Low level of nutrition and ovarian luteal cyclic activity postpartum in crossbred (Holstein x Zebu) cows

The objective of this study was to evaluate the effect of weight loss on po stpartum cross bred Holstein x Gir (HZ) cows in good body score condition ( BSC = 3.5 to 4.5)at calving on the delay of beginning or on maintenance of ovarian luteal cyclic activity (OLCA). Cows were distributed in three treat ments: Group I(n = 15), maintenance; Group II (n = 10) and Group III (n = 1 3); Groups II and III were feed restricted until 90 and 180 days postpartum , respectively. The weight and BSC were measured after calving and then wee kly. The OLCA was evaluated by rectal palpation, estrous detection and milk progesterone level. Intervals from the calving to first estrous were 53.1, 63.2 and 51.2 days (P > 0.05), respectively, for the Groups I, II and III; weight loss were of 7.3 kg; 57.0 kg and 63.7 kg up to the first estrous, a nd of 14.2 kg, 63.8 kg and 78.4 kg up to 90 days postpartum, for the Groups I, II, and III, respectively. In cross bred (HZ) cows in good body score c ondition at calving, the weight loss of 15.2% of body weight in the first t hree months of milking, and of 16.3% up to 180 days postpartum do not arres t the beginning or impair the maintenance of OLCA.