Journal des sciences vétérinaires et du diagnostic médical

Effects of Dietary Substitution of Cod Liver Oil by Vegetable Oils on Fatty Acid Composition in Liver and Muscles, Lipoprotein Lipase Gene Expression and Intestinal Histomorphology in Juvenile Nile Tilapia (Oreochromis niloticus)

Abeer E. Azizia, Walaa F.Awadin, Nevien K. M. Abdelkhalek and Yousef Y.Elseady

 Effects of Dietary Substitution of Cod Liver Oil by Vegetable Oils on Fatty Acid Composition in Liver and Muscles, Lipoprotein Lipase Gene Expression and Intestinal Histomorphology in Juvenile Nile Tilapia (Oreochromis niloticus)

This study aimed to investigate the effect of dietary substitution of cod liver oil (CLO) by vegetable oils on fatty acid composition in liver and muscles and histomorphology of proximal, mid and distal intestine in juvenile Nile tilapia (O. niloticus). Fish in duplicate were fed five isonitrogenous and isocaloric diets [cod liver oil (CLO), linseed oil (LO), olive oil (OO)] or a blend of equal proportions of CLO and vegetable oils (CLO : LO, CLO : OO) at 3 % of the diets for 60 days. The levels of lipoprotein lipase (LPL) gene expression significantly increased in the fish liver had CLO: LO diet and significantly decreased in liver of fish had OO diet.Meanwhile, nonsignificant increase of LPL geneexpression was shown in muscle of fish fed on CLO and LO diets Histomorphometric measurements made in the intestinal tract revealed that, with the exception of the luminal diameter, number of the mucosal folds and width of the lamina propria, the other histomorphometric parameters were significantly higher in the three parts in LO group than in CLO: OO and OO groups.