Date of Award
Doctor of Philosophy
D. R. Zimmerman
Two experiments were conducted to study the use of [superscript]13C abundance to partition ileal digesta protein into undigested feed and endogenous portions. In both experiments, pigs were fed diets consisting of corn-corn gluten meal-crystalline amino acids or wheat-soybean meal during a growing phase. The corn-corn gluten meal diets contained feedstuffs from C[subscript]4 plants and the wheat-soybean meal diets contained feedstuffs from C[subscript]3 plants. C[subscript]4 plants have delta [superscript]13C values of -13.5 ± 1.5\perthous and C[subscript]3 plants have delta [superscript]13C values of -28.1 ± 2.5\perthous. Three pigs/treatment group were killed when treatment groups averaged 10.5, 22.9 and 46.6 kg (Experiment 1) and on d 0, 4, 7, 14 and 28 (Experiment 2). Protein fraction (Experiment 1) or lysine (Experiment 2) of M. Longissimus (Experiment 1 only), empty body, liver and small intestine were analyzed for [superscript]13C abunDance; Each tissue was labeled according to the treatment diet (P <.006) and all tissues, except liver in Experiment 2, had treatment x time labeling (P <.05). In each experiment, 10 pigs averaging 55.0 kg (Experiment 1) and 57.7 kg (Experiment 2) were assigned to metabolism cages and implanted with ileal cannulae (Experiment 1) or ileal cannulae and jugular catheters (Experiment 2). Pigs were fed the same diet type as during the growing phase (C[subscript]4 or C[subscript]3) and then switched to the other diet type for digesta collection. Pigs fed similarly from each treatment group were killed and phe [superscript]13C abundance of the small intestine was used as a label of endogenous amino acid losses. True and apparent amino acid digestibility values (%) for the corn-corn gluten meal diets were, respectively: Lys 85.8, 81.5; Thr 76.2, 66.7; Ile 91.3, 88.2; Phe 89.9, 86.5. True and apparent amino digestibility values (%) for the wheat-soybean meal diet were, respectively: Lys 82.6, 73.7; Thr 83.1, 70.6; Ile 87.9, 81.6; Phe 88.3, 82.4. True and apparent amino acid digestibility values (%) for corn were, respectively: Lys 62.2, 46.6; Thr 63.2, 40.2; Ile 70.4, 56.1; Phe 81.9, 72.4. True and apparent amino acid digestibility values (%) for wheat were, respectively: Lys 88.6, 61.1; Thr 88.9, 59.1; Ile 86.1, 70.7; Phe 88.6, 77.4. True and apparent amino digestibility values (%) for soybean meal were, respectively: Lys 95.8, 88.4; Thr 99.2.7, 81.5; Ile 95.7, 86.5; Phe 96.7, 88.8. Crystalline lysine had true and apparent digestibility values of 95.8% and 92.9%.
Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/
Roger Alan Arentson
Arentson, Roger Alan, "True digestibilities of amino acids and protein in pigs using 13C as a label to determine endogenous amino acid excretion " (1993). Retrospective Theses and Dissertations. 10793.