EFFECT OF A HIGH LINOLEIC-ACID DIET ON DELTA-9-DESATURASE ACTIVITY, LIPOGENESIS AND LIPID-COMPOSITION OF PIG SUBCUTANEOUS ADIPOSE-TISSUE

The effects of three diets were compared: a high linoleic acid diet(di et M containing 4 % maize oil), diet T containing 4 % beef tallow, and C, a conventional control diet, on Delta 9-desaturase activity and li pogenesis in pig subcutaneous adipose tissue. Diet M increased lipogen esis (estimated from the activities of acetyl-CoA-carboxylase, malic e nzyme and glucose-6-phosphate dehydrogenase), and decreased Delta 9-de saturase activity, in comparison to the other diets. Linoleic acid con tent was higher in the pigs fed diet M than in the other pigs (amounti ng to 26 % of total tissue fatty acids versus 15 %, respectively). The lower monounsaturated fatty acid content in adipose tissue of pigs fe d diet M compared to pigs fed other diets could be associated with the lower Delta 9-desaturase activity and the lower oleic acid content of diet M. The present study suggests that Delta 9-desaturase could be i nvolved in the regulation of monounsaturated fatty acid content and he nce in the quality of pig adipose tissue. (C) Inra/Elsevier, Paris.