Prediction of retail beef yield and fat content from live animal and carcass measurements in Nellore cattle.

Data from 156 Nellore males were used to develop equations for the prediction of retail beef yield and carcass fat content, expressed as kilograms and as a percentage, from live animal and carcass measurements. Longissimus muscle area and backfat and rump fat thickness were measured by ultrasound up to 5 d before slaughter and fasted live weight was determined 1 d before slaughter. The same traits were obtained after slaughter. The carcass edible portion (CEP in kg and CEP% in percentage; n = 116) was calculated by the sum of the edible portions of primal cuts: hindquarter, forequarter, and spare ribs. Trimmable fat from the carcass boning process, with the standardization of about 3 mm of fat on retail beef, was considered to be representative of carcass fat content. Most of the variation in CEP was explained by fasted live weight or carcass weight (R(2) of 0.92 and 0.96); the same occurred for CEP% (R(2) of 0.15 and 0.13), and for CEP, the inclusion of LM area and fat thickness reduced the equation bias (lower value of Mallow's Cp statistics). For trimmable fat, most variation could be explained by weight or rump fat thickness. In general, the equations developed from live animal measurements showed a predictive power similar to the equations using carcass measurements. In all cases, the traits expressed as kilograms were better predicted (R(2) of 0.39 to 0.96) than traits expressed as a percentage (R(2) of 0.08 to 0.42).

Ratio between height and width of longissimus muscle as an indicator of retail beef yield / Razão entre altura e largura do músculo longissimus como indicador do rendimento de cortes cárneos de bovinos

The technique of ultrasound is a noninvasive method performed in vivo. The technology has been used to measure carcass traits as longissimus muscle area (LMA), subcutaneous fat and marbling. It allows accurate data measures with no animal slaughter and a greater number of animals evaluated in a period, resulting in economic benefit. Some technicians recommend the use of the relation between longissimus muscle height and width as a better indicator trait of retail beef yield than LMA itself. The purpose of this study was to calculate the ratio between longissimus muscle height and width (RATIO) in order to estimate the simple correlation between RATIO, obtained in vivo, and dressing percentage (DP%), retail beef yield expressed in kg (YIELD_kg) and percentage of retail beef yield (YIELD_%), obtained after slaughter. A total of 116 Nellore bulls born between 2006 and 2009, with an average age and weight of 18 ± 1.10 months and 437 ± 60 kg at slaughter, which were raised and finished at Centro APTA Bovinos de Corte, Sertãozinho, São Paulo, Brazil, were used. Among 116 animals, 33 were slaughtered in 2008, 34 in 2009, 25 in 2010 and 24 in 2011. Before slaughter images were obtained by ultrasound between the 12th and 13th ribs, transversely over the longissimus muscle with immobilized animals in containment chamber, using the ultrasound machine Pie Medical 401347 - Aquila (Esaote Eu

O artigo não apresenta resumo em português.

Ratio between height and width of longissimus muscle as an indicator of retail beef yield / Razão entre altura e largura do músculo longissimus como indicador do rendimento de cortes cárneos de bovinos

The technique of ultrasound is a noninvasive method performed in vivo. The technology has been used to measure carcass traits as longissimus muscle area (LMA), subcutaneous fat and marbling. It allows accurate data measures with no animal slaughter and a greater number of animals evaluated in a period, resulting in economic benefit. Some technicians recommend the use of the relation between longissimus muscle height and width as a better indicator trait of retail beef yield than LMA itself. The purpose of this study was to calculate the ratio between longissimus muscle height and width (RATIO) in order to estimate the simple correlation between RATIO, obtained in vivo, and dressing percentage (DP%), retail beef yield expressed in kg (YIELD_kg) and percentage of retail beef yield (YIELD_%), obtained after slaughter. A total of 116 Nellore bulls born between 2006 and 2009, with an average age and weight of 18 ± 1.10 months and 437 ± 60 kg at slaughter, which were raised and finished at Centro APTA Bovinos de Corte, Sertãozinho, São Paulo, Brazil, were used. Among 116 animals, 33 were slaughtered in 2008, 34 in 2009, 25 in 2010 and 24 in 2011. Before slaughter images were obtained by ultrasound between the 12th and 13th ribs, transversely over the longissimus muscle with immobilized animals in containment chamber, using the ultrasound machine Pie Medical 401347 - Aquila (Esaote Eu

O artigo não apresenta resumo em português.