Calcium dependent or independent pathway for antibody response against sheep red blood cells in various indigenous and imported breeds of chicken

摘要

Birds (433), 7-week-old, of both sexes belonging to Indian native breeds including Aseel, Kadakanath, Naked Neck and Frizzle fowl along with the exotic breeds like Dahlem red, White Leghorn, Synthetic Dam Line (SDL) and Naked Neck broiler were utilized to test the complement response (expressed as CH50 unit/ml) to sheep erythrocytes determined by means of both calcium dependent pathway or classical pathway (CPW) and calcium independent pathway or alternate pathway (APW). The effect of genotype (breed), sex and their interactions on antibody response was also studied. The results revealed the presence of natural CPW and APW antibodies on day of immunization in all groups under study irrespective of sex. The natural APW response was highest in Aseel and lowest in broilers. The highest CPW responses were observed in Dahlem red and Aseel followed by Kadakanath, Naked Neck, White Leghorn, Frizzle, SDL broiler and NN broiler on day 5 p.i. Aseel had the highest level followed by Kadakanath, but Dahlem Red showed much regressed value on day 12 p.i. and also on day 19 p.i. In all the genetic lines peak response was observed on 5th day p.i. and declined thereafter. Aseel, which showed highest response on day 5 p.i. for APW response also had the highest value on day 12 p.i. and 19 p.i. and lowest response was observed in broilers. Males excelled the females for APW response at all days of measurements post immunization in all genetic groups except Dahlem Red and NN broiler on 12th day p.i. Statistical analysis revealed significant variation in CPW and APW response among the various genetic groups and this remained consistent in all days of post immunization i.e. on day 0,5,12,19 p.i. Sex effects were not significant in any days of p.i. for C.P.W response. Sex effects were significant on days 12 and 19 p.i. only. However, interaction between breed and sex were significant on days 5, 12, and 19 p.i. for CPW and for APW, on days 0 and 19 p.i. It is concluded that the chicken populations utilized in this study differed widely with respect to their immunocompetence traits, on different days of post SRBC injection and observed higher antibody than young birds.