PSXIV-40 Effects of Different Diets on Fatty Acid Composition and Lipid Stability of Intramuscular Fat in DorperxThin-Tailed Han Crossbred Mutton Lambs.

摘要

The objective of this experiment was to investigate the effects of different diets on fatty acid composition and lipid stability of intramuscular fat in Dorper×thin-tailed Han crossbred mutton Lambs. Single factor completely randomized block design was used in the current study. A total of 30 healthy and six-month-old Dorper×thin-tailed Han crossbred mutton Lambs with similar body weight (38.7 ± 2.1 kg) were randomly divided into 3 groups with 10 lamb each. Lambs in control group (G1) were fed a basal diet, and those in experimental group (G2) were fed the basal diet supplemented with Allium Mongolicum regel powder (20 g/d each lamb). Lambs in experimental group (G3) were fed the basal diet supplemented with Fan Chu Bao (100 g/d each lamb) (Fermented feed name). The trial period lasted for 75 d, which consisted of 15 d of per-feeding period and 60 d of formal period. At the end of experimental period, four lambs were randomly selected from each group and slaughtered to collect the longissimus dorsi to measure fatty acid composition, malondialdehyde (MDA) and superoxide dismutase (SOD) contents. The results showed as follows: Compared with G1 group and G3 groups, 1) G2 group showed significantly higher contents of C18:2cis-6, C18:3n-3, EPA, DHA, PUFA, n-6 and the ratio of PUFA/SFA (P<0.05) in intramuscular fat, and lower content of C18:0 (P<0.05). 2) G2 group significantly up-regulated the SOD activity (P<0.05), down-regulated contents of MDA (P<0.05) in intramuscular fat. 3) There were linear relationships between the MDA content, SOD activty and PUFA contents (P<0.001) in intramuscular fat (R2=0.992). The contribution of MDA is negative for the multiple regression equation, whereas the SOD is positive. In conclusion, diet supplemented with Allium Mongilicum regel powder improved the fatty acid composition and oxidative stability effectively, which is significant in improving the quality of meat.