Biotin bioavailability from protein supplements and cereal grains for growing broiler chickens.

A 21d growth bioassay was conducted with broiler chicks to estimate the availability of biotin from canola meal (CM), cereal grains and CM-supplemented cereal diets. A standard biotin response curve was generated with biotin-supplemented diets, using growth rate (g/d) as the dependent variable (X) and biotin intake (micrograms/d) as the independent variable (Y), as follows: Y = 2.28X + 9.76, r = 0.946 (P less than 0.01). Other groups of chicks were fed diets containing CM, soybean meal (SBM), cereal grains or CM + grain as a source of biotin. Results indicated that biotin bioavailability (%) was low in most cereal grains, i.e. wheat 17, triticale 20, barley 21, and sorghum 39; moderate in CM, 66; and high in SBM, 98, and maize, 114. Plasma and liver biotin concentrations in excess of 4000 ng/L and 3000 ng/g, respectively, were indicative of adequate biotin status.