Retail cut-out and U.S.D.A. yield grade data were obtained on 1,121
carcasses of steers from Hereford and Angus dams mated artificially to
Hereford, Angus, Jersey, Limousin, South Devon, Simmental and Charolais
bulls. Calves were weaned when approximately 215 days old, conditioned
28 days, fed an average of 218 days after weaning before being slaughtered
in a commercial slaughter plant. Carcass cooler data were obtained and
the right side of each carcass was cut into closely trimmed, essentially
boneless retail cuts at the KSU food service building.
Beef yield grades do reflect definite differences in retail yields.
Statistical tests indicated less than one chance in 1,000 that such differences
occurred by chance and that the yield grade differences were
real.
The average difference in retail product percentage between yield
grades was 4.6 percent. The average difference in fat trim percentage
was 5.6 percent. For 700-pound carcasses, that's a difference of 39.2
pounds of waste fat, or 32.2 pounds of retail product. The difference in
bone percentage would account for the other 7 pounds.
