PSVIII-15 - Is There Any Relationship Between Metabolize Energy and Fecal Starch in Nelore Cattle Under High Grain Finishing Diets?

Abstract: There are some evidences in the theoretical library related the potential of starch digestibility in the whole tract with EM intake. However, there a lack of datas, mainly in Nelore cattle that is the most common beef breed raised in Brazil regarding this subject.The goal of this study was to evaluate if there was any relationship between ME and FS. The datas used to carry out these analysis came from a trial with different diets. The ME datas were generated from the NRC (1984) that ME=0.82 DE. Therefore, through intake datas were calculated the ME. FS datas were provided from the same trial. FS analyses have been made using NIRS equations to Nelore Cattle developed by (Caetano et al., 2009; Caetano et al., 2019). To perform Statistics Analyses , was used a GLM mode by SAS® as well as ANOVA test to obtain the best slope. Related the EM intake datas there were N= 93 read and FS datas there were = 97. The outcome provided by Statistics Analyses were not significant among linear up to cubic regressions. The best fitted model was a cubic regression although the R² were not significant,P < 0.01 R²=0.04. The model was EMI=1.8 x FS-0.069xFS²+0.00076x+FS³+15.42. Therefore, by those datas there were not any relationship between ME intake and FS. However, more datas should be used to enhance this prediction, due to some authors such as (Harmon, 2004; McLeod et al., 2008) tried to figure out the effects of energy intake on starch digestibility in different sites. it appears that energy is much more related to fat synthesis enzymes (McLeod et al., 2008; Baldwin et al., 2006; Girard et al., 1997), not interfering in starch digestibility that might be much more related to grain processing methods than EM intake, (Owens and Zinn ., 2011).