 mg/kg mixture and white of egg in ratios of 25 and 50 per cent to the feed on the course of coccidiosis in chickens caused by Eimeria tenella. It was found that those of the birds that were offered 25 per cent white of egg and tiamin in a dose of 100 mg per kg exhibited more severe signs of coccidiosis had more pronounced morphologic changes with a higher mortality rate and the amount of the oocysts shed was higher than the same indices in birds having received the vitamin at the rate of 50 mg per kg and white of egg in a ration of 50 per cent to the feed. The increase of white of egg up to 50 per cent led to a lower oocyst production, however, still the latter was higher than in the control birds that were not given white of eggs and vitamin. Cyclicity was observed as well as explosive shedding of oocysts, which was associated with the physiology of the caecal intestines and with the biology of the parasite.

Topics: Animal Feed; Animals; Chickens; Coccidiosis; Dose-Response Relationship, Drug; Drug Evaluation; Eimeria; Ovalbumin; Parasite Egg Count; Poultry Diseases; Thiamine; Time Factors

The incorporation of L-methionine-3H(G) and L-lysine-4,5'3H(n) into egg albumen by dwarf and non-dwarf White Leghorn hens was studied together with the influence of exogenous triiodothyronine (T3) and tetraiodothyronine (T4) on those incorporation patterns. The results were influenced by the amino acid studied and by the strain of bird. The maximum uptake of methionine was a day 1 for the normal and at day 4 for the dwarf which suggested that the dwarf was storing methionine in the tissue first before incorporation into albumen. If the birds were given T3 the maximum for the normal was at day 1 and day 3 for the dwarfs. When T4 was given the maximum uptake was found at day 5 for normals, and at day 2 for dwarfs. In the dwarf, T4 administration essentially corrected the decreased rate uptake of methionine but markedly retarded its uptake by the normal birds. The results for lysine were quite different. The maximum uptake was on day 4 in control, day 3 for T3-treated and day 1 for T4-treated, normal birds. In dwarf birds, the maximum was at day 2 for the control and T4-treated, and day 4 for T3-treated groups. The data were interpreted to suggest strain differences in amino acid uptake patterns due to different rates of synthesis or composition of egg albumen and marked differences in response or recptor sites to thyroid hormones.

Topics: Amino Acids; Animals; Chickens; Dwarfism; Eggs; Female; Genes, Recessive; Ovalbumin; Poultry Diseases; Sex Chromosomes; Thyroid Gland; Thyroid Hormones; Thyroxine; Triiodothyronine

Topics: Animals; Antigens; Carrier Proteins; Chick Embryo; Chromatography, Gel; Eggs; Flavin Mononucleotide; Flavins; Genes, Recessive; Heterozygote; Immunodiffusion; Immunoelectrophoresis; Metabolism, Inborn Errors; Methods; Mutation; Ovalbumin; Poultry Diseases; Rabbits; Riboflavin

Topics: Animals; Bronchitis; Calcium; Chickens; Egg Yolk; Female; Hydrogen-Ion Concentration; Magnesium; Ovalbumin; Oviducts; Ovulation; Ovum; Potassium; Poultry Diseases; Proteins; Sodium; Virus Diseases

Topics: Animal Feed; Animals; Chickens; Diet; Eggs; Heart Diseases; Ovalbumin; Potassium; Poultry Diseases; Sodium; Turkeys

Topics: Amino Acids; Animals; Buffers; Carbohydrates; Cellulose; Chemical Phenomena; Chemistry; Chickens; Chromatography, Ion Exchange; Cold Temperature; Drug Stability; Electrophoresis; Female; Galactose; Genes, Recessive; Glucosamine; Homozygote; Hydrogen Peroxide; Hydrogen-Ion Concentration; Mannose; Metabolism, Inborn Errors; Methods; Molecular Weight; Mutation; Osmolar Concentration; Ovalbumin; Poultry Diseases; Protein Binding; Proteins; Riboflavin; Sulfides; Time Factors; Tryptophan; Ultracentrifugation

Topics: Animals; Chickens; Lactones; Newcastle Disease; Newcastle disease virus; Ovalbumin; Poultry Diseases; Viral Vaccines