Replacing the Concentrate Feed Mixture with Moringa oleifera Leaves Silage and Chlorella vulgaris Microalgae Mixture in Diets of Damascus Goats: Lactation Performance, Nutrient Utilization, and Ruminal Fermentation

SIMPLE SUMMARY: Moringa oleifera and Chlorella vulgaris microalgae have a good balance of amino acids with high protein contents; however, complementary and synergic effects between proteins can improve their nutritive value compared to the individual additive. Replacing a concentrate mixture at 20% to 40% levels with a mixture of M. oleifera and microalgae improved nutrient digestibility, ruminal fermentation characteristics, milk production, composition and the fatty acid profile of goats. Inclusion of M. oleifera and microalgae mixture to partially replace concentrates may enhance milk production performance and milk quality without affecting animal health. ABSTRACT: Exploring suitable alternatives for high-cost concentrate feeds is a critical factor for successful livestock production. The present experiment aimed to evaluate the dietary inclusion of Moringa oleifera silage and Chlorella vulgaris microalgae (at 1% of total diet, DM basis) in a quintuplicate 3 × 3 Latin square design for milk production performance, nutrient utilization and ruminal fermentation in Damascus goats. Fifteen lactating Damascus goats were divided into three groups to be fed a diet composed of a concentrate mixture and rice straw at 60:40 (DM basis) in the control group and fed for 30 days in each period. The concentrate mixture in the control treatment was replaced with M. oleifera silage and C. vulgaris microalgae at 20% (MA20 treatment) or 40% (MA40 treatment). Treatments did not affect total feed intake but increased (p < 0.01) crude protein (CP) and fiber intakes while decreasing nonstructural carbohydrates intake. The digestibility of CP and acid detergent fiber increased due to silage supplementation compared to the control treatment. Treatments increased (p < 0.05) ruminal pH and the concentrations of total volatile fatty acids, acetate, and propionate; however, they decreased (p < 0.05) the concentrations of ammonia-N. Treatments increased (p < 0.05) the concentrations of serum glucose and antioxidant capacity. Both MA20 and MA40 treatments increased the daily milk production, the concentrations of milk fat and lactose, and feed efficiency compared to the control treatment. Additionally, MA20 and MA40 treatments increased the proportions of total polyunsaturated fatty acids and total conjugated linoleic acids. It is concluded that the concentrate feed mixture in the diet of lactating goats can be replaced up to 40% (equals to 24% of total diet) with M. oleifera silage to improve feed intake and nutrient utilization, and milk production performance.