Upcycling Pomegranate Silage in Dairy Goat Diet over a Full Lactation: Impacts on Productive Performance and Metabolic Responses

Pomegranate by-product silage has potential as a sustainable feed ingredient for ruminants. This study evaluated the effects of including ensiled pomegranate by-product (Punica granatum L., cv. Wonderful) in the diet of Murciano-Granadina dairy goats during a full lactation period. Forty goats were allocated to four groups to test 2 diets (2 treatments × 2 batches): a control diet (conventional diet without pomegranate by-products) and an isoenergetic, isoproteic diet containing pomegranate silage (PS). After a pre-experimental sampling at five weeks post-partum (to collect baseline data), an 8-month experimental phase was carried out. Feed and water intake—every 2 weeks— live weight, milk yield and composition, urea content, and somatic cell count were measured every 6 weeks. Blood samples were obtained at the beginning, midpoint, and end of lactation to assess physiological, metabolic, inflammatory, and oxidative status. Data were analyzed using a mixed linear model. The treatment effects were limited to live weight, which was lower in the PS treatment (p < 0.05), without affecting milk production. In conclusion, ensiled pomegranate by-product can be included without compromising productivity or animal health, representing a sustainable nutritional alternative for dairy goats.