The effects of steam-pressure treatment, pelleting and ammoniation on the feeding value of sugarcane bagasse for cattle

Abstract

Digestibility, intake and performance trials were conducted with cattle to evaluate the effects of physical and chemical treatments on the nutritive value of sugarcane (Saccharum officinarum) bagasse. The four treatments in the digestibility trial were: 1, untreated raw bagasse; 2, steam-pressure treatment with a continuous flow digester (SP); 3, steam-pressure treatment plus pelleting (SPP); 4, steam-pressure treatment, 3% anhydrous ammonia and pelleting (SPA). Steam-pressure treatment and pelleting, both with and without ammoniation, increased voluntary feed consumption (P < 0.01) by 80% and 36%, respectively. Apparent digestion coefficients for organic matter, crude protein, cellulose, neutral and acid detergent fiber were not affected by steam-pressure treatment, but were reduced (P < 0.05) when this was followed by pelleting. Sixty Brahman crossbred steers (340 kg) were allotted to 12 groups of five animals (three pens per treatment) and fed one of the treatment diets for 100 d. The four treatments were: 1, cottonseed hulls; 2, pelleted raw bagasse; 3, SPP bagasse; 4, SPA bagasse. Average gains (kg d−1) and feed-to-gain ratios for the four diets were as follows: 1, 0.91 and 8.78; 2, 1.10 and 8.39; 3, 1.12 and 7.72; 4, 1.15 and 7.98. Treatment means did not differ (P > 0.05). SPP bagasse was compared with bermudagrass pellets and corn silage in growing diets for cattle. Ninety-six Brahman crossbred steers (167 kg) were allotted to 12 groups of eight animals (four pens per treatment) for 134 d. SPP bagasse pellets depressed gains and feed conversion ratio (P < 0.05). Gains (kg d−1) and feed-to-gain ratio for SPP bagasse pellets, bermudagrass pellets and corn silage diets were 0.42 and 12.90, 1.02 and 7.65, and 0.94 and 5.87, respectively. This investigation demonstrated that feeding pelleted bagasse at 15% of the diet did not reduce performance of finishing cattle fed a high-grain diet. However, when growing cattle were limit-fed a grain-based supplement with free access to bagasse pellets, bermudagrass pellets or corn silage (approximately 70% of the diet), gains and feed efficiency were significantly (P < 0.05) lower on the bagasse diet. Key words: Sugarcane bagasse, steam-pressure treatment, ammonia, digestibility, cattle performance