Suitability of raw and heat-treated Amaranthus spinosus in broiler diets: Impact on performance, meat antioxidant capacity, and intestinal health

We assessed the potential of A. spinosus as a feed ingredient for broiler chickens and evaluated the efficacy of heat treatment. A total of 210 male Ross 308 broiler chicks were randomly assigned to five dietary treatments, with six replicates and seven birds per replicate. The control group received a standard mix of maize and soybean meal, and the other groups received diets with varying proportions of raw and heat-treated amaranth, in which up to 10% and 20%, respectively, of the corn and soybean were replaced. Incorporating up to 20% A. spinosus into broiler diets did not have any adverse effects on animal health. We found no significant differences in body weight gain or ultimate body weight between amaranth-fed and control diet-fed birds. However, amaranth addition led to increased feed intake and therefore reduced feed efficiency. Amaranth feeding had no impact on carcass yield or organ weights but the amaranth-fed groups had heavier gizzards, reduced abdominal fat, improved meat antioxidant status, and no adverse effects on blood biochemical or hematological indices. Amaranth grain had no effect on cholesterol levels but decreased triglyceride levels. Heat treatment improved the favorable effects of amaranth on intestinal histology and increased immunoglobulin G levels. The caecal volatile fatty acid profile did not significantly change with amaranth incorporation, and heat-treated amaranth increased caecal branched-chain fatty acid levels and valerate levels in broilers compared to those in raw plants. The data indicate that A. spinosus holds promise as an alternative to traditional grains; digestibility trials are necessary to clarify procedures for further use.