The Effects of Dietary Inorganic and Organic Chromium Supplementation on Blood Metabolites, Hormones, and Mineral Composition of Blood and Internal Organs in Black Bengal goats

The present study was performed to evaluate the influence of dietary inorganic and organic chromium (Cr) supplementation on blood biochemical constituents and mineral concentrations as well as the changes in the mineral composition of internal organs of Black Bengal goats. Thirty Black Bengal kids of 3 to 5 months (5.40 ± 0.34 kg body weight) were allocated randomly to five treatment groups. The five groups were control (without added Cr in a basal diet), 1.0, 1.5 mg/kg of inorganic Cr, 1.0, and 1.5 mg/kg of organic Cr added per kilogram of feed dry matter. The duration of the experiment was 150 days during which the changes in the blood biochemical and mineral concentrations at 0, 30, 60, and 150 days were evaluated. At the end of the trial, mineral composition in the muscle, skin, and internal organs (liver, lungs, kidney, heart, spleen, and testis) were analyzed. Any blood variables were not affected at or before 60 days of Cr supplementation. Both inorganic and organic Cr supplementation lowered ( P < 0.05) concentrations of blood glucose, cortisol, non-esterified fatty acids, and β-hydroxybutyric acid after 60 days of Cr supplementation. Organic Cr-supplemented groups exhibited higher ( P < 0.05) blood insulin concentration and neutrophil activity compared to the control. Supplementation of Cr in either form had no substantial effect ( P > 0.05) on the blood hemoglobin, total leukocyte count, total protein, albumin, globulin, immunoglobulin G, total antioxidant capacity, and liver enzymes (aminotransferases) concentration, and also blood minerals (zinc, iron, and manganese) concentration. Blood Cr and copper concentrations were increased ( P < 0.05) due to both organic and inorganic Cr supplementation. Minerals (calcium, phosphorus, magnesium, iron, zinc, copper, and manganese) concentrations of internal organs of Cr-supplemented groups were mostly not affected ( P > 0.05) by Cr supplementation. However, the concentrations of Cr and copper in blood and Cr in all internal organs, skin, and muscle of organic Cr-supplemented groups were higher ( P < 0.05) than in those fed the basal diet. In conclusion, dietary inorganic and organic Cr supplementation, especially the organic form, after long term supplementation (> 60 days) could be beneficial in regulating blood glucose and fat metabolism and the immune status of Black Bengal goats.