Efeito da restrição alimentar e de período de realimentação sobre o desempenho produtivo e eficiência digestiva em caprinos e ovinos

Abstract

This research aimed to evaluate the nutritional efficiency and productive performance of goats and sheep. Thus, we hypothesize that 30% of intake restriction for 28 days does not affect the nutritional efficiency and productive performance of goats and sheep when animals are refed for another 28 days ad libitum. A total of 36 animals were used, in which, eighteen Santa Inês sheep, with an average initial body weight (iBW) of 17.9±1.69 kg, and eighteen Boer goats and with iBW of 18.35±3.46 kg, all males, uncastrated and aged four months. These animals were assigned to a completely randomized design with 6 treatments and 6 replications, using a 3 × 2 factorial scheme. The factorial fixed effects were two species, goat or sheep, and three feeding levels, which were: ad libitum, 15% restriction, or 30% restriction. During the feed restriction period (days 1-28), sheep had higher absolute intake of dry matter, organic matter, crude protein, ether extract, and neutral detergent fiber than goats (P 0.05). Feed restriction did not affect growth performance, but sheep showed greater final body weight (26.6 kg vs. 23.1 kg), average daily gain (157 g/d vs. 85 g/d), and carcass yield (P<0.01). During the feed refeeding period (days 29-56), previously restricted animals showed increased nutrient digestibility, indicating compensatory adaptation (P<0.01). Intake remained higher in sheep, while ether extract digestibility was greater in goats (P<0.01). Despite feed restriction, both species demonstrated compensatory growth, with sheep achieving greater weight gain 4.1 kg due to higher energy intake. These findings suggest that moderate feed restriction does not compromise long-term productivity in growing sheep and goats under a refeeding period.