Replacing corn by cassava bagasse in concentrate mix fed to growing cattle. 2. Apparent digestibility, digestible nutrients intake, live weight gain and feed:gain ratio

[摘要] - The objective of this study was to evaluate the effect of the substitution of corn by cassava bagasse in concentrate on apparent digestibility, digestible nutrient intakes, average daily gain (ADG) and feed:gain ratio (F:G) in growing cattle. Sixteen cossbred bulls, were allotted to a completely randomized block design and in two periods. Four types of concentrade were tested, in association with an ad libitum allowance of oat/ryegrass hay (Avena strigosa, L.; Lolium multiflorum, L.) and an average concentrate suplemetation of .83% LW. The concentrates fed to the animals were different by the substitution level of corn by cassava bagasse: T1 0,0; T2, 33,0; T3, 66,0; e T4, 99,0. There was no effect of the substitution of corn by cassava bagasse on the apparent digestibility coefficients of the studied nutritive fractions. The digestible acid detergent fiber intake (DADF) linearly increased with the substitution of corn by cassava bagasse. There was no effect of the treatments on the intakes of digestible dry matter (DDM), digestible organic matter (DOM), digestible neutral detergent fiber (NDF), digestible energy (DE) and metabolizable energy (ME), which were, respectively, for T1, T2, T3 and T4, 53.51; 54.50; 53.63 and 53.69 (g DDM kg0.75·day), 51.77; 52.37; 51.27 and 51.23 (g DOM/ kg0.75·day, 30.13; 30.93; 30.46 and 30.88 (g DNDF/ kg.75·day), 224.13; 228.51; 224.77 and 225.33 (kcal DE/ kg.75·day), 183,75; 287,56; 184,38 and 184,43 (kcal ME/ kg.75·day). The results obtained for ADG were 1.10; 0.95; 1.12 and 0.75 kg/animal·day, and for F:G 4.61; 6.17, 4.58 and 7.98, respectively for T1, T2, T3 and T4. The values of ADG and F:G, for the substitution of 99% of corn by cassava bagasse in concentrate, were lower than those obtained by the levels of 0 and 66%, however, they were similar to the 33% of substitution level of corn by cassava bagasse in the concentrate.

[学科分类] 兽医学

[关键词] cassava bagasse;cattle;intake;feed:gain ratio;digestibility;weight gain;by-product     IntroduçãoBovinos alimentados com dieta de baixa qualidade nem sempre consomem o nível de energia necessário para a síntese de proteína bacteriana