Effect of potassium isobutyrate on absorption of immunoglobulins from colostrum by calves.

Calves received either colostrum with 2.83 meq potassium isobutyrate per gram of gamma-globulin or colostrum with distilled water within 1 h after birth. Blood samples were taken at intervals during the first 72 h for determination of concentrations of gamma-globulin, immunoglobulin IgG and IgM. Calves fed colostrum with distilled water attained higher concentrations in serum of total gamma-globulin, immunolgobulin IgG and IgM. Holstein calves were more efficient than Ayrshire calves in absorbing total gamma-globulin, but differences between breeds were not significant for specific immunoglobulins. Efficiency of gamma-globulin absorption within 24 h was 35.7% for control calves and 24.7% for calves fed colostrum plus potassium isobutyrate. Potassium isobutyrate had a depressing effect on absorption of immunoglobulins by calves.