Distribution of chicken anaemia virus in the reproductive tissues of specific-pathogen-free chickens

The specific-pathogen-free (SPF) Rocks of chickens maintained by the Depart ment of Microbiology and Immunology at Cornell University became infected, inadvertently, with chicken anaemia virus (CAV), as demonstrated by serocon version. Chickens from five Rocks representing three different strains were examined for the presence of CAV using nested PCR. Virus was detected in o varies, infundibula, vas deferentia, testes and spleens. Ovaries were posit ive in 38 to 72% of the hens in four Rocks with 13 to 56 birds examined per Rock. Interestingly, the ovaries were often the only positive tissues, whi le a few hens had only positive spleens. In roosters, the vas deferens was positive in 30 to 79% of the birds with 5 to 19 birds examined per Rock; th e vas deferens was the only positive tissue in 20 to 37%. Individual cells in the theca externa and rare epithelial cells in the infundibular epitheli um were positive for CAV by in situ PCR. Positive cells were not detected i n testes or vas deferentia. The SH-1 strain of CAV was isolated from these tissues and partially sequenced. Only minor sequence differences were found compared to CIA-1 and Cux-1. Embryos from matings between persistently inf ected dams and sire had CAV-positive cells in mesenchyme near the developin g vertebral column. The data show that CAV persists in the reproductive tis sues far longer than previously thought, and that it can be vertically tran smitted from persistently infected birds.