Milk yield and body weight changes during lactation in Jersey crossbred cows of different levels of production in West Bengal

摘要

Jersey X Tharparkar/Red Sindhi cows (78) revealed significant effect of level of milk production (high, medium or low) on monthly milk yield and body weight changes during lactation. The milk yield reached a peak in 2nd month and thereafter showed adeclining trend in all the three groups. The milk production efficiency was more in high producing group (>3000 kg) than the other two groups. Body weight of cows decreased during first four months of lactation and then increased gradually. At the lastphase of lactation, Jersey crosses regained most of the body weight lost during early lactation. Maximum cumulative loss of body weight for high (>3000 kg), medium (2501 - 3000 kg) and low (<=2500 kg) producers occurred during first 4, 5 and 3 months oflactation, respectively. High producers lost maximum (26.2 kg) and the low producers lost minimum body weight during first four months of lactation. The maximum body weight loss occurred during the first month of lactation in all the three groups. Low producing cows regained the entire loss of body weight after the completion of 7 months of lactation and medium producers in 10 months, while the high producing cows recovered the weight loss to a great extent after the completion of 10 months of lactation