The Influence of the Thiamine Intake of the Pig on the Thiamine Content of Pork with Observations on the Riboflavin Content of Pork

Abstract

Three lots of pigs were fed rations containing 5716, 3447 and 1318 μg. of thiamine per pound of feed, respectively. The average feed consumption was approximately the same for the three lots of pigs. Thus, the average daily thiamine intakes were approximately 29, 17 and 7 mg., respectively. Results with respect to growth and feed consumption were similar for the three lots of pigs in spite of the differences in thiamine intake. Thiamine values were determined on pork samples taken from the shoulder, the middle of the loin, the ham end of the loin and the liver. An increase of approximately 100% in the thiamine content of pork muscle resulted when the thiamine intake was increased from 1318 to 3447 μg. per pound of feed. A similar increase of the order of 15 to 20% resulted from an increase in the thiamine content of the feed from 3447 to 5761 μg. per pound. The average thiamine values, on the fresh basis, for shoulder, center loin and ham end of loin, at the lower level of thiamine intake, were 7.9, 9.5 and 10.3 μg. per gram, respectively. At the high level of thiamine intake the corresponding values were 17.3, 23.1 and 23.9 μg. per gram. The thiamine content of pork loin was found to be consistently higher than that of pork shoulder. Pork liver, as compared to muscle, was found to be relatively low in thiamine content. There was some increase in the thiamine content of the liver as the result of feeding more thiamine, but the main depository of thiamine in the pig is the muscle tissue. Limited observations with but two pigs seem to indicate that pork muscle tissues have nearly reached the saturation point, so far as thiamine storage is concerned, when the thiamine content of the ration approximates 5800 μg. per pound. As the result of these preliminary observations it is concluded that thiamine accumulation in pork muscle is relatively rapid. These experiments are being continued. Riboflavin values were determined for all of the pork samples. The riboflavin content of pork muscle is low as compared to this tissue's content of thiamine. Pork liver is relatively high in riboflavin content.