Investigating the amino acid digestibility of alternative protein sources and determining the impact of dietary fiber on energy, nitrogen, and amino acid digestibility in growing pigs

Cotten, Bradley M. M.S., Purdue University, May 2015. Investigating the amino acid digestibility of alternative protein sources and determining the impact of dietary fiber on energy, nitrogen, and amino acid digestibility in growing pigs. Major Professor: Olayiwola Adeola. Three experiments were designed to quantify the nitrogen (N) and amino acid (AA) digestibility of various protein sources fed to growing pigs. The protein ingredients were sunflower meal, cottonseed meal, canola meal, camelina meal, egg albumen, casein, blood meal, plasma meal, potato protein concentrate, soy protein concentrate, soy protein isolate, and linseed meal, which were fed as the sole source of amino acids for the animals and were included in semi-purified, corn starch-based diets. A semipurified, nitrogen-free diet (NFD) was used to estimate endogenous losses of AA. In each experiment, pigs were surgically fitted with a simple T-cannula at the distal ileum and fed four experimental diets and the NFD based on a 5 X 2 crossover arrangement in a randomized crossover design, with 5 diets and 2 periods. For experiment 1 (Exp. 1), sunflower meal, cottonseed meal, canola meal, and camelina meal were fed to 19, 42-kg barrows to determine the apparent (AID) and standardized (AID) digestibility of AA at the terminal ileum. The AID and SID of N and all AA were greatest for sunflower meal (P < 0.05), and canola meal had similar AID and SID of N, Met, Thr, Leu, and Val. The AID and SID of all essential AA, except for Met and Trp, was lower in camelina meal