I. YANCHEV1, P. MONEVA1, D. GUDEV1, S. POPOVA-RALCHEVA1, Tz. PEEVA2,
P. PENCHEV2 and I. ILIEVA2
1 Institute of Animal Science, BG – 2232 Kostinbrod, Bulgaria
2 Agricultural Institute, BG – 9700 Shumen, Bulgaria
YANCHEV, I., P. MONEVA, D. GUDEV, S. POPOVA-RALCHEVA, Tz.PEEVA, P. PENCHEV and I. ILIEVA, 2008. Effect of Weaning on Some Plasma Metabolites in Black-and-white Calves Fed Diets with or without Supplemental Chromium Picolinate. Bulg. J. Agric. Sci., 14: 329-334
The objective of this study was 2 fold: to determine whether the weaning (abrupt transition from liquid to solid diet) at the age of 90 days causes stress in Black-and-white calves, and if so, to alleviate the negative effect of stress by chromium picolinate supplementation (400 µg daily). All calves were separated from their mothers immediately after birth. Chromium supplementation started 3 days before the weaning and was terminated 5 days later.
Plasma cortisol levels in control calves were not significantly influenced by the weaning, but in experimental calves were higher before weaning and by 1st d following the weaning as compared to control group (P<0.05). Plasma cortisol levels declined significantly by 4th and 9th d following the weaning as compared to the preweaning levels.
Plasma glucose levels in control calves did not change significantly throughout the experiment. Glucose levels in experimental calves increased significantly by 4 and 9 d following the weaning as compared to the preweaning level. Plasma cholesterol levels in experimental calves, declined significantly by 4th and 9th d as compared to the preweaning levels.
Plasma urea levels following weaning declined significantly in experimental calves, while in control calves urea levels were not significantly changed as compared to the preweaning levels. Plasma indol levels in experimental calves were significantly lower by 1st and 4th day following weaning relative to control group.