Green propolis extract replaces salinomycin in the high-concentrate diet of sheep

This study aimed to evaluate the effects of supplementing high-concentrate diets for sheep with green propolis extract (PRO) from Mimosa tenuiflora or with salinomycin (SAL) on feed intake, apparent digestibility, nitrogen balance, and water balance. Three sheep, ½ Dorper x ½ Santa Inês, were assigned to a 3 × 3 Latin Square design, repeated over time, totaling six replicates per treatment. The animals were castrated, with a mean age of 26 months and a weight of 47.94 ± 4.73 kg. The treatment diets were control (CON); CON + 24 mg SAL/kg DM (SAL); and CON + 24 mL PRO/day (PRO). The experiment lasted 102 days, each consisting of 17 days of adaptation and five days of data collection. Intake of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber, and non-fibrous carbohydrates did not differ (P > 0.05) between the additives. However, total digestible nutrient (TDN) intake was lower (P < 0.05) for the SAL diet. Similarly, the SAL diet tended to reduce the apparent digestibility of DM (P = 0.0542), OM (P = 0.0573), CP (P = 0.0662), and TDN (P = 0.0836) in sheep. In addition, SAL-fed sheep absorbed and retained less (P < 0.05) nitrogen than those fed the CON and PRO diets. Supplementation with salinomycin at 24 mg/kg DM impairs energy intake and nitrogen utilization by sheep. Supplementation with 24 mL/day of green propolis extract does not affect energy intake and nitrogen use by sheep.