EFFICACY OF METHANE FERMENTER RESIDUE AS A SOURCE OF ROUGHAGE FOR CATTLE FED GRAIN BASED DIETS

Cattle manure was used as substrate for a methane fermentor and the re sidue was investigated as a source of roughage ingrain- based feedlot cattle diets. Eighty-eight steers (initial weight, 326 kg) were allott ed by weight to 15 pens for a 113 day trial. Dietary treatments were: 1) 85% concentrate + 15% com silage (control), 2) 95% concentrate + 5% methane fermentor residue, 3) 92.5% concentrate + 7.5% methane fermen tor residue, 4) 90% concentrate + 10% methane fermentor residue, and 5 ) 875% concentrate + 12.5% methane fermentor residue. The concentrate was based primarily of whole shelled com. Daily gains of steers fed th e control diet (15% com silage) were greater (P<0.05) than those of st eers fed the 5% methane fermentor diet but did not differ (P>0.10) fro m steers fed the 7.5, 10 and 12.5% methane fermentor diets. Diet did n ot affect (P>0.10) feed intake or carcass characteristics. Digestibili ty of dry matter and organic matter did not differ (P>0.10) between th e control diet and diets containing methane fermentor residue. It was concluded that com silage and methane fermentor residue have equal eff icacy as a source of roughage within the dietary levels tested in this experiment.