Serological survey on the prevalence of chicken anaemia virus infection in Hungarian chicken flocks.
A serological survey on the prevalence of chicken anaemia virus (CAV) infection was performed by using the indirect immunofluorescence (IF) and the virus neutralization (VN) tests in commercial Hungarian chicken populations. By the indirect IF test, a total of 846 serum samples from 13 meat-type parent flocks of two breeds were investigated between 10 and 62 weeks of age. All flocks were found to be positive for anti-CAV antibodies, and the rates of antibody-positive birds among flocks ranged from 40 to 93.3% and with an average of 73.3%. From nine 1-day- to 9-week-old progeny broiler flocks, 96 serum samples were tested. In the 3 flocks, sampled at the hatchery, 75 to 100% (average 86.4%) of the 22 tested birds were antibody positive. From the 6 flocks, tested between 4 to 9 weeks of age, 3 were antibody negative at 4 and 5 weeks of age, whereas in the 3 remaining 6- to 9-week-old flocks 10 to 20% (average 13.5%) of the birds were antibody positive. In egg-laying parent flocks of 14 and 35 weeks old, 54.4 and 71.7% of the tested 79 and 46 birds had antibodies to CAV, respectively. By the VN test, a total of 670 serum samples from 9 meat-type parent flocks aged between 11 and 37 weeks were investigated. The rate of antibody positivity in flocks was always over 80% and averaged 90.9%. From 7 progeny broiler flocks, 261 serum samples were tested between one day and 7 weeks of age, and the rates of seropositivity in flocks were between 93.3 to 100% and averaged 96.9%. In an egg-laying parent flock, 89.2% of the tested 102 birds had neutralizing antibodies to CAV at 35 weeks old. It was concluded that CAV is widespread in Hungarian commercial chicken populations. Though, according to simultaneous examination of 195 flock sera, the VN test revealed 11.3% more antibody-positive birds, the indirect IF test was found suitable for serological surveys at flock(s) level, provided that sufficient numbers of individual chicks were tested.
Drén
C
C
Veterinary Medical Research Institute, Hungarian Academy of Sciences, Budapest, Hungary.
Farkas
T
T
Németh
I
I
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D017727:Chicken anemia virus / Q000276:immunology; D002645:Chickens / Q000276:immunology / Q000821:virology; D018173:Circoviridae Infections / Q000453:epidemiology / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D005260:Female; D019085:Fluorescent Antibody Technique, Direct / Q000662:veterinary; D006814:Hungary / Q000453:epidemiology; D009500:Neutralization Tests / Q000662:veterinary; D011201:Poultry Diseases / Q000453:epidemiology* / Q000276:immunology / Q000821:virology; D015995:Prevalence
D000914:Antibodies, Viral