Effect of Colostral Immunoglobulin G1 and Immunoglobulin M Concentrations on Immunoglobulin Absorption in Calves

Abstract

Twenty-three calves were fed colostrum at 110 ml/kg body wt divided into 2 feedlings at 1 and 13 h of age. The concentrations of Ig were measured in the colostrum fed and in the calves'' sera following colostrum feeding. Apparent efficiency of Ig absorption was calculated for each calf. Significant negative correlations between efficiency of absorption and mass of Ig fed were observed for both Ig. A separate group of 225 calves born on a commercial dairy were fed 2.84 l of colostrum by 4 h of age. Concentrations of IgG1 in the colostrum fed and in the calves'' sera at 48 h were measured. Negative correlation was observed between the efficiency of absorption and the mass of IgG1 fed. These results suggest a physiologic limitation to the mass of Ig that can be absorbed to serum from a given volume of colostrum. No indication of a selective Ig absorption mechanism was observed.