摘要
This study aimed to evaluate feed efficiency and meat quality of 31 three-crossbred beef heifers during 84 days in a feedlot system. A 60:40 concentrate and sorghum silage ration on DM basis (ME = 2.73Mcal/kg of DM, CP = 11.90% DM) was fed ad libitum. Based on residual feed intake (RFI) calculations, the heifers were ranked in three groups of feed efficiency: High RFI (average mean = 0.776; n = 9), medium RFI (average mean = -0.010; n = 11), and low RFI (average mean = - 0.624; n = 11). High RFI heifers consumed 4.56% more DM per day than low RFI heifers (P <0.05). The ADG did not differ (P> 0.05) among RFI groups (1.40kg/day). No differences (P>0.05) were detected for digestibility of the nutrients: DM (64.00%), CP (60.01%), crude fat (72.90%), NDF (54.80%) and non-fibrous carbohydrate (NFC) (78.91%). There were no differences between low and high RFI groups for slaughter weight (475.00 vs. 479.55kg), hot carcass weight (259.09 vs. 261.44kg), Longissimus dorsi (LD) area (69.02 vs. 68.11 cm2), back-fat thickness (5.74 vs. 6.26 cm), shear force (5.45 vs. 5.19kg), sensorial traits of LD muscle, LD color (intensities L=40.47 a*=24.74 and b*=16.13) or commercial cuts yield. Low RFI heifers presented similar meat quality and carcass traits as high RFI heifers, however low RFI heifers consumed less DM (kg/d)
摘要译文
这项研究的目的是评估饲料效率和31三牛杂交母牛肉质期间84天在饲养场的Systema 60:40精矿和高粱青贮饲料日粮干物质基础（ME \x3d 273Mcal / kg干物质，CP \x3d 1125，DM）供给的广告在残余饵料摄取libitumBased（RFI）的计算，小母牛分别排在三组饲料效率：高RFI（平均均值\x3d 0;N \x3d 9），中的RFI（平均均值\x3d -0; N \x3d 11），和低的RFI（平均均值\x3d - 0; N \x3d 11）高的RFI母牛消耗每天425更DM比低的RFI小母牛（P 0助理总干事没有差异（P 0 RFI组（1G /天）没有差异（对营养物质消化率检测P 0中：DM（6425），CP（6025）粗脂肪（7225），NDF（5480％25）和非纤维碳水化合物（NFC）（7825）有对屠宰重量（475vs479g），热胴体重低和高的RFI组之间没有差异（259vs261克），背最长肌（LD）区（69vs68cm2），背膘厚度（5vs6cm），剪切力（5vs5g），LD肌肉的感官性状，颜色LD （强度L \x3d 40A * \x3d 2474和b * \x3d 16或商业切割yieldLow RFI母牛提出类似的肉质和胴体性状高RFI小母牛，但是低RFI母牛消耗更少的DM（千克/天）
REIS, Simone Frotas dos et al.. Feed efficiency and meat quality of crossbred beef heifers classified according to residual feed intake.[J]. Revista Brasileira de Saúde e Produção Animal, 2015,16(3): 632-642