Submitted to: American Society of Animal Science Southern Section Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 11/30/2002
Publication Date: 2/1/2003
Citation: BURKE, J.M., APPLE, J.K., ROBERTS, W.J., BOGER, C.B. 2003. COMPARISON OF CARCASS TRAITS OF EXTENSIVELY RAISED HAIR BREED LAMBS. AMERICAN SOCIETY OF ANIMAL SCIENCE SOUTHERN SECTION MEETING. 81(Suppl. 2):27. Interpretive Summary:
Technical Abstract: The objective was to compare live animal performance and carcass characteristics of 7/8 Dorper (DO; n = 5), 3/4 Dorper (DX; n = 25), purebred Katahdin (KA; n = 20) and St. Croix (SC; n = 17) lambs born in February (FEB) and October (OCT) 2001, and FEB Suffolk (SU; n = 10) lambs. After weaning, lambs were fed up to 1 kg corn/SBM while grazing bermudagrass or ryegrass. From weaning to harvest, ADG was greater for DO, DX, and SU than KA and SC lambs (P < 0.01). Lambs (FEB: 209 ± 1.9 d of age; OCT: DX, 201.3 ± 6.9; KA, 218.8 ± 8.7; SC, 230.4 ± 7.4 d of age or 40.3, 40.6, 35.8 ± 0.84 kg) were transported to the University of Arkansas Red Meat Abattoir for harvest. At harvest, DO, DX, KA, SC, and SU lambs weighed 40.2, 38.0, 38.4, 34.1 and 45.9 kg, respectively (P < 0.01). Carcass quality and cutability data were collected after a 7 d aging period at 2 degrees C. Carcasses from SU lambs were heavier than all other breed types (P < 0.01); whereas, fat thickness and yield grades of DO and KA were greater than DX, SC, and SU (P < 0.01). Longissimus muscle (LM) areas of DO, DX, and SU were greater than that of SC (P < 0.01). Kidney fat weights and percentage of internal fat were greatest from SC and least from SU carcasses (P < 0.01), resulting in a greater cooler shrinkage in SU carcasses (P < 0.01). Lean maturity was similar among breed types; however, skeletal and overall maturities were greatest from SU carcasses (P > 0.01; P < 0.05). Carcasses from SC lambs had lower flank streaking scores than DX and KA, with DO and SU carcasses receiving intermediate scores (P < 0.05). Conformation scores for DO, DX, and SU carcasses were markedly higher (P < 0.01), resulting in higher (P < 0.01) quality grades than SC carcasses, with KA receiving intermediate scores. L* values of the LM were lighter (P < 0.05) in KA and SC, redder (P < 0.01) in DO and DX than SC and SU, and more yellow (P < 0.01) in DO than SC. Results from this study indicate that ADG, carcass muscularity and quality was similar among Dorper and Suffolk lambs and, although fatter, carcass muscularity of Katahdin was similar to that of 3/4 Dorper lambs.