|DE Lange, Cornelis -|
|Levesque, Crystal -|
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: February 1, 2013
Publication Date: April 1, 2013
Citation: De Lange, C., Levesque, C., Kerr, B.J. 2013. Amino acid nutrition and feed efficiency. In Patience, J.F., editor. Feed Efficiency. The Netherlands: Wageningen Academic Publishers. p. 81-100. Technical Abstract: In growing pigs, whole body protein deposition (PD) is the main determinant of dietary amino acid requirements and is closely associated with lean tissue growth, feed efficiency, and carcass quality. In North America, the typical mean PD for barrows and gilts between 25 and 125 kg body weight is approximately 135 g/d, but PD is known to be highly variable between and within groups of pigs. The use of dietary amino acids for PD involves digestion, absorption, and post-absorptive metabolism; biological processes which are all influenced by factors associated with the animal (pig genotype, physiological state and health status) and the environment (diet composition, thermal and physical environment) and should be considered when establishing optimum dietary amino acid level for groups of pigs. Mathematical models, such as the NRC (2012), are now available in which the biology of dietary amino acid utilization for PD is represented, which can be used to estimate amino acid requirements of groups of pigs maintained in a relatively stress and disease-free environment. For predicting amino acid requirements of groups of pigs, between-animal variation in growth performance and nutrient utilization should also be taken into account. In addition, nutritional history and compensatory growth should be considered when establishing optimum dietary amino acid levels for maximum profit. Some examples are provided in this chapter to illustrate the effect of gender and feeding high-fiber co-products on amino acid requirements of growing-finishing pigs.