Reducing crude protein in diet by stimulating ruminal microbial growth with essential oils

摘要

The objective of the study was to evaluate the effects of a Crude Protein (CP) level reduction in diet by formulating feed on Metabolizable Protein (MP) and stimulating microbial growth with a feed additive based on essential oils on steers zootechnical performances. Two groups of ten Blond d'Aquitaine beef steers were offered a diet consisted of 70% corn and 30% of a protein concentrate diet that differed in CP level: 35.5% CP and 133 g MP/kg in control group (C) vs 32.5% CP and 123 g MP/kg supplemented with 0.5% of a feed additive in trial group (MPEO). After a 95-day experiment, average daily gain, feed consumptions and feed conversion ratio did not differ (P>0.05). Feed MP utilization efficiency was improved by 4.2%> in MPEO group. This trial supposes that the feed additive based on essential oils contributed to support ruminal microbial growth and allowed for a 8.4%) reduction of CP level in the feed diet without affecting steers zootechnical performances.