A survey for parvovirus-like virus (so-called chick anemia agent) antibodies in broiler breeders

A prospective study to survey for the presence of parvovirus-like virus (PVLV; so-called chick anemia agent) antibody in broiler breeder pullets in Georgia, North Carolina, and Florida was conducted by collecting serum samples from 52 breeder flocks that ranged in age from 1 day to 55 weeks old. Results indicated that PVLV infection was widespread. Ninety-eight percent (51/52) of chicken flocks and 62% (530/861) of chickens had PVLV antibody. Rates of antibody-positive chickens among flocks ranged from 0% to 100% and averaged 76%. Upon initial examination, the percentages of chickens positive for PVLV appeared evenly distributed with respect to several convenient age groups and geographic locations. However, compared with young chickens (less than or equal to 19 weeks old), markedly significantly lower proportions of positives were present among chickens more than 19 weeks old (P = 0.00001) or chickens 30 weeks old or more (P = 0.000004). Also, there were significant (F = 7.7, df = 3/827, P less than 0.001) differences among the rates of PVLV antibody in chickens among various companies. The relatively high rate of PVLV antibody among broiler breeder chickens helps explain the low incidence of clinical disease among their offspring.