Avian Diseases 

About: Avian Diseases is an academic journal published by American Association of Avian Pathologists. The journal publishes majorly in the area(s): Virus & Influenza A virus subtype H5N1. It has an ISSN identifier of 0005-2086. Over the lifetime, 7458 publications have been published receiving 183568 citations.

Evaluation of the heterophil/lymphocyte ratio as a measure of stress in chickens.

Abstract: The number of lymphocytes in chicken blood samples decreased and the number of heterophils increased in response to stressors and to increasing levels of corticosterone in the chicken feed. The ratio of heterophils to lymphocytes was less variable than the number of heterophil or lymphocyte cells, and the range of values for this ratio was greater than the range of values for heterophils and lymphocytes among control and experimental groups. The heterophil/lymphocyte ratio appears to be a more reliable indicator of levels of corticosterone in the feed and to social stress than were the plasma corticosteroid levels.

Increased Virulence of Marek's Disease Virus Field Isolates

Abstract: The continuation of an apparent evolutionary trend of Marek's disease virus (MDV) towards greater virulence may explain recent increased losses from Marek's disease (MD) in vaccinated flocks. To address this question, the virulence of 31 isolates of serotype 1 MDV obtained from layer or broiler flocks between 1987 and 1995 were characterized. Each isolate was cultured in duck embryo fibroblasts for four to six passages, and ascertained to be free from contamination with avian retroviruses, chicken anemia virus, and MDVs of other serotypes. The viruses, along with prototype viruses JM/102W and Md5, were tested for virulence by inoculation at 6 days of age into laboratory strain 15I5 x 7(1) chickens of three types: nonvaccinated, vaccinated with turkey herpesvirus (HVT) and bivalent (HVT + SB-1)-vaccinated. The results showed that three isolates did not differ from JM/102W and were classified in the virulent (vMDV) pathotype. Twenty-one isolates produced significantly higher levels of MD in HVT-vaccinated chickens than did the JM/102W control and were classified in the very virulent (vvMDV) pathotype. Seven isolates, five of which were isolated in 1994 or 1995, produced significantly higher levels of MD in bivalent-vaccinated chickens than did the Md5 (vvMDV) control. These isolates, provisionally designated as the vv+MDV pathotype, appeared to be at the high end of a virulence continuum. Several MD response parameters, including lymphoma mortality, early mortality with bursal/thymic atrophy, and frequency of visceral lymphomas or ocular lesions in nonvaccinated chickens were positively correlated with virulence. These findings support the continued evolution of MDV towards greater virulence.

Fowl cholera; gel diffusion precipitin test for serotyping Pasteurella multocida from avian species

Abstract: SUMMARY Heat-stable antigens extracted with formalinized saline were used in the gel diffusion precipitin test to group Pasteurella multocida associated with fowl cholera into 5 serotypes. Of 258 field isolants tested, 33 were type 1, 157 were type 3, 28 were type 4, 4 were type 5, and 4 were type 6; 27 isolants reacted with type 3 antiserum and to a lesser extent with type 4 antiserum, and 5 isolants did not react with any antisera. Bacterins prepared with P. multocida serotypes 1, 3, and 4 induced good immunity in chickens and turkeys against organisms of the same serotype. A bacterin prepared with serotype 4 culture induced as good immunity against a serotype 5 challenge-exposure culture as was induced with the homologous bacterin. The serological behavior of the heat-stable antigens was compared by gel diffusion and immunoelectrophoresis with partially purified lipopolysaccharide-protein complex (endotoxin) that had induced specific immunity in turkeys. Lines of identity were observed in the gel diffusion test, but a slight difference was observed with immunoelectrophoresis. The heat-stable antigen was demonstrated in the serum of a turkey with acute fowl cholera and in the blood of turkeys that died of the acute disease.

An Apparently New Disease of Chickens: Avian Nephrosis

Abstract: INCE the fall of 1957, in the Delmarva area, we have seen an acute disease of chickens with increasing frequency. This malady, which appears to be infectious and contagious, is characterized by ruffled feathers, watery diarrhea, trembling, and severe prostration. It seems to spread from pen to pen within a poultry house, and tends to recur in successive broods. The initial outbreaks occurred in and around an area known as Gumboro, in southern Delaware; hence, the common name of "Gumboro disease." The term avian nephrosis has been applied to this new disease because of the tubular degenerative lesions in the kidneys. Specific characteristic signs and lesions set off the condition as a definite entity.