|Davila El Rassi, G.|
Submitted to: American Society of Animal Science Southern Section Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 12/5/2006
Publication Date: 2/7/2007
Citation: Davila El Rassi, G., Banskalieva, V., Albers-Nelson, R., Velasco, M., Brown, M.A., Roy, C. 2007. Fatty acid composition, including CLA's isomers and cholesterol content of m. longissimus lumborum and m. semimebranosus of Katahdin, Suffolk, Katahdin x Suffolk, and Suffolk x Katahdin lambs [abstract]. American Society of Animal Science Southern Section Meeting, February 3-6, 2007, Mobile, AL. p. 14. Available on-line: http://www.asas.org/southern/meetings_past.asp. Interpretive Summary: ABSTRACT ONLY
Technical Abstract: Lipids in meat products have important human health implications. Muscle tissues from Katahdin (KK), Suffolk (SS), Katahdin x Suffolk (KS), and Suffolk x Katahdin (SS) lambs were analyzed to determine the effect of breed-type on muscle fatty acid composition, including conjugated linoleic acid (CLA) isomers, and cholesterol content. Lambs were grazed on bermudagrass after weaning in the spring for approximately 82 days. Two months prior to harvest, lambs were fed a high-concentrate diet and were slaughtered at 248 d of age. The cholesterol content and fatty acid composition (FAC), including CLA isomers were analyzed in m. longissimus lumborum (LL) and m. semimebranosus (SM). There was little evidence of differences in the cholesterol content among the muscles and breed groups (range: 57 - 67 mg/100 g tissue). The muscles of SS and SK lambs contained more (p<0.05) sterified fatty acids (SFA) than the muscles of KK and KS. In contrast, the proportions of monounsaturated fatty acids (MUFA) were higher (P<0.01) in the three KK, KS and SK breeds, compared to SS lambs. The proportion of SFA was greater (P<0.001) in LL than in SM, whereas the content of MUFA was similar in the two muscles. The levels of omega-3 fatty acids were not different between muscles and among the breeds. The sum of omega-6 fatty acids in both muscles of KK, KS and SK was lower (P<0.01) than SS, reflecting on a lower (P<0.01) omega-6/omega-3, ratio in these groups. The ratio polyunsaturated fatty acids (PUFA) to SFA did not differ between KK, KS and SS, but was lower (P<0.05) in SK. The content (mg/100g tissue) of the main 9-cis,11-trans CLA isomer in the muscles of KK, KS and SK lambs was two times higher (P<0.01) than in the muscles of SS animals. Across all breeds, no differences in CLA content between muscles were observed. The inherent breed characteristics of KK and SS lambs seemed to influence the CLA content and muscle FAC of the crossbred KS and SK lambs. Higher concentrations of omega-6/omega-3 and CLA in purebred KK was reflected positively in the crossbred KS and SK, suggesting that the Katahdin breed may be a useful foundation for crossbreeding in US lamb production.