Congenital transmission of avian leukosis virus in the absence of detectable shedding of group specific antigen [chickens]
1990
Ignjatovic, J. (Commonwealth Scientific and Industrial Research Organisation, Parkville (Australia). Div. of Animal Health)
Congenital transmission of avian leukosis virus (ALV) in the absence of detectable amounts of group specific (gs) antigen in egg albumen was found to occur in one commercial and one specific pathogen-free (SPF) flock. The prevalence of congenitally transmitting hens which did not excrete gs antigen was particularly high in a commercial flock where 26 out of 27 hens transmitted ALV. Some of the ALV-transmitting hens in the commercial flock had virus in vaginal swabs thus enabling infection to be detected. In the SPF flock, 2 out of 15 hens congenitally transmitted ALV antibodies to subgroups A or B were not present. This form of ALV-infection persisted in two successive generations. These results indicate the necessity of testing for infectious ALV in embryos, in order to ascertain that a flock is genuinely free of ALV.
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