Abstract

PICHARDO, Adrián et al. Limiting amino acids in wheat for growing-finishing pigs. INCI [online]. 2003, vol.28, n.5, pp.287-291. ISSN 0378-1844.

Four experiments involving 136 crossbred (Landrace-Hampshire-Duroc) pigs were conducted to determine the order of the first three limiting amino acids (LAA) in wheat for growing and finishing pigs. Treatments consisted in additions of lysine, threonine and/or methionine to adjusted basal and control diets. In Exp. 1, lysine increased daily gain (ADG), intake of feed (FI), lysine (LI), threonine (TI) and methionine (MI), and improved feed conversion (F/G). Additional threonine increased ADG and TI, and improved F/G. Methionine increased MI, but did not affect ADG or F/G. In Exp. 2, threonine increased ADG and TI, and improved F/G. Inclusion of methionine tended to decrease ADG and depressed F/G. Pigs fed lysine-threonine added and control diets showed no differences in ADG, FI or F/G, although control fed pigs had higher TI and MI. In Exp. 3, threonine alone did not affect ADG or F/G, but combined with methionine increased ADG and improved FG. There were no differences in ADG and F/G between control or lysine-threonine added diets. In Exp. 4, threonine tended to increase ADG and improved F/G while methionine reduced ADG. Addition of threonine plus methionine increased ADG, but did not affect FI or F/G. These data indicate that, in wheat, lysine and threonine are the first and second LAA for growing and finishing pigs. Methionine alone does not limit growth in pigs fed wheat-based diets, but appears to enhance the threonine response in finishing pigs. Lysine and threonine can replace soybean meal in wheat-based diets for growing-finishing pigs.

Keywords : Limiting Amino Acids ; Pig Feed / ; Wheat .