Effect of ascorbic acid and amla powder (embilica officinalis) supplementation on physiological parameters in cross-bred dairy cattle during heat stress

To study and compare the effect of dietary supplementation of ascorbic acid and amla powder (Embilica officinalis) on physiological parameters during summer, twelve cross-bred dairy cattle were randomly divided into three groups of four animals 4 each. The T1 group was control, T2 and T3 groups were supplemented with ascorbic acid and amla powder @ 50 mg/kg body weight and 200 mg/kg body, respectively. The overall mean maximum and minimum temperature recorded during the study were 38.68±2.43°C and 26.45±2.13°C, respectively, while the overall mean relative humidity and temperature humidity index (THI) recorded at 0800 hrs and 1400 hrs were 81.32±5.21%, 74.06±3.92, and 51.31±4.93%, 87.60±4.32, respectively. Rectal temperature (RT), respiratory rate (RR) and pulse rate (PR) were non-significant between different treatments during 0800 hrs, while corresponding values at 1400 hrs were significantly (P<0.01) higher in T1 (39.91±0.36°C, 62.05±3.69 breaths/minute, and 90.25±5.22 beats/minute) than T2 (39.1±0.45°C, 50.92±3.77 breaths/minute and 77.08±4.71 beats/minute) and T3 (39.17°C±0.46°C, 52.97±3.85 breaths/minute and 78.68±4.36 beats/minute). There was no significant difference between T2 and T3 for all parameters. From this study, it is concluded that supplementation of either ascorbic acid or its equivalent in the form of amla powder @ 50 mg and 200mg/kg BW respectively, can ameliorate the heat stress in dairy cattle.