78 Assessing nutrient digestibility in boer×spanish castrated male goats feeding varied levels of hempseed meal

Abstract

Abstract Hempseed meal (HSM) has gained considerable attention as a potential alternative protein source for animal feed in the US, although its FDA approval for this purpose remains pending due to an insufficiency of comprehensive scientific data. The HSM is a byproduct of hemp oil production. Tuskegee University, a ruminant coalition group in the US is assessing this byproduct in meat goats. The present study was designed to investigate the influence of varying HSM inclusion rates on the nutrient digestibility in Boer×Spanish castrated meat goats using a 4×4 Latin square design. Four uniform mature Boer×Spanish castrated goats (14-16 months) were randomly assigned to four treatments. These goats received ad libitum access to experimental diets containing 0%, 10%, 20%, 30% HSM on an as-fed basis. Experimental diets were iso-nitrogenous (crude protein: 16%) and iso-caloric (total digestible nutrients: 64%). The experiment was conducted for 21 d in four phases where 16 d was for diet adjustment and 5 d for sample collection. Feed, feces, and urine were collected during the sample collection period and composited. The feed intake and refusal, fecal and urine outputs were monitored during the sample collection period. The feed, fecal, and urine samples were analyzed for nutrient composition. Nutrient digestibility data were analyzed in SPSS 29 and Microsoft Excel 2021. Our findings revealed no significant differences (P > 0.05) in the digestibility of dry matter, crude protein, crude fat, non-fibrous carbohydrate, neutral detergent fiber, hemicellulose, and ash among experimental groups, except for acid detergent fiber, where a significant difference (P < 0.05) was observed. These results shed light on the potential of hempseed meal in meat-goat diets and emphasize the importance of understanding its impact on specific nutrient digestibility for optimal dietary formulation.