Effects of feed restriction on fatty acid composition of meat and adipose tissues in pig

摘要

In experiment 1, effects of feed restriction on fatty acid composition and cholesterol level of meat (loin) and adipose tissues (subcutaneous fat and intermuscular fat) were in vestigated using 18 Land-race x White Yorkshire x Duroc barrows. The animas were allocated into three groups receiving full feeding (control), 80 percent and 60 percent of full feeding, respectively. Samples of loin (m. longarisumus) were collected between 12th and 13th vertebrate 24 hours after slaughtering. There was no obvious effect of feed restriction on total lipids level in loin and the values were all similar among the groups. Proportions of palmitoleic and linoleic acids in total lipids in loin decreased with feed restriction athough other fatty acids stayed at the same levels. While there was no large difference in loin neutra fatty acid composition among three groups, mrystic, palmitic, palmitoleic, linoleic acids, and degree of saturation on polar lipids, varied significantly (P<0.01) among the groups. Cholesterol levels tended to be lower with higher feed restrictions but no statistica significance was obtained. In experiment 2, loin, perirena, subcutaneous and intermuscular fat taken from norma and soft fat barrows determined by palpation were subjected to fatty acid composition and cholesterol analyses. Loin samples of the soft fat pigs had a slightly lower total lipids level compared with those of the norma pigs but significantly higher (P<0.05) proportions of oleic and linoleic acids. This observation agrees with involvement of higher levels of oleic acid in occurrence of soft fat pigs. Compared with the normal pigs, the soft fat pigs had a largely lowered (P<0.01) cholesterol level.