Effect of Dietary Selenomethionine Supplementation on Growth Performance, Tissue Se Concentration, and Blood Glutathione Peroxidase Activity in Kid Boer Goats

We used 240 kid Boer goats that were divided into six groups. The control group was fed a basal diet containing 0.05 mg of selenium (Se)/kg dry matter (DM). Trial groups received the basal diet supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5 mg Se/kg DM (using a commercial selenomethionine product). Trial groups showed an improvement in growth performance (P< 0.05) despite no change in average daily feed intakes (ADFIs) (P> 0.05) compared to the control group A, quadratic model showed a correlation between glutathione peroxidase activity level in whole blood and dietary Se concentration (R-2= 0.883, P< 0.04). The best linear model showed that increasing concentrations of Se in the blood (R-2= 0.968, P< 0.001) and muscle (R-2= 0.942, P< 0.001) corresponded to increasing Se concentrations in feed. Accumulation of Se in different tissues and organs corresponded to increasing Se concentrations in the diet as well as to the total time goats spent feeding on supplemented diet. Kidney and muscle tissues showed the highest and lowest accumulation of Se, respectively. Thus, Se in goat meat can be increased by adding between 0.1 and 0.5 mg/kg of selenomethionine to the diet of goats.