The absorption of 131 I-labelled serum and colostral proteins from the gut of the young calf

Abstract

The absorption of 131 I-labelled adult bovine serum and colostral proteins by the gut of the newborn calf has been studied by means of tracer and electrophoretic techniques. The several proteins present in the labelled serum and colostrum appeared to be absorbed with equal facility; there was no evidence that the calf gut showed any selectivity in the absorption of proteins such as is known to occur in the young rat. Electrophoretic separation and measurements of radioactivity of calf serum taken 3, 6 and 20 h after feeding with labelled whole serum indicated that the serum albumin and β -globulin left the circulation at a rate greater than that of the γ -globulins. Three hours after feeding 8 to 16% of the labelled proteins were estimated to be circulating in the plasma. At 20 h 5 to 10% were estimated to be present in the circulation.