Valine nutrient recommendations for Ross x Ross 308 broilers.

Studies delineating the dietary Val needs of modern commercial broilers are sparse. Three studies were conducted to determine the dietary Val nutrient needs of Ross x Ross 308 male broilers. Three time periods were evaluated independently, 0 to 14 d (starter), 14 to 28 d (grower), and 28 to 42 d (finisher) of age. Corn- and peanut meal-based diets for each feeding phase served to titrate the Val dose-response levels. Dietary Val (total basis) was supplied from 0.75% up to 1.15% in 0.08% increments for the starter phase; from 0.73% up to 1.08% in 0.07% increments for the grower phase; and from 0.64% up to 0.99% in 0.07% increments for the finisher phase. Regression analysis was used to calculate the Val nutrient recommendations. These estimates were 1.00% for the starter, 0.95% for the grower, and 0.85% total Val for the finisher period. Dietary Val data obtained for all the feeding periods evaluated exhibited the expected decline with age, characteristic of all amino acids and most nutrients. Total dietary Val needs of 1.00, 0.95, and 0.85% for the starter, grower, and finisher phase, respectively, should provide nutritionists with a guide for nutrient minimums, particularly for their use in Ross x Ross 308 broilers. These values translate into calculated true digestible Val needs of 0.91, 0.86, and 0.78% for the starter, grower, and finisher feeding phases, respectively.