International Journal of Insect and Animal Diversity Research

This review reviews the effects of adding curcumin to ruminant diets, a natural polyphenol extracted from turmeric (Curcuma longa). Literature suggests that it may improve growth performance and feed conversion efficiency, modulate rumen fermentations and microbiome, and reduce oxidative stress by elevating antioxidant enzymes such as SOD, catalase, and glutathione peroxidase. It also exhibits immunological and anti-inflammatory effects, as it reduces the inflammatory cytokines IL-1β, IL-6, and TNF-α, increases IL-10, and affects immunoglobulins and acute phase proteins. Curcumin is relatively safe within 2000 mg/kg feed and has been used in calves up to 320 mg/day, but its bioavailability is low and undergoes extensive metabolism, necessitating higher doses or nanoformulations. Gaps remain about the optimal dosage, methane emission, mechanisms of action, and interactions with nutrients, especially in sheep and goats. Curcumin therefore appears to be a promising supplement for ruminant health and productivity, with independent standardized studies needed.