Effect of dietary CLA administration on fatty acid composition and lipogenic and lipolytic enzyme activities in suckling and weaned piglets

The objective of this study was to determine the effects of conjugated linoleic acid (CLA) administration during the lactation and post-weaning period or in the post-weaning period exclusively on fatty acid (FA) composition and enzymatic regulation in suckling and in 63-d-old piglets. During the nursery phase, 18 piglets individually penned were used and three dietary treatments (n = 6) were applied: (1) piglets that proceeded from control sows fed a control diet (0 g CLA/kg) (CT-CT), (2) piglets from control sows fed a diet containing 10 g CLA/kg (CT-CLA) and (3) piglets from CLA fed sows fed diets containing 10 g CLA/kg (CLA-CLA). Suckling piglets (28 d of age) from sows fed the CLA enriched diet showed higher concentration of saturated FA (SFA), lower concentration of total monounsaturated FA (MUFA) and lower MUFA/SFA, C16:1n-7/C16:0 and C18:1n-9/C18:0 ratios in subcutaneous backfat than those from sows fed the control diet (P<0.05). No CLA isomers were detected at weaning in the subcutaneous backfat of piglets from sows fed the control diet, but 0.44 g/100 g total FA (TFA) c9,t11-CLA and 0.12 g/100 g TFA t10,c12-CLA were observed in piglets from CLA fed sows. Also, increased c9,t11-CLA, t10,c12-CLA and SFA proportions (P<0.05) and decreased MUFA and MUFA/SFA and C16:1n-7/C16:0 ratios were found in the liver of piglets from CLA fed sows (P<0.05). In 63-d-old piglets, malic enzyme activity in subcutaneous fat was lower in groups in which CLA was fed to sows and piglets or only to piglets than in the group that did not receive any CLA supplementation (P<0.05). No effect of dietary CLA on heart L-3-hydroxyacyl-CoA dehydrogenase and glucose-6-phosphate dehydrogenase and malic enzyme activity in liver was observed. The concentration of c9,t11-CLA and t10,c12-CLA at weaning was negligible in piglets from sows fed the control diet, but after being fed for 35 d the diet enriched with CLA, the concentration was similar to that of piglets fed milk and diet containing CLA. Little alteration of enzyme regulation induced by CLA feeding was found in piglets either at 28 or 63 d of age, except for malic enzyme activity, which was lower in 63-d-old piglets fed the CLA enriched diet after weaning.