Indicators of passive immunity and health status of calves

The aim of this study was the determination of immunoglobulin (IgG, IgM, IgA), total serum protein content and activity of enzyme GGT in sera of 71 dairy calves up to the age of four weeks. We investigated to which extent the sera profiles correlated with total immunoglobulin level in the administered colostrum. The results were related to the health status of the calves. One of the goals of the study was also to asses the applicability of these indicators of colostrum supplied in Slovenian herds. In the serum samples the concentration of IgG, IgA, IgM, TSP and activity of GGT were measured. In colostrum samples the total Ig level was estimated. The correlations between the colostral Ig content and the concentration of IgG, TSP and activity of GGT were significant up to the 4th week of age. Only on the base of the values of the investigated parameters no direct conclusion about the foreseen health status of calves is possible. The investigated indicators are suitable to assess colostrum supply in calves at least up to the 3rd week of age. Indirect indicators such as TSP and GGT are more reliable to ascertain if the colostrum was absorbed as for estimation of immunoglobulin levels in the calf's serum.