Effect of nutritional flushing on productive and reproductive efficiency in ewes

The study evaluated dietary flushing on reproductive efficiency in 60 Santa Ines ewes, divided into three groups: (1) no supplementation, (2) 0.50% and (3) 1.00% supplementation of body weight. The supplement contained corn, soybean meal, oats, lime, bicalcium phosphate, mineral mixture, urea and yeast, administered three weeks before and during mating, which lasted for 46 days. Weight, body condition and weight gain were measured at the beginning and end of the feeding period. Milk production, lamb weight and biometric measurements were recorded until weaning. Supplementation did not significantly affect the ewes' weight, body condition indices or milk production. The percentages of twin births were: 19%, 52.9% and 44.4% (P=0.08), respectively for the ewes in the control group and for those that received supplements (0.50% and 1.00%). Lamb weight and biometric measurements were not significantly affected by maternal treatment or the sex of the lamb. Lambs born from single births were heavier than those from twin births (P<0.05), but the combined weights of twins at weaning were higher. Ewes with twins tended (P<0.09) to be more efficient than those with single birth lambs, weaning 41 kg of lambs per 100 kg of ewe weight, compared to 36 kg for single birth ewes. Flushing did not affect ewe weight or milk production, but it did increase the rate of twin births, improving reproductive efficiency.