Effect of different temperature humidity indices on antioxidant parameters in Surti buffaloes

The present study was conducted on 20 Surti buffalo heifers of 16 to 21 months age maintained under standard feeding and management practices. They were categorized based on their exposure to natural environment as Group I (Hot dry season: THI ₁), Group II- (Hot humid season: THI₂) and Group III as Control group (Comfortable season: THI₃). Whole blood and serum samples were collected from all the groups and analyzed for antioxidant parameters, viz., superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase, lipid peroxidation (LPO) and total antioxidant status (TAS). The temperature humidity index (THI) calculated for Group I, Group II and Group III were 81.70 (THI₁), 80.30 (THI₂) and 70.00 (THI₃). For Group I, Group II and Group III, concentration of SOD (U) was 5.29±0.06, 4.65±0.04 and 2.94±0.09; GPx (U/ml) was 43.63±0.71, 36.40±0.56 and 25.84±1.00; catalase (μmoles/min/ml) was 1,609.17±45.93, 1,322.00±18.65 and 1,106.35±45.07; LPO (nM of MDA/ml of packed cells) was 6.00±0.13, 3.45±0.09 and 2.87±0.14 and TAS (mmol/l) was 5.18±0.11, 2.90±0.09 and 2.37±0.13, respectively. Significantly (P<0.01) higher levels of SOD, GPx, catalase, TAS and LPO were observed in hot dry season (THI₁) as compared to hot humid (THI₂) and comfortable (THI₃)seasons. Increased levels of SOD, GPx, catalase, TAS and LPO indicated that hot dry season is more stressful for animals as compared to hot humid season in Surti buffaloes astheyareinhabitants of hot humid region.