Effects of Lard Enriched with n-3 Polyunsaturated Fatty Acids on Serum Lipid Composition in Rats

This study evaluated the lard enriched with n-3 polyunsaturated fatty acids(PUFAs) on serum lipid composition in rats.The experiment contained two parts:(A) 20 crossed pigs(Landrace×Min, 60±2 kg) were assigned randomly into two dietary groups: a control group and a group fed the diet added 10% linseed based on the control diet.This part lasted 56 days and the results showed that the levels of the total n-3 PUFA in lard were improved approximately 2-fold(p<0.05), when pigs were fed 10% flaxseed compared to a control diet of corn.The lard taken from pigs was melted and preserved for rat experiment;(B) 45 Sprague-Dawley rats at day 36 were randomly fed one of three diets for 42 days: the diet without added fat, the diet contained 10% common lard from pigs fed a conventional corn ration and the diet contained 10% lard enriched with n-3 PUFA from pigs fed 10% flaxseed.Rats fed lard significantly increased(p<0.05) serum cholesterol levels compared with rats maintained on a diet without lard.However, rats fed the lard enriched with n-3 PUFA significantly decreased the level of low-density lipoprotein cholesterol in serum(p<0.05) and better hepatic antioxidant defense capacities, when compared with rats fed common lard(p<0.05).The results showed that pigs fed diet with n-3 PUFA produced lard enriched with n-3 PUFA and thus provided positive health benefits to the consumers.