2009 Goat Carcass Evaluation
One of the goals of the Western Maryland Pasture-Based Meat Goat Performance Test is to evaluate and compare carcass characteristics of meat goats consuming a pasture-only diet. This year, nine bucks were selected for harvest. Two of the goats were purebred Kiko, one was fullblood Boer, and six were crossbred Kikos.
The bucks were transported from the test site at the University of Maryland’s Western Maryland Research & Education Center to LambCo, LLC for humane harvest on October 15, 2009. They were weighed immediately before harvest. Live weight (LW) ranged from 62 to 86 pounds and averaged 72 lbs. (32.7 kg). Hot carcass weights (HCW) were determined soon after harvest. Weights ranged from 24.8 to 34.9 lbs. and averaged 31.0 lbs. (14.1 kg).
For the nine goats, dressing percentage (hot carcass weight divided by live weight) ranged from 38.8 percent to 49.2 percent and averaged 43.1 percent. Dressing percentage (DP) for goats varies considerably and is affected by many factors, including sex, age, gut fill, and fat content.
The dressing percentages observed in these goats was within the expected range. The carcasses contained very little fat, as the goats had been consuming a pasture-only diet since early June. Grass-fed livestock also tend to have more gut fill.
After chilling overnight, cold carcass weights (CCW) were determined. Weights ranged from 23.8 lbs. to 33.6 lbs and averaged 29.9 lbs. (13.6 kg). Cold carcass weights are less than hot carcass weights, as the carcasses lose moisture during chilling. Cold carcass weights were used to calculate carcass yields.
Kidney and heart fat
Kidney and heart fat (KH) was removed from each carcass and weighed. While goats are known for depositing more internal fat than other livestock species, these goats had very minimal internal fat. Kidney and heart fat ranged from 0.121 to 0.435 lbs. (per carcass) and averaged 0.30 lbs. (0.66 kg). Percent KH fat ranged from 0.32 to 2.08% and averaged 0.98% of cold carcass weight.
Goats that are fed to the point that they deposit external fat would be expected to have much higher percentages of kidney and heart fat. I am reminded of a carcass study in Texas in which feedlot goats, fed to a high degree of finish, had 3 to 6 percent kidney and heart fat.
Rib eye area
Rib eye area (REA) was measured between the 12th and 13th rib using a grid. Each dot on the grid represents 0.1 square inches of measurement. There is a degree of subjectivity when using a grid to measure rib eye area. To reduce the subjectivity, each side of the rib eye was measured and an average value was used.
Rib eye measurements ranged from 1.45 to 2.20 square inches and averaged 1.79 square inches. The actual rib eye measurements were considerably larger (about 0.5 square inches) than the ultrasound measurements (U-REA). The goats had been ultrasounded on September 10.
Back fat (U-BF) was very minimal (less than 0.05 inches) and could not be differentiated between carcasses. In goats and lambs, body wall thickness (BWT) is considered to be a better indicator of fat cover. It was measured. It ranged from 0.30 to 0.55 inches and averaged 0.40 inches.
The carcasses were completely deboned. Fat and lean were separated from the bones, resulting in separate “piles” of bones, fat, and lean, which were weighed to determine carcass percentages. Fat trim ranged from 1.10 to 2.55 lbs. (per carcass) and averaged 1.78 lbs. (0.81 kg). Percent fat ranged from 3.6 to 10.1 percent and averaged 6.1 percent of cold carcass eight.
Bones ranged in weight from 8 to 11 lbs. (per carcass) and averaged 9.5 lbs. (4.3 kg). Bones comprised from 28.2 to 36.9% of cold carcass weight, an average of 32 percent. Lean tissue ranged from 14.3 to 21.8 lbs. (per carcass) and averaged 18.3 lbs. (8.3 kg). Percent lean ranged from 57.4 to 65.5 percent and averaged 60.9 percent.
As a percentage of live weight, lean ranged from 22.6 to 30.7 percent and averaged 25.4 percent. The buck with the highest percentage of lean (carcass and live weight basis) was a purebred Kiko consigned by Craig Adams from Litchfield, Illinois. Adams also had several of the top-performing bucks on test, including the high-selling buck. The other goat with outstanding carcass data was a 3/4 Kiko x 1/4 Spanish buck consigned by Wes Pinneo from Kincaid, Kansas.
Next year, we would like to harvest more goats from the test and perhaps incorporate a carcass contest into the performance testing program. For information about the goat carcass evaluation and/or Western Maryland Meat Goat Performance Test, contact Susan Schoenian at (301) 432-2767 ext. 343 or firstname.lastname@example.org. Information can also be found on the blog at http://mdgoattest.blogspot.com.
Thanks to everyone who helped to collect carcass data and take pictures: Susan Schoenian, David Gordon, Mary Beth Bennett, Dr. Nelson Escobar, and Dr. Scott Updike. Thanks to Dale Johnson for hauling the goats. Thanks to our consigners for letting us collect carcass data from their goats. Special thanks to LambCo, LLC for harvesting the goats and cutting up the carcasses.