Serologic Profiling of Chickens in Taiwan from 1993 To 1994

Abstract

15,253 serum samples collected from different grandparent (GP) stocks, parent stocks (PS), and broiler flocks in northern Taiwan from March 1993 to June 1994 were tested for the antibodies against Salmollella pullorum (Pullorum disease, PD), MycopLasma gallisepticum (MG), and Mycoplasma synoviae (MS) by plate agglutination test; against egg drop syndrome 76 (EDS-76) and Newcastle disease by hemagglutination inhibition test (HI); and against infectious bursal disease (IBD), infectious bronchitis (IB), reovirus, and infectious laryngotracheitis (ILT) by enzyme-Iinked immunosorbent assay (ELISA). The results of agglutination test indicated that four farms among 5 tested were free from PD while 2 farms were free from MG and MS. In an EDS-76-unvaccinated breeder farm, EDS HI titers ranged from 2^3 to 2^8. In ND-vaccinated breeders the ND HI titers ranged from 2^4 to 2^10. The geometric ELISA titers of the IBD, IB, reovirus, and ILT in breeder farms were 3,000x, to 10,000x, 1,000x to 4,000x, 1,000x to 3,000x, and 1,000x to 2,000x, respectively. In spite of several vaccinations, all tested antibodies in all broilers decreased gradually and did not increase until 5 to 6 weeks of age.