The United Junior Suffolk Sheep Association (UJSSA) recently sponsored the presentation “Hitting the Target for Lamb Yield Quality and Value.” Dr. Travis Hoffman, assistant professor of animal sciences and Extension sheep specialist at North Dakota State University, was the seminar’s featured speaker.
Hoffman began by emphasizing that there is no best breed of sheep for achieving high quality lamb yield. “As far as my own personal experience goes, my family decided to go with Corriedale sheep, but that’s just what worked best for us,” he said. “It’s important to note that what we’re discussing here today should be considered with and applied to whatever variety of sheep you stock your flock with.”
He said that making producers aware of what quality of meat their animals are producing is vitally important. Awareness of carcass evaluation criteria can help producers make decisions aimed at meeting lean meat yield and quality expectations.
“There isn’t just one thing a producer can do to optimize the quality of their yield. It’s important to look at the entire cycle,” he explained. “There are many things to consider, from the genetics and condition of the breeding stock to all the antemortem factors such as diet, care and age at slaughter. Postmortem circumstances like storage and handling, muscle pH, refrigeration and cooking conditions will all contribute to how the quality of that lamb is rated.”
Hoffman said that flock owners looking to improve the grade of their lamb must first learn just how those grades are determined. He outlined the four grades of lamb carcass and five yield grades of lamb, yearling mutton and mutton carcasses:
- Prime – Lamb carcasses having minimum conformation qualifications for the Prime grade tend to be thickly muscled throughout, are moderately wide and thick in relation to their length and have moderately plump and full legs, moderately wide and thick backs and moderately thick and full shoulders
- Choice – Carcasses having minimum conformation qualifications for Choice are slightly thickly muscled throughout, tend to be slightly wide and thick in relation to their length and tend to have slightly plump and full legs, slightly wide and thick backs and slightly thick and full shoulders
- Good – Lamb carcasses having minimum conformation qualifications for the Good grade are slightly thinly muscled throughout, are moderately narrow in relation to their length and have slightly thin, tapering legs and slightly narrow and thin backs and shoulders
- Utility – The Utility grade includes those lamb carcasses whose characteristics are inferior to those specified as minimum for Good
How the yield grades are determined:
- Yield Grade 1 – A carcass in Yield Grade 1 usually has only a thin layer of external fat over the back and loin and slight deposits of fat in the flanks and cod or udder. There is usually a very thin layer of fat over the top of the shoulders and the outside of the legs. Muscles are usually plainly visible on most areas of the carcass.
- Yield Grade 2 – Grade 2 usually has a slightly thin layer of fat over the back and loin and the muscles of the back are not visible. The top of the shoulders and the outside of the legs have a thin covering of fat and the muscles are slightly visible. There are usually small deposits of fat in the flanks and cod or udder.
- Yield Grade 3 – A carcass in Yield Grade 3 usually has a moderately thick covering of fat over the back. The tops of the shoulders are completely covered, and the legs are nearly completely covered, although the muscles on the outside of the lower legs are visible. There usually are slightly large deposits of fat in the flanks and cod or udder.
- Yield Grade 4 – Grade 4 usually is completely covered with fat. There usually is a very thick covering of fat over the back and a slightly thick covering over the shoulders and legs. There usually are large deposits of fat in the flanks and cod or udder.
- Yield Grade 5 – A carcass in Yield Grade 5 has an adjusted fat thickness of more than 0.45 inches. The external fat covering on most parts of the carcass is usually greater than that described for Yield Grade 4.
There may be some trial and error at first, Hoffman cautioned, but close observation and recordkeeping will reveal which practices have brought about the meat earning the higher grades and with the most pleasing taste to the consumer.
Once a producer has identified which breeding, dietary, care, slaughter, handling and preparation practices produces the lamb with the best flavor, producers can maximize both demand for their product as well as profits for their operations.
“Always remember,” Hoffman concluded, “the reason people will eat your lamb is because of its flavor. And the reason people won’t eat your lamb is because of its flavor.”
For more information visit the UJSSA at suffolks.org/youth.php.
by Enrico Villamaino