Effects of soybean hulls and sunflower hulls as alternative fiber sources in complete pelleted diets on feed intake, metabolic status, and reproductive performance of naemi ewes

This study evaluated replacing wheat straw (WH) with alternative agricultural by-products, soybean hulls (SBH) or sunflower hulls (SFH), in complete pelleted diets and their effects on feed intake, metabolic status, and reproductive performance of Naemi ewes. Sixty-three ewes (40.0 ± 4.8 kg body weight, 7–8 months) were randomly assigned to three dietary treatments over a 270day. Measurements included dry matter intake, body weight, body condition score, reproductive indices, and serum glucose and non-esterified fatty acids (NEFA). Fiber source affected feed intake during specific reproductive stages (p < 0.05), with SBH diets leading to higher intake during mid-gestation and early postpartum. Ewes fed SBH had higher body weight during late gestation and early lactation (p < 0.05). Reproductive rates pregnancy, lambing, and fecundity were highest in SBH group, while lamb survival was lower in the SFH group (p < 0.05)., SBH group had lower serum NEFA concentrations during late gestation (p < 0.05), indicating a less negative energy balance. In conclusion, both by-products can physically replace traditional forage, with SBH being a superior fiber source. Incorporating SBH into complete pelleted feeds provides a practical solution to preserve maternal body reserves, improve periparturient energy balance, and enhance flock reproductive performance in semi-arid production systems, although more long-term researches are needed.