Evaluation of haematocrit, thermoregulation and in vitro hsp70 gene expression in selected and control broiler lines

Effect of selection for juvenile growth on packed cell volume (PCV%), thermoregulatory ability, susceptibility to ascites and in vitro HSP70 gene expression was studied in PB-2 strain and control line of broiler chickens. Body weights at 3 and 5 weeks of age were significantly higher in PB-2 strain than control line and males had higher body weight than females in both the lines at 5 weeks of age. Means for PCV% were similar in two strains, PB-2 strain females had significantly lower PCV % than males of PB-2 strain and females of control line. Mean RV: TV ratio was significantly higher in PB-2 strain (0.24) than control line (0.21) and both the sexes of PB-2 strain had significantly high ratio of right ventricle to total ventricle ratio (RV: TV) than control line. Both the strain had similar surface and core temperatures during morning and control line had higher core temperature during afternoon. In both the strain males had higher surface and core temperature than respective females counter partners. The surface to core temperature ratio, which is indicative of maintenance of warmth in extremities in relation to body were similar in two strains at morning and evening. In vitro HSP70 gene expression increased temperature with increased in temperature and expression was higher in control line as compared to PB-2 strain.