Alterations in physio-biochemical parameters due to induced chronic heat stress in Sahiwal and Tharparkar cattle

Abstract

AbstractThe intended objective of the present research was to investigate more about the "thermoadaptability of Tharparkar and Sahiwal cattle under induced chronic heat stress". Healthy male animals between the ages of 2.5 and 3 years were chosen for the study and split into two groups (five animals in each group). For the study five Sahiwal cattle and five Tharparkar cattle were selected which included a 7 day acclimatization period, 49 days of heat exposure at 38°C (6 hours each day) and a 7 day recovery period. Recording of Physiological responses like rectal temperature and respiration rate was done on daily basis. During the experimental period it was observed that in Sahiwal group, rectal temperature and respiration rate increased significantly (p < 0.05) in comparison to Tharparkar during heat stress period as compared to control period. The collection of blood was done weekly on -7, 0, 7, 14, 21, 28, 35, 42, 49, 56 days. During the period of heat exposure the level of serum ALT, AST, ALP significantly (p < 0.05) increased in both Tharparkar and Sahiwal breed as compared to control period. The level of serum ALT, AST, ALP was found to be significantly (p < 0.05) higher in Sahiwal group as compared to Tharparkar. During the heat exposure period TAC in both the breeds was significantly (p < 0.05) increased. The level of serum protein during the heat exposure period was significantly (p < 0.05) reduced in both the breeds although no significant (p > 0.05) difference was observed between the breeds. Our findings indicated that the plasma biochemical markers in both breeds are more negatively impacted by heat stress. Additionally, among the native breeds, Tharparkar cattle displayed the least amount of biochemical changes in response to heat exposure and can therefore be regarded as more thermo-adaptable than Sahiwal cattle.