| dc.description.abstract | Thirty-two select line and 32 control line pigs (average, 20 kg) were used in each of the two experiments to assess the effect of dietary amino acid restrictions during the grower phase on serum metabolites. In Exp. 1, 16 pens with two gilts and 16 pens with two barrows per pen were assigned within the genetic line to grower diets (6.1 or 11.1 g lysine/kg) and finisher diets (6.1 or 8.9 g lysine/kg) in a 2 x 2 x 2 factorial arrangement of treatments. Similarly, 16 pens with two gilts and 16 pens with two barrows per pen were assigned within the genetic line to grower diets (5.0, 7.0, 9.0, or 11.0 g lysine/kg) in a 2 x 4 factorial arrangement of treatments, and pigs were offered common Finisher 1 and Finisher 2 diets in Exp. 2. Blood samples were collected at the end of the grower and finisher phases, in Exp. 1. Whereas, blood samples were collected at the beginning of the study, at the end of the grower and finisher phases, in Exp. 2. Serum concentrations of
albumin (P = 0.001) at the end of the grower phase and cholesterol (P = 0.029) and albumin (P = 0.001) at the end of the finisher phase were greater in pigs fed the high-amino acid grower diet than those fed the low-amino acid grower diet in Exp. 1. At the end of the finisher phase, triglyceride (P = 0.029), albumin (P = 0.005), and glucose (P = 0.027) concentrations were reduced in pigs fed the high-amino acid finisher diet compared with those fed the low-amino acid finisher diet. The select line pigs had higher concentrations of cholesterol (P = 0.009) at the end of the grower phase and triglyceride (P = 0.036) and albumin (P = 0.016) at the end of the finisher phase than the control line pigs. In Exp. 2, as the amino acid content of the grower diets increased, cholesterol was reduced (linear, P = 0.005; quadratic, P = 0.026; cubic, P = 0.039), but total protein (linear, P = 0.040) and albumin (linear, P = 0.001) concentrations were increased at the end of the grower phase. The select line pigs had greater concentrations of triglyceride (P = 0.001), total protein (P = 0.041), and glucose (P = 0.005) at the end of the grower phase and triglyceride (P = 0.031) and total protein (P = 0.001) at the end of the finisher phase than the control line pigs. Serum cholesterol was correlated negatively with lysine intake (r = -0.38; P = 0.039) during the grower phase and urea N (r = -0.39; P = 0.032) at the end of the grower phase in Exp. 1 and positively with ultrasound backfat (r = 0.78; P = 0.001) at the end of the grower phase in Exp. 2. The results indicated that the metabolite profile can be affected by both early dietary amino acid restrictions and the genotype. By understanding completely the effect of early dietary restrictions and genotypes on metabolite profile, we can contribute greatly to the development of optimum feeding strategies for successful and sustainable pig production. | en_US |
