Effect of Recombinant Porcine SomatotroDin and Dietary Protein Enzymes

This study was conducted to determine the effect of daily recombinant porcine somatotropin (rpST) injection (0 or 120 pg/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 amy1ase:protein and amy1ase: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 1 4 O/O 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.