Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Animal, Dairy, and Veterinary Sciences

Committee Chair(s)

Lyle G. McNeal


Lyle G. McNeal


Daren P. Cornforth


Thomas D. Bunch


Thirty-seven Columbia and Cormo Crossbred July-weaned weather lambs were utilized in this study. A feeding trial was conducted to evaluate feed efficiency, average daily gain, feed cost per pound of gain, wool growth per day and per pound of grain, and average wool fiber diameter and distribution of fiber population of the wool. Lambs were raised to a uniform market weight of between 115 and 125 pounds and slaughtered to evaluate carcass weight, backfat thickness, loin eye area, internal body fat, leg circumference, dressing percentage, untrimmed wholesale cuts, trimmed retail cuts, and yield and quality grades. Suffok x Cormo/Rambouillet lambs were most efficient (P < .05) in converting feed to gain, gaining .15 kg per kg feed intake. They also had the highest daily gain (P < .05), and lowest cost per kg gain (P < .01) of any treatment, .29 kg and 0.75 respectively. Columbia lams had .32 cm of wool growth per kg of grain, and Cormo x Columbia lambs had the finest fiber diameter (P < .01) at 19.84 microns. No significant differences existed between treatments for any of the carcass traits observed. However, birth date and age at slaughter did have a negative effect on the percentage of trimmed retail cuts yielded by each carcass.