MVSc

This research work aimed at comparing the immune
responses of indigenous and crossbred cattle of Kerala and finding out association if any, with common diseases and also maternal immune response and the neonatal calf diseases and mortality. Thirty adult local indigenous cattle, their 36 calves, 40 adult crossbred cows and their 40 calves formed the material for the study. Primary humoral response to the test antigen, human red blood cells was assessed at zero, seven and 14th day. Secondary immune response to the test antigen was assessed on day three, seven and 14 after booster injection at 14th day. The antibody titre was assessed by direct microhaemagglutination technique. Cell mediated immune response to contact sensitizer 2,4-Dinitrochlorobenzene (DNCB) was assessed by application of two per cent solution on zero and first day followed by percutaneous challenge at the 14th day. Double fold skin thickness and area of reaction were recorded. Humoral and cell mediated immune response, the influence of genetic group, association with diseases and mortality, influence of maternal immune response on the calf immune response and association with calf diseases and mortality were assessed.
The antibody titres were expressed as 1oge + 1 to make the distribution normal.
Peak primary immune response was
reached by day 14 (2.13) and peak secondary response was on
seventh day of secondary immunization (2.98). No significant

differences were observed between primary and secondary immune
response in different genetic groups namely indigenous and
crossbred cattle and also in different age groups viz. dam and
calf. The correlation between primary and secondary immune
response except in indigenous cows, were highly significant.
The cell mediated immune response peaked by 24th post
2,4-Dinitro chloro benzene challenge both in indigenous and
crossbred cattle (7.0 mm). No significant association could
be detected between the incidence of diseases and mortality
with humoral as wel1 as cell mediated immunity. Similarly
association between maternal and calf immune response was also
not significant. Indigenous cows had lower incidence of
respiratory diseases and mastitis compared to crossbred cattle
(od2 = 3.8 and 19 respectively). Similarly local indigenous

calves had significantly lower mortality (oc2 = 8).
The results of the study suggests that primary immune response could be used as an index of secondary immune
response. The study also suggests that immune response to a
single antigen might not be indicative of general disease
resistance. Further, apart from the immune response traits in the present study, there might be several factors which influence the immune response, disease resistance and disease susceptibility.