EXPERIMENTAL EVALUATION OF AN INACTIVATED VACCINE AGAINST CHICKEN ANEMIA VIRUS

An assessment of the performance of an inactivated chicken anaemia vir us (CAV) vaccine following administration to specific-pathogen-free (S PF) breeder hens before the egg production period is reported. Antibod ies to CAV in adult hens and maternally-derived antibodies to CAV in t he progeny chicks were assayed by ELISA. Progeny of vaccinated chicken s showed sufficient levels of maternally-derived antibody to CAV for u p to 3 to 4 weeks of age. Following challenge at 1, 10, 20 and 30 days of age of chicks from CAV-vaccinated and non-vaccinated hens with vir ulent CAV, haematocrit levels and weights of thymus in vaccinates rema ined within normal ranges. Chicks derived from non-vaccinated hens dev eloped anaemia and thymus atrophy following challenge. These results s upport the view that vaccination of breeder flocks with an inactivated vaccine to CAV could be an effective means of control of CAV-induced clinical disease.