Influence of body condition score on carcass characteristics and subprimal yield from cull beef cows.

Abstract

Mature beef cows (n = 83) were slaughtered to measure the influence of body condition score (BCS) on carcass characteristics and subprimal yields. All cows were weighed and assigned BCS, based on a 9-point scale, 24 h before slaughter. Cows were slaughtered, and, after a 48-h chilling period, quality and yield grade data were collected on the left side of each carcass. The right side was quartered, fabricated into primal cuts, and weighed. Each primal cut was further processed into boneless subprimal cuts, minor cuts, lean trim, fat, and bone. Cuts were progressively trimmed to 6.4 and 0 mm of external and visible seam fat. Weights were recorded at all stages of fabrication, and subprimal yields were calculated as a percentage of the chilled carcass weight. Live weight, carcass weight, dressing percentage, fat thickness, longissimus muscle area, muscle:bone ratio, and numerical yield grade increased linearly (P = .0001) and predicted cutability and actual muscle-to-fat ratio decreased linearly (P = .0001) as BCS increased from 2 to 8. Carcasses from BCS-8 cows had the most (P<.05) marbling. The percentage of carcasses grading U.S. Utility, or higher, was 16.7, 20.0, 63.6, 43.3, 73.3, 100.0, and 100.0% for cows assigned a BCS of 2, 3, 4, 5, 6, 7, and 8, respectively. At 6.4 mm of fat trim, carcasses from BCS-5 cows had higher (P<.05) shoulder clod yields than carcasses from cows having a BCS of 6, 7, and 8. Carcasses of BCS-2 cows had lower (P<.05) strip loin yields than carcasses from BCS-3, 4, 5, 6, and 7 cows. Top sirloin butt yields were higher (P<.05) for carcasses of BCS-2, 3, 4, and 5 cows than those of BCS-6, 7, or 8 cows. Carcasses from BCS-7 and 8 cows had lower (P<.05) tenderloin and inside round yields than carcasses of BCS-5, or less, cows. At both fat-trim levels, carcasses from BCS-5 cows had higher (P<.05) eye of round yields than cows assigned BCS of 2, 7, or 8. When subprimal cuts were trimmed to 6.4 mm of visible fat, carcasses from BCS-5 cows had higher (P<.05) total lean product yields than cows assigned a BCS of 2, 4, 7, and 8. Regardless of fat trim, total fat yields increased (P = .0001) and total bone yields decreased (P = .0001) linearly as BCS increased from 2 to 8. Although carcasses from BCS-5 and 6 cows had the highest yields of lean product, cattle producers and packers may benefit most by marketing and(or) purchasing BCS-6 cows because a higher percentage of their carcasses had quality characteristics deemed desirable for fabrication into boneless subprimal cuts.

Development of the body condition score system in Murrah buffaloes: validation through ultrasonic assessment of body fat reserves

“…The difference might be attributed to the age group of animals. The mean ± SE (mm) values of carcass fat thickness at the point between 12th and 13th ribs for the scores 1 to 5 ranged from 1.67 ± 0.07 to 7.82 ± 0.21, whereas the values recorded by Apple et al [2] by assigning scores to beef cows on a 9 point scale ranged from 0.5 ± 1.5 to 27.3 ± 1.5. The difference in the fat thickness measurements might be attributed to the species differences.…”

Effects of days on feed, roughage sources and inclusion levels of grain in concentrate on finishing performance and carcass characteristics in cull beef cows

“…2). According to the findings of Apple (1999), Apple et al (1999) and Shemeis et al (1994), the rib eye areas of cow carcasses increased as the body condition score increased. Additionally, Shemeis et al (1994) reported that age at slaughter had an affect on the rib eye areas of cow carcasses.…”

Carcass boneless yield of Braford steers, classified according to fat coverage class

“…Apple et al (1999) observed that total de-boned lean meat was 66.4; 70.0; 69.9; 71.8; 70.8; 67.7; 64.5%, respectively, for 2, 3, 4, 5, 6, 7, and 8 body condition scores (scales from 1 to 9). Those authors also found total bone percentage ranged from 16.9% (8 body condition score) to 31.6% (2 body condition score), although the variation among the steers studied by Apple et al (1999) was wider, inasmuch as steers with a body condition score of 2 were considered thin.…”

“…The present study determined 5.18% mean discarded trimmings, which decreased as carcass finishing degree was reduced (P<0.05). Apple et al (1999) observed total fat trimmings of 1.9, 3.2; 5.4; 4.5; 8.2; 13.2 and 18.6%, respectively, for body condition scores of 2, 3, 4, 5, 6, 7 and 8. Koch et al (1981) evaluated the dressing percentage of 686 carcasses of feedlot-finished steers of different breeds and reported yields of 66.4, 21.9, and 11.7% for commercial cuts, discarded trimmings, and discarded bones, respectively, in Hereford × Angus animals, and 74.3, 11.5, and 14.2%, in Chianina steers.…”