Vitamin Supplementation Rates for U.S. Commercial Broilers, Turkeys, and Layers

Actual vitamin fortification rates were determined for U.S. commercial broiler, turkey, and egg layer feeds. Over 90% of each respective industry was represented. With few exceptions, commercial vitamin fortification rates exceeded National Research Council (NRC) recommendations. Mean vitamin fortification rates of Starter diets were higher than those for Finisher diets, and breeder diets were more heavily supplemented than Starter diets. Coefficients of variation for supplementation rates generally were high, but were lower in Starter than in Finisher diets. Rates for fat soluble vitamins were less variable than water soluble vitamins. As a proportion of either vitamin A or D, vitamin E supplementation remained essentially unchanged for broilers in all growth periods, whereas for turkeys, vitamin E fortification decreased by one-fourth from Starter to Finisher.