RESUMO
The present research study was conducted to isolate the chicken egg yolk immunoglobulins [IgY] by chloroform polyethylene glycol [CPEG] technique and to measure antibody titers against avian infection bronchitis [AIB]. For this purpose 300 eggs of broiler breeder were procured from 10 different flocks [30 eggs from each], at least 3 to 4 weeks post-vaccination against avian infectious bronchitis [AIB]. The yolk of three eggs was pooled and subjected to the isolation of IgY by SPEG technique. The concentration of purified IgY was quantified by spectrophotometer and antibody titers against AIB were measured through hemagglutination inhibition [HI] test. Mean concentration of IgY in different flocks ranged from 2.65 to 3.7 g/dl with overall mean of 3.24 g/dl. The geomean antibody titers [GMT] against AIB ranged from 147 to 388 with cumulative GMT of 256. Correlation between concentration of IgY and AIB antibody titers was computed to be 0.88