The Effect of Age and Supplemental Amino Acids on the Utilization of Milk and Soya Protein by the Young Pig

Digestion in the pig between 7 and 35 d of age 6. The digestion of hydrolyzed milk and soya-bean proteins

“…Soya-bean proteins have been extensively given to pigs of all ages, but with pigs of 14 d of age or less their performance has always been lower than that of pigs given diets containing milk proteins (Hays et al 1959;Maner et al 1961 ;Wilson & Leibholz, 1981 a). Wilson & Leibholz (1981 c) showed that there was a greater hydrolysis of milk proteins in the small intestine of the 28-d-old pig than that of soya-bean proteins.…”

“…Hydrolysis of proteins before feeding resulted in a reduced trypsin and chymotrypsin activity in the 12. Retention of dietary N i.1 the carcass was greater in pigs given the milk-protein diets (0.79) than in those the ISP diets and 0.86 and 0.97 for the pigs given the milk-protein diets.1089 min.the pigs given the intact-and hydrolyzed-protein diets.containing hydrolyzed proteins than in those given diets containing the intact proteins.ISP diets than when they were given the milk-protein diets.duodenum and pancreas.given the ISP diets (0.68).Numerous experiments (Hays et al 1959;Maner et al 1961 ;Wilson & Leibholz, 1981 a) have shown that the performance of pigs given soya-bean meal, soya-bean flour or isolated soya-bean protein (ISP) was inferior to that of pigs given milk proteins between 7-28 d of age. The young pig has ii limited capacity to secrete pepsin and acid, and this increases with age (Cranwell, 1977) arid the proteinase activity of the pancreas also increases with age (Coring et al 1978).…”

“…Numerous experiments (Hays et al 1959;Maner et al 1961 ; Wilson & Leibholz, 1981 a) have shown that the performance of pigs given soya-bean meal, soya-bean flour or isolated soya-bean protein (ISP) was inferior to that of pigs given milk proteins between 7-28 d of age. The young pig has ii limited capacity to secrete pepsin and acid, and this increases with age (Cranwell, 1977) arid the proteinase activity of the pancreas also increases with age (Coring et al 1978).…”

Blood plasma free amino acid studies in swine

“…Both curves intercede at the four to five weeks period, which would somewhat be expected on the basis of the data reported by Lewis et _al. (1955) and Hays (1957) and the present blood data of this experiment.…”

Relationship of blood plasma free amino acids and ingested protein in swine

“…Previous published data have shown that methionine addition to soybean protein has repeatedly improved body gain and feed efficiency (Acker et al, 1959;Hays et al, 1959). When methionine and valine were added to the basal ration, pig gains were depressed slightly as compared to pigs fed the basal ration.…”