Relation of residual feed intake and production of gases in Nelore cattle

• Grant number: 11/18153-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2011
• End date: October 31, 2012
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Production
• Principal Investigator: Saulo da Luz e Silva
• Grantee: Fernando de Oliveira Bussiman
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil

Abstract

The goal is to evaluate the existence of a relationship between the RFI and the production of gases (CO2 and CH4) in the animals, using the technique of in vitro fermentation for 12 hours. The hypothesis to be tested is that the volume of gas produced is related to the RFI and that one can deduce the feed efficiency of Nellore cattle by in vitro gas production. 72 Nellore cattle will be used, with an initial average weight of 380kg and approximately 18 months old. The animals are going to be confined to diets containing 85% concentrate and 15% bulky. After an adjustment period of 21 days and, after approximately 18 hours of fasting, the animals will be weighed. For 72 days the animals are going to be fed daily, containing the diet: dry corn grain (50%), refinazil (27.1%), in natural sugar cane bagasse (15%), mineral core (2.3%), and Rumensin ® (0.03%) to the determination of the RFI. Then 20 animals will be selected, 10 high RFI and 10 low RFI. Each animal will be collected one liter of rumen fluid to perform in vitro assays. It Will be fermented for 12 hours 10g of treatment that the animal is consuming and, the volume of gas (CH4 and CO2) will be measured and analyzed in chromatography.(AU)