Studies on the physiological, biochemical and hormonal response of Mithun (Bos frontalis) bullocks during ploughing and carting operation.

Mithun animals are primarily reared for meat production. However, there is scope for utilizing this majestic animal of North-East India as a draught animal due to its ability to thrive in hilly terrain. There are limited published data on physiological, blood biochemical and hormonal parameters of Mithun bullocks during ploughing and carting operations. The present study was conducted on three Mithun bullocks (castrated males) to evaluate the physiological, biochemical and hormonal responses to ploughing and carting operations. Recording of physiological parameters and blood collection were done before work, immediately after work, and after one hour of rest. Significant differences (P < 0.01) were observed for all physiological parameters between before-work and immediately after-work values during ploughing and carting operations. The respiration rate of Mithun was most greatly affected, followed by pulse rate and rectal temperature during work. The ploughing ability of Mithun was calculated as 28.15%. The fatigue score of Mithun (< 20) indicated that Mithun bullocks can be used efficiently for 2 continuous hours of ploughing. The concentrations of serum glucose, total protein and cortisol increased significantly (P < 0.01) during carting with a 300 kg load (excluding cart weight and cartman weight) for 2 h. However, lactic acid and cortisol values were non-significant between before-work and after-work during ploughing operations, indicating that the animals were physically challenged at the metabolic level but remained within a normal adaptive physiological range without mounting a significant hormonal stress response. The horsepower generated by Mithun bullocks under no-load carting was 0.39 hp.