Author : Dustin Clay Kendall
Publisher :
ISBN 13 :
Total Pages : 312 pages
Book Rating : 4.:/5 (616 download)
Book Synopsis Opportunities and Limitations for Low-protein Diet Formulation in Swine by : Dustin Clay Kendall
Download or read book Opportunities and Limitations for Low-protein Diet Formulation in Swine written by Dustin Clay Kendall and published by . This book was released on 2004 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental pressure is forcing the swine industry to evaluate technologies that reduce nitrogen excretion. Among the available techniques, manipulation of dietary protein has shown improvement in the nutrient balance of swine farms. This is accomplished by replacing a portion of intact protein sources with crystalline amino acids. Dietary amino acid concentrations are maintained while lowering total nitrogen intake, therefore reducing nitrogen excretion but preserving growth performance. Based on this knowledge, pork producers seek information on the maximum levels of crystalline amino acids that can be added to diets of growing pigs. This dissertation will investigate the nutritional constraints to high crystalline amino acid supplementation and validate their use under commercial conditions. The following experiments provide estimates of optimum lysine, tryptophan, isoleucine, valine, and nonessential amino acid levels in diets for growing pigs. A series of experiments (3,628 pigs) evaluated optimum lysine levels during the nursery phase (11 to 27 kg) under commercial conditions. Pigs were offered diets with constant inclusion of soybean meal, where dietary lysine was titrated with the addition of crystalline lysine. In order to maintain optimum amino acid ratios, crystalline methionine, threonine, tryptophan, isoleucine, and valine were added as necessary. The results showed optimum lysine levels in the nursery of 1.33% true ileal digestible (TID) lysine, indicating that previous lysine requirement estimates have been grossly underestimated. Once the lysine requirement is established, it is possible to evaluate optimal ratios of other amino acids relative to lysine. Three experiments investigated optimum TID tryptophan to lysine ratio in late finishing barrows (90 to 120 kg). Results indicate that TID tryptophan to lysine levels of 0.15 can be used without affecting growth performance. Three experiments evaluated optimum TID valine to lysine ratio in 13 to 32 kg barrows. The data showed an optimum TID valine to lysine ratio of 0.65. Three additional experiments assessed TID isoleucine to lysine requirements of 90 to 120 kg barrows, utilizing corn-blood cell diets. Blood cells possess high levels of leucine and valine, but are severely deficient in isoleucine, a key characteristic in basal diet formulation for isoleucine requirement studies.
