Age-related changes in the concentrations of serum proteins in calves

The objective of this study was to describe the physiological differences in serum protein electrophoretic pattern in calves at different ages and nutrition. One hundred and one clinically healthy calves at the age from 2 weeks till 6 months were included into the study. On the basis of their age and age-related feeding management, the calves were divided into five groups (calves at the age of 2 weeks, 1 month, 2, 3-4, and 5-6 months). Blood samples were taken by direct puncture of v. jugularis. Blood serum was analyzed for total serum protein concentrations, the relative and absolute values of protein fractions (albumin, alpha(1) [alpha(1)]-, alpha(2) [alpha(2)]-, beta(1) [beta(1)]-, beta(2) [beta(2)]-, and gamma [gamma]-globulins) with calculation of albumin: globulin ratios. The results showed a significant effect of age and changes in nutrition on the serum total protein (TP) concentrations and the most of protein fractions. Significantly higher relative concentrations of albumin, alpha-globulins (predominantly alpha(2)), as well as beta(1)-globulins were found in younger calves compared with older animals (P < 0.001, P < 0.001, and P < 0.001, respectively). On the other hand, the relative values of beta(2)-, gamma-globulins, and TPs were significantly lower in younger calves than in older ones (P < 0.05, P < 0.001, and P < 0.001, respectively). Therefore, it is essential to determine the physiological serum protein electrophoretic pattern in different age groups of calves, because these reflect the physiological response of animals to changes in nutrition, growth or development. Our results suggest that the age of animals should be taken into consideration when interpreting the serum protein profile.