EFFECT OF RECOMBINANT PORCINE SOMATOTROPIN AND DIETARY-PROTEIN ON PANCREATIC DIGESTIVE ENZYMES IN THE PIG

This study was conducted to determine the effect of daily recombinant porcine somatotropin [rpST] injection [0 or 120-mu-g/kg BW] and dietary CP level of the feed [14 or 26% CP] on pancreatic characteristics of growing pigs. Daily injection of rpST did not affect pancreatic weight [P = .885] but did decrease pancreatic amylase content [P = .005]. The ratios of amylase:protein and amylase:trypsin were also lowered by daily rpST injection [P = .002 and P = .0002, respectively]. There were protein x rpST and protein x rpST x sex interactions for the ratio of amylase: chymotrypsin. The CP content of the diet had a greater effect than the injection of rpST on pancreatic characteristics. Pigs consuming the 26% CP diet had significantly higher pancreatic weight [P = .003] and greater total pancreatic chymotrypsin [P = .006] than pigs consuming the 14% CP diet. The ratios of trypsin and chymotrypsin to DNA were also higher in pigs fed the 26% CP diet [P = .007 and P = .005, respectively]. These responses were not influenced by sex. Recombinant porcine somatotropin seemed to have a slight effect on porcine pancreatic characteristics; however, dietary protein had a greater effect on pancreatic characteristics in market-weight hogs.