INTESTINAL ABSORPTION OF CYANOCOBALAMIN IN SOWS AS INFLUENCED BY SIZE OF ORAL DOSE, PREGNANCY, AND LACTATION

Abstract

Two experiments were conducted to study Co60-cyanocobalamin absorption by means of the fecal excretion method. In the first experiment, eight 1.5-year-old non-pregnant sows were used at seven intragastric dosage levels: 10, 25, 50, 100, 200, 400, and 800 μg. Each animal was tested at each dosage level. Absorption increased significantly between the 10- and 50-μg doses. There were significant between-sow differences in absorption at the 100-μg level and evidence of increased absorption in some sows at doses of 100 and 200 μg. The data suggest that there is an upper limit to the quantity absorbed, that this limit varies in magnitude from one sow to another, and that it is reached at different dosage levels. The nutritional significance is discussed.The second experiment investigated the effects of pregnancy and lactation on absorption in eleven 2.5-year-old sows. Absorption from 50-μg doses increased between the last week of gestation and the second week of lactation, and decreased by the end of the first week after lactation. Low absorption in three sows was associated with poor reproduction.