Enhanced incidence of leg abnormalities in reovirus WVU 2937-infected chickens fed various dietary levels of selected vitamins.

Five experiments were conducted to evaluate the incidence of leg abnormalities of 4-, 6-, and 8-week-old reovirus WVU 2937-infected and uninfected chickens fed diets containing 20%, 100%, or 200% of the 1977 National Research Council nutrient requirements (NRC-77) of poultry for manganese, biotin, niacin, choline, or folic acid. Reovirus infection significantly elevated the incidence of leg abnormalities in the biotin-, niacin-, and folic-acid-deficient chickens and decreased the incidence of leg abnormalities in choline-deficient chickens. Reovirus-infected male chickens had a significantly greater incidence of leg abnormalities than reovirus-infected female chickens in the biotin, niacin, and folic acid studies. No sex differences in the incidence of leg abnormalities were observed in uninfected chickens. The incidence of leg abnormalities decreased with increasing dietary levels of biotin, niacin, choline, or folic acid in all chickens except reovirus-infected male chickens in the biotin study. In the manganese study, neither reovirus infection nor dietary level had any effect on the incidence of leg abnormalities in male or female chickens.