Discipline: Veterinary Medicine
Pregnant and non pregnant Murrah buffaloes were investigated for oxidative stress due to heat stress by determining changes in blood antioxidant levels. Blood samples were collected from 300 healthy adult females during moderate (Maximum ambient temperature from 25 to 27oC) and hot ambient temperature (Maximum ambient temperature from 45 to 47oC) periods. Serum antioxidants i.e. glutathione, vitamin A and β carotene were determined using a spectrophotometer and the control mean values (μmol L-1) were 5.50±0.03, 2.13±0.02 and 2.49±0.03, respectively. The mean value of each antioxidant in non-pregnant was higher (p≤0.05) than in pregnant animals in moderate ambient temperature period. Heat stress resulted in significant (p≤0.05) decline in the glutathione, vitamin A and β carotene levels in both pregnant and non pregnant animals. However, the magnitude of decrease was greater significantly (p≤0.05) in pregnant animals. This study has shown that heat stress induced oxidative stress in pregnant and non pregnant buffaloes with greater intensity in pregnant animals. The depletion in the levels of antioxidants was perhaps to oppose free radicals generated due to heat stress. This study suggests the need for supplementation of antioxidants in both pregnant and non pregnant buffaloes during heat stress.