Submitted to: North Central Avian Disease Conference
Publication Type: Abstract Only
Publication Acceptance Date: October 2, 2001
Publication Date: N/A
Technical Abstract: Avian leukosis virus subgroup J (ALV-J) causes predominately myeloid leukosis in meat-type chickens. ALV-J-induced tumor mortality in commercial broiler breeders can be a major economic loss for the poultry industry. This study was conducted to evaluate the susceptibility of various lines of meat-type chickens following embryo infection with a field strain of ALV- J. Chickens from three different commercial lines along with White Rock and Line 0 chickens were inoculated with strain ADOL 6803 of ALV-J at 7-8 days of embryonic development. At various ages, chickens were tested for ALV-J-induced viremia, cloacal shedding, and virus neutralizing antibodies. Chickens were also observed for ALV-J tumors through the termination of the study at 28 weeks of age. At 8 and 12 weeks of age, the incidence of viremic-tolerant chickens varied from 67%-100%, whereas the incidence of cloacal shedding varied from 32% to 95%. Commercial broiler breeder chickens, regardless of breed were more susceptible to ALV-J-induced tumors (76%-87%) than line 0 and White Rock chickens (50%). Mean age at death from ALV-J- induced tumor ranged from 108-168 days. The data suggest that commercial broiler chickens are more susceptible to ALV-J infection and tumors than chickens of the two experimental lines used in this study, namely line 0 and White Rock.