Effects of Increasing Standardized Ileal Digestible Valine:Lysine Ratios on the Growth Performance of 50 to 80 lb Pigs

Authors

Samantha A. Swanson, Kansas State UniversityFollow
Jason C. Woodworth, Kansas State UniversityFollow
Mike D. Tokach, Kansas State UniversityFollow
Robert D. Goodband, Kansas State UniversityFollow
Joel M. DeRouchey, Kansas State UniversityFollow
Katelyn N. Gaffield, Kansas State UniversityFollow
Jordan T. Gebhardt, Kansas State UniversityFollow

Keywords

amino acid, growing pig, lysine, valine

Abstract

A total of 351 pigs (DNA 600 × 241; initially 47.1 ± 0.77 lb) were used in a 21-d experiment to determine the effects of increasing standardized ileal digestible (SID) Val:Lys ratio in 50 to 80 lb pigs. There were 12 replications per treatment with five pigs per pen. Pens of pigs were randomly assigned to one of six corn-soybean meal-based dietary treatments with SID Val:Lys ratios of 60, 63, 66, 69, 72, and 75%. A basal diet was formulated with the lowest SID Val:Lys ratio and L-valine was added to create the diet with the highest Val:Lys ratio. The high and low diets were then blended to create the intermediate diets. On d 0, 10, and 21, pigs were weighed to determine ADG, ADFI, and F/G. Blood was drawn on d 10 for plasma urea nitrogen (PUN) analysis. From d 0 to 10, BW, ADG and F/G improved (linear, P < 0.05) as SID Val:Lys ratio increased, but with little improvement past a 72% Val:Lys ratio. No differences were observed from d 10 to 20 (P > 0.10). Similar to d 0 to 10, the overall F/G improved (linear, P = 0.012) as Val:Lys ratio increased but with little improvement past 72% Val:Lys ratio. As Val:Lys ratio increased, there was an increase in PUN concentration (linear, P = 0.029). Valine intake grams per day and Val intake per kg of gain increased (linear, P < 0.001) as Val:Lys ratio increased. Lysine intake per kg of gain decreased (linear P = 0.029) as the Val:Lys ratio increased. Broken-line analysis indicated overall feed efficiency improved with increasing Val:Lys ratio with the breakpoint at a 69% SID Val:Lys ratio. The results of this study suggest that a 69 to 72% SID Val:Lys ratio may be ideal for 50 to 80 lb pigs.

Recommended Citation

Swanson, Samantha A.; Woodworth, Jason C.; Tokach, Mike D.; Goodband, Robert D.; DeRouchey, Joel M.; Gaffield, Katelyn N.; and Gebhardt, Jordan T. (2025) "Effects of Increasing Standardized Ileal Digestible Valine:Lysine Ratios on the Growth Performance of 50 to 80 lb Pigs," Kansas Agricultural Experiment Station Research Reports: Vol. 11: Iss. 7. https://doi.org/10.4148/2378-5977.8766