Silage and hay of Stylosanthes Campo Grande associated or not to corn silage: nutrient intake and performance of beef cattle
The conservation of stylosanthes Campo Grande as silage or hay is an alternative to the use of corn as it increases the crude protein level of the diet and improves the soil fertility by nitrogen fixation. The nutrient intake and animal performance of Nellore cattle fed diets containing different roughage sources were evaluated. Experimental treatments were: T1 – corn silage (CS); T2 – silage of stylosanthes Campo Grande (StS); hay of stylosanthes Campo Grande (StH); T4 – 50% of CS + 50% of StS; T5 – 50% of CS + 50% of StH. Diets were isonitrogenous (12.5% of CP on DM basis) and consisted of 50:50 roughage:concentrate ratio. A total of 40 non-castrated cattle with initial average body weight of 360 kg were assigned into a completely randomized design with five treatments and eigth replicates per treatment. The experiment was divided into four periods with a 15 days of adaptation followed by three periods of 28 days each totalizing 99 days of experimental period. Means was compared by orthogonal contrasts and the initial body weight was used as a covariate at the statistical analysis of the data. Statistical analysis was performed by using SAS. Animals fed CS had lower (P<0.05) intake of DM, EE, NDFap and NDFi than those fed StS, 50% of CS + 50% of StS, and 50% of CS + 50% of StH. The diet containing CS also decreased (P<0.05) the intake of CP and NFC compared to diets containing StH or StS associated to CS. Despite of the lower DM intake, cattle fed diets containing CS had greater TDN intake (P<0.05) compared to those fed StS. The average daily gain was greater (P<0.05) in cattle fed CS compared to those fed diets with StS or StH as the only roughage source. However, no difference was observed for animal body weight gain (P>0.05) among diets with CS and StS or StH. These data suggests that the mixture of corn silage with silage or hay of stylosanthes seems to be a great alternative to the use of corn silage for diets of beef cattle at the finishing phase.
Sponsored by FAPEMIG, CNPq and INCT-CA
Keywords: Average daily gain, feed conversion, legume silage