BISON AND HEREFORD STEER DIGESTION OF SEDGE HAY

Abstract

The digestibility of sedge hay was measured in six bison (Bison bison) steers and six Hereford (Bos taurus) steers in two total fecal collection trials. The digestion coefficients of all nutrients, except lignin, were significantly greater (P < 0.05) in bison than in cattle. For bison and cattle, respectively, overall mean apparent digestibility coefficients, expressed as a percent, were: dry matter, 51.3 and 46.0; crude protein, 38.3 and 27.6; crude fat, 64.2 and 54.4; neutral detergent fiber, 54.7 and 50.0; acid detergent fiber, 47.0 and 42.4; hemicellulose, 67.1 and 61.7; lignin, 25.2 and 18.7; and gross energy, 50.6 and 45.3. Acid-insoluble ash and lignin were not suitable internal indicators for making species comparisons of digestibilities because of the greater apparent digestion of the indicators by bison. During the summer fecal collection trial, mean daily dry matter intakes of bison and cattle were 1.6% and 1.4% of body weight, respectively. During the winter trial, the mean daily dry matter intake of cattle (2.0% of body weight) was greater (P < 0.05) than that of bison (1.6% of body weight). There was no difference (P > 0.05) between bison and cattle in particle size of feed consumed. Greater forage digestibility resulted in greater (P < 0.05) average daily gain in bison only in the summer trial, when nutrient consumption by cattle was below the published maintenance requirement of the cattle.