Congenital transmission of avian leukosis virus in the absence of detectable shedding of group specific antigen.

Abstract

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 26/27 hens transmitted ALV. Some of the ALV-transmitting hens in the commercial flock had virus in vaginal swabs thus enabling infection to be detected. The reasons for such a high proportion of congenitally transmitting hens which did not shed detectable amounts of gs antigen in the commercial flock was not determined. In the SPF flock, 2/15 hens ..