ABSTRACT
Present experiment was conducted to examine whether the supplementation of different organic sources of Cr (Chromium) would improve the performance of heat-stressed calves. Twenty-four female Hariana calves were divided into four treatments (six calves per treatment): (1) calves fed on basal diet (0 mg Cr/kg DM); (2) calves fed on basal diet supplemented with 1.0 mg Cr/kg DM as Cr-picolinate (Cr-Pic); (3) calves fed on basal diet supplemented with 1.0 mg Cr/kg DM as Cr-polynicotinate (Cr-Polynic); and (4) calves fed on basal diet supplemented with 1.0 mg Cr/kg DM as Cr-yeast (Cr-Yeast). Supplementation of different sources of organic Cr did not alter the physiological response of heat-stressed calves during 120 days of feeding experiment. Different Cr sources did not have any effect on liver function test, protein turn over, plasma cholesterol, glucose, total immunoglobulin (Ig) and cortisol levels. Cr shows beneficial effects on cholesterol metabolism, antioxidant activity and plasma concentration of Zn and Cr. Adding Cr-Polynic in the diet of heat-stressed calves significantly reduced (p < 0.05) plasma insulin concentration. This study suggests that the supplementation of different sources of Cr at 1.0 mg/kg DM (Dry Matter), improves antioxidant status and potency of insulin action in heat-stressed dairy calves.
Acknowledgments
The authors would like to thank the staff of the Department of Animal Nutrition, Department of Veterinary Pharmacology and Toxicology, and Instructional Livestock Farm Complex, Veterinary University, Mathura, India. The authors also gratefully acknowledge Dr. Yajuvendra Singh and Dr. S. P. Singh for their assistance during feeding trial.
Disclosure statement
No conflict of interest was reported by the authors.