A total of 925 pulletts (16 weeks) comprising three strains of White Leghorn (genetically selected strain PL2, a control line, PL3, and a naked neck line); two strains of Rhode Island Red (RIR-B and RIR-C); and two cross bred groups viz; PL2♂ X RIR-B♀ and RIR-B♂ x RIR-C♀ were utilized to evaluate primary antibody response to Sheep Red Blood Cells by haemagglutination test at 0, 5 and 10 days post primary inoculation and to study in vivo cell mediated response to mitogen phytohaemaglutinin (PHA-P). Presence of natural antibodies was evident in all the genetic groups but the differences among genetic groups were statistically non-significant. All groups showed an increase in HA titre upto 10 days post immunization. The HA titre on day 10, was significantly higher in WLh (3.83±0.13) compared to the RIR (3.24±0.15). The crosses between breeds or between strains of the same breed did not exhibit any superiority as indicated by HA titre post primary inoculation. The in vivo cell mediated response to mitogen phytohaemaglutinin response (PHA-P) was highest in the unselected control line (PL3) (0.82 mm) followed by selected strains of WLH and RIR (PL1, PL2, Naked) (RIR-C and RIR-B). The PHA response of WLH was significantly higher than RIR. The crosses did not yield high PHA response than their corresponding pures.
Immune response, SRBC, White Leghorn, Rhode Island Red
