Efeito da nutriçao sobre o desempenho ponderal e a fertilidade de vacas mestiças leiteiras no pós-parto

The objective of this work was to evaluate the effect of nutritional variation upon ponderal performance and the fertility of postpartum crossbred dairy cows, with a good body condition (scores > 3.0) at parturition. Animals were divided into two groups of 24 each and fed on two levels of energy, restricted and normal (respectively, 70 percent and 100 percent of the National Research Council, requirements), 22 days after parturition. Body weight and body condition scores of the cows at artificial insemination were reduced (P <.01), by the level of restriction. The daily milk production was reduced in the cows with restricted diets (P <.01). The intervals from parturition to first estrus and to artificial insemination for cows fed on the restricted and normal levels (34.8 and 34. 1 days and 54.8 and 57.3 days), respectively, were similar (P >.05). Pregnancy rates of cows fed on the restricted level was reduced (37.5 vs 87.5 percent) compared with cows fed on the normal diet. (RA) eng