Feedlot performance, carcass traits, and palatability traits of Hereford and Hereford x Brahman steers.

Abstract

Short-yearling steer of known genotypes-straightbred Hereford (100H, n = 80) 75% Hereford x 25% Brahman (75H:25B, n = 80), and 50% Hereford x 50% Brahman (50H:50B, n = 80) were sampled serially at four time-on-feed endpoints (84, 98, 112, 126 d) to compare feedlot performance and carcass and palatability traits of Hereford and Hereford x Brahman steers. After slaughter, USDA yield grade and quality grade factors were recorded, and a portion of the longissimus muscle was removed from the left side of each carcass and fabricated into four 2.54-cm steaks for palatability analyses. Paired steaks from each carcass were aged (6 and 18 d after death), and sensory panel and shear force evaluations were performed. At a constant live weight, 100H steers had higher ADG and produced less mature carcasses with smaller longissimus muscle areas and higher marbling scores than did 75H:25B and 50H:50B steers. The 50H:50B steers had the highest (P < .05) values for dressing percentage. Loin steak tenderness and juiciness decreased (P < .05) and shear force values increased (P < .05) as the percentage of Brahman breeding increased. EXtending the postmortem aging period from 6 to 18 d improved shear force values by 20% and panel tenderness ratings by approximately 14%. Beef from steers of the three breeds responded similarly to aging. When Certified Hereford Beef (CHB) specifications were applied, steaks from 100H steers and 75H:25B steers had similar shear force values, suggesting that beef from quarter-blood Brahman crossbred steers could be included in the CHB Program without detrimental effects on product tenderness.

Características de carcaça e da carne de novilhos Hereford terminados em confinamento com diferentes fontes de volumoso

“…Nos últimos anos, a pecuária de corte brasileira apresentou um bom ganho de produtividade, à medida que começaram a ser utilizados alimentos concentrados e de maior valor nutritivo para animais de raças precoces, mas com bom potencial de crescimento, como é o caso da raça Hereford (Sherbeck et al, 1995;Restle et al, 1999, Vaz & Restle, 2000. No entanto, embora os alimentos concentrados desempenhem papel fundamental para reduzir a idade de abate dos novilhos e, consequentemente, melhorar a qualidade da carne bovina visando atender consumidores cada vez mais exigentes (Restle & Vaz, 2002), ainda é a fração volumosa a que participa em maior proporção na dieta dos animais.…”

International perspective: characterisation of United States Department of Agriculture and Meat Standards Australia systems for assessing beef quality

“…Of factors considered of primary importance in determining tenderness and overall palatability of cooked beef in the MSA grading system, there is ample US research-study support for use of marbling (Smith et al 1969(Smith et al , 2007Savell et al 1987Savell et al , 1989George et al 1999;Wyle 2000;Platter et al 2003bPlatter et al , 2005Gruber et al 2006), maturity (Berry et al 1974a(Berry et al , 1974bSmith et al 1982Smith et al , 1988Smith et al , 2008Hilton et al 1998), amount of B. indicus genetics (McKeith et al 1985a(McKeith et al , 1985bSherbeck et al 1995Sherbeck et al , 1996O'Connor et al 1997), sex (Choat et al 2006;Tatum et al 2007), tenderstretch carcass suspension (Smith et al , 1979(Smith et al , 2007Orts et al 1971;Hostetler et al 1975), ultimate pH (Smulders et al 1990;Tatum 1991a, 1994;Eilers et al 1996;Wulf et al 1997), meat colour (Jeremiah et al 1972;Wulf et al 1997;Cannell et al 2000;Wyle et al 2003;Vote et al 2003), fat colour (Hilton et al 1998;Wyle et al 1998Wyle et al , 2003Wyle 2000;Vote et al 2003) and subcu...…”

“…Tatum (2006) believes that rather than continued, singular focus on measurement and categorisation of beef quality differences at the end of the production process, an alternative and more comprehensive approach -consistent with TQM philosophy -is to focus on understanding the causes of product variability and then work to improve the production process by measuring and monitoring critical variables known to affect variability in finished products. Colorado State University scientists used PACCP decision trees in studies by Sherbeck et al (1995Sherbeck et al ( , 1996 and Tatum et al (1997Tatum et al ( , 1998Tatum et al ( , 1999Tatum et al ( , 2000. ConAgra Beef, working with Colorado State University scientists (Anon.…”

Desempenho De Genótipos De Novilhos Para Abate Aos Catorze Meses, Gerados Por Fêmeas De Dois Anos

“…Quando o nível de suplementação na fase de recria aumentou para 1% do peso vivo, o mesmo autor verificou um maior ganho de peso no confinamento para os novilhos H (1,253 kg) do que para os ¾ H ¼ B (1,112 kg). Utilizando um nível de energia mais elevado ao empregado neste trabalho, para novilhos confinados dos 11 aos 15 meses, Sherbeck et al (1995) Moore et al (1975).…”