AN INVESTIGATION OF IMMUNIZATION AGAINST SOMATOSTATIN BY MEASURING GROWTH AND CARCASS PARAMETERS IN GILTS

To investigate the effects of immunization against somatostatin (SRIF) on growth rate, feed efficiency and carcass quality; forth-eight Yorkshire gilts ($age=37.5{\pm}4.3d,\;wt=8.2{\pm}1.6kg$) were randomly assigned to one of the following three treatments (1) control, (2) bovine serum albumin (BSA) and (3) SRIF. Cyclic SRIF was conjugated to BSA as the antigen containing 1 mg of SRIF diluted in 3 ml of saline. The conjugate was injected subsutaneously together with bacterial cell protein (BP) adjuvant on both sides of the neck of each gilt as the initial injection with three subsequent booster injections. Throughout the experiment all pigs were fed ad libitum a corn-soy diet containing 20% protein. Body weight and feed intake were measured on a weekly basis. All pigs in the experiment were slaughtered when they approached 101 kg body weight on the weekly weigh day. After slaughter, carcass parameters were analyzed to assess carcass quality. Results revealed that there were no differences among SRIF, BSA and control treatments for average daily gain, feed efficiency and feed intake during the first 5 wk of the experiment and from 6 wk to slaughter. The results for carcass analysis indicated that active immunization against SRIF had no effect on fat content, lean yield, water content and Canadian carcass index These data, collectively, suggest that the protocol employed in the present investigation for active immunization against SRIF is not an effective method for the enhancement of pig growth and improvement of feed efficiency and carcass quality.