COMPARISON OF THE SLAUGHTER METHOD AND SIMPLE T-PIECE CANNULATION OF THE TERMINAL ILEUM FOR DETERMINING ILEAL AMINO-ACID DIGESTIBILITY IN MEAT AND BONE MEAL FOR THE GROWING PIG

The study aimed to evaluate the slaughter technique for sampling ileal digesta in the pig under defined sampling conditions. Comparisons of apparent ileal amino acid digestibility in meat and bone meal (MBM) were made between eight pigs whose digesta were sampled from the terminal 20 cm of ileum at death (barbiturate), 9 h after the commencement of feeding, and eight pigs with recently implanted simple T-cannulas and with hourly collection of digesta over 1 0 h on the final 2 days of the 14 day study. The sampling procedure for the slaughtered animals was found to be optimal in a preliminary investigation. The simple T-cannulated animals were accepted as the control. Chromic oxide was included in the diet as an indigestible marker. There was no significant (P > 0.05) effect of digesta collection procedure on the apparent ileal nitrogen (N) or amino acid digestibility coefficients. Nor were the digestibility data more variable with the slaughter method. Faecal N and amino acid digestibility coefficients obtained with the intact pigs were similar to those in pigs fitted with a simple T-piece cannula in the distal ileum. However, faecal digestibility values in both intact and cannulated pigs were considerably higher (P < 0.05) than the corresponding ileal values. The slaughter technique is a viable alternative to simple T-cannulation for the determination of N and amino acid digestibility in the pig given a semisynthetic MBM-based diet.