Lactation and nutrient digestion of Qianbei Brown goats at different nutrient levels

This study was conducted to examine the effects of the feeding of different nutrient levels on the nutrient digestibility and lactation performance of Qianbei Brown goats to provide a theoretical reference for formulating nutritional requirements and supplementary feeding plans of these goats during lactation. Twenty-seven lactating female sheep with a body weight of (37.8 ± 0.79) kg, that would lamb in (7 ± 1 ) days, and with one to two parities were randomly divided into three groups. The experiment duration was 56 days, the pretest duration was 14 days, and the trial period duration was 42 days. Ewes were fed diets meeting 80%, 100%, or 120% of their nutritional requirements. The effects of these different nutrient levels on ewe weight loss, lamb weight gain, milk yield, nutrient intake, and nutrient digestion and use were determined. The results showed that with the increase in nutrition level, the weight loss of the lactating ewe decreased (P < 0.05) and the lamb weight gain increased (P < 0.05); the milk yield of the ewes increased with the increase in nutrient level (P < 0.05), and the milk fat percentage, milk protein, and lactose contents increased (P < 0.05). Dietary dry matter, organic matter, gross energy, crude protein, neutral detergent fiber, calcium, and phosphorus intake and digestibility increased with the increase in nutrient level (P < 0.05). In conclusion, improving nutrition level can increase ewe lactation, reduce ewe weight loss, increase nutrient intake, improve nutrient digestion and absorption, and promote the lamb growth. The optimum nutritional level for lactating Qianbei Brown ewes is 120% of the nutritional requirements of “Feeding Standard of Meat-producing Sheep and Goats”.