|Rule, Daniel - UNIVERSITY OF WYOMING|
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: June 1, 1999
Publication Date: June 1, 1999
Citation: RULE, D.C., SHORT, R., GRINGS, E.E., GROSZ, M.D., MACNEIL, M.D. BREED EFFECTS ON CHOLESTEROL AND FATTY ACIDS IN LONGISSIMUS MUSCLE OF HEREFORD, LIMOUSIN, AND PIEDMONTESE F2 CROSSBRED CATTLE AT SLAUGHTER. JOURNAL OF ANIMAL SCIENCE SUPPLEMENT. 1999. v. 77(Suppl. 1). p. 166. Technical Abstract: Meat from cattle of breeds that differ in muscularity and(or) express muscular hypertrophy (double muscling) may differ in lipid composition. Hereford (H), Limousin (L), and Piedmontese (P) sires (20 to 25 per breed) were bred to crossbred cows at random to produce F1 calves. F1 progeny were inter se mated within sire breed to produce F2 calves that were weaned at 6 mo of age and placed on a growing diet until 341 kg for females and 386 kg for males. Calves were then fed a finishing diet for either 90 or 132 d and slaughtered. P cross calves were genotyped for the G-A transition mutation at the myostatin locus characteristic of P, and their genotypes were classified on the basis of having 0 (P0), 1 (P1), or 2 (P2) copies of the mutant allele (mhP). A 2.5-cm cross section of longissimus (LD) was sample from H (n=12), L (n=12), P0 (n=19), P1 (n=13), and P2 (n=12). Fat was separated from lean tissue. Both tissues were analyzed for cholesterol (CHOL) content and fatty acid (FA) composition by capillary column GLC. LD CHOL (mg/100 g) was greater (P=.01) for P2 (67.1) than for P0, L, and H (58.5, 60.6, and 59.2, resp.) and intermediate for P1 (62.4). Fat tissue CHOL was numerically highest for P2 (137.1 mg/100 g) but not different (P=.23) than the others (range 105.6-125.8). For LD FA, P2 had the lowest (P<.01) 16:0 (21.2%) and 18:1 (32.7%), whereas P2 had higher (P<.01) 18:0 (13.3%) than P1 or P0 but not H or L. P2 had the highest (P<.01) 18:2 (11.7%), 18:3 (.7%), and 20:4 (5.6%). In fat, P2 had higher (P<.01) 18:0 (17.2%) and 18:2 (2.3%). P0-2 had greater (P=02) 18:3 than H or L. We conclude P2 contain greater LD CHOL, and associated FA reflect this change by containing greater proportions of unsaturated FA.