An evaluation of endo-beta-D-mannanase (Hemicell) effects on broiler performance and energy use in diets varying in beta-mannan content.
Two experiments were conducted to evaluate the effects of a commercial endo-beta-D-mannanase (Hemicell) on overall performance, MEn, net energy for gain, and some serum parameters of broilers fed diets varying in beta-mannan level (experiment 1) and to evaluate effects of enzyme level on the same variables in broilers fed diet high in beta-mannan (experiment 2). As a semipurified beta-mannan source, guar gum was used to alter the dietary beta-mannan level. In experiment 1, guar gum was added at 0, 0.5, 1, and 2% in a corn-soy-based starter diet with (0.05%) and without endo-beta-D-mannanase supplementation in a 4 x 2 factorial design. Enzyme supplementation improved (P < 0.01) feed efficiency at control and each guar gum inclusion level, whereas 2% guar gum supplementation reduced (P < 0.01) BW and increased (P < 0.01) 14-d feed:gain ratio. Enzyme supplementation also increased dietary MEn and net energy gain. In experiment 2, endo-beta-D-mannanase was added at 0, 0.5, 1, and 1.5% in a corn-soy-based starter diet containing 1% guar gum. Increasing endo-beta-D-mannanase supplementation did not affect (P > 0.10) final BW but improved 14-d feed:gain ratio at all inclusion levels. As in the first experiment, ME improved (P < 0.05) with increasing enzyme inclusion. Dietary endo-beta-D-mannanase inclusion significantly reduced water:feed ratio and total dry fecal output (P < 0.01). Taken together, the results of these 2 experiments indicate that endo-beta-D-mannanase supplementation may improve the utilization of nutrients in diets containing beta-mannan.
Daskiran
M
M
Department of Animal Science, Oklahoma State University, Stillwater, Oklahoma 74078, USA.
Teeter
R G
RG
Fodge
D
D
Hsiao
H Y
HY
D000821:Animal Feed; D000818:Animals; D002645:Chickens / Q000254:growth & development*; D019587:Dietary Supplements; D004734:Energy Metabolism / Q000187:drug effects*; D005685:Galactans; D008351:Mannans / Q000378:metabolism*; D008361:Mannosidases / Q000378:metabolism / Q000494:pharmacology*; D053149:Plant Gums
D005685:Galactans; D008351:Mannans; D053149:Plant Gums; C007894:guar gum; D008361:Mannosidases; C041867:endo-1,4-beta-D-mannanase