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.

Influence of Dietary Supplementation of Inorganic and Organic Chromium on Body Conformation, Carcass Traits, and Nutrient Composition in Muscle and Internal Organs of Black Bengal Goats

The effect of dietary inorganic and organic chromium (Cr) on body morphometry, carcass traits, and nutrient composition, including different minerals and fatty acids in meat and internal organs of Black Bengal goats, was studied. Thirty weaned Black Bengal kids of 3-5 months (5.40 ± 0.34 kg body weight) were assigned randomly into five groups and fed additional Cr for 150 days. The experimental diets comprised a basal diet supplemented with Cr at the rate of 0 (control; without Cr supplementation), 1.0 and 1.5 mg/kg of inorganic Cr (Cr(III)-chloride), and 1.0 and 1.5 mg/kg of organic Cr (Cr-yeast). The body morphometry such as body length, heart girth, paunch girth, loin width, leg circumference, and the carcass traits, namely, slaughter body weight, dressing percentage, hind quarter and forequarter weight, and rib eye area of goats, were not significantly (P < 0.05) changed due to inorganic and organic Cr supplementation. However, organic Cr supplementation (1.0 and 1.5 mg/kg) resulted in a reduction of breast and back fat thickness (P < 0.05) compared with the control group. The weights of internal organs including liver, lungs, spleen, kidney, testes, and heart and their weights as a percentage of slaughter weight were similar (P > 0.05) among different experimental groups. Dry matter, ether extract, and total ash concentrations of muscle and internal organs of Cr-supplemented groups were not affected (P > 0.05) by Cr supplementation. However, crude protein contents in the liver, muscle, kidney, and lungs were greater (P < 0.05) in the organic Cr groups than in the control and inorganic Cr groups. In meat (longissimus dorsi muscle), total saturated fatty acid concentration was lower (P < 0.05; 59.4% versus 55.7%) and the unsaturated fatty acid concentration was greater (P < 0.05; 40.6% versus 44.3%) including palmitoleic acid, heptadecenoic acid, elaidic acid, and arachidonic acid in the organic or inorganic Cr-supplemented groups than in the basal diet group. In conclusion, dietary supplementation of organic Cr in Black Bengal goats has no influence on the carcass traits, but may improve the meat quality with greater protein content, lean, and healthier fatty acids for human consumption.