Jana Pickova

Differences between lipid content and composition of different parts of fillets from crossbred farmed carp (Cyprinus carpio)

Common carp (Cyprinus carpio) is, globally, one of the most important farmed fish species. We have analyzed carp from a natural pond-production system in South Bohemia. Ongrowing fish had access to an abundant plankton population which was supplemented with cereals. Fatty acid composition (FA) was investigated in three parts of fillets from four crosses of carp. The FA composition of the leanest part, the dorsal white muscle was similar to that of marine-farmed species; it contained a large proportion of n-3 highly unsaturated FA, the n-3/n-6 ratio was 1.1, and the proportion of phospholipids was high. The abdominal wall is rich in monounsaturated FA, the n-3/n-6 ratio is lower, 0.5, and it is more affected by the cereal feed. We concluded that the lipid composition of all these carp tissues can be improved in terms of healthy FA profile.

Feeding steam-pelleted rapeseed affects expression of genes involved in hepatic lipid metabolism and fatty acid composition of chicken meat

&NA; This study investigated the dietary effect of steam‐pelleted rapeseed (RS) diets with different inclusion levels on the fatty acid composition of chicken meat and the expression of lipid metabolism‐related genes in the liver. Experimental diets included 6 different wheat‐soybean meal based diets either in nonpelleted or steam‐pelleted form supplemented with 80, 160, and 240 g RS/kg feed and one nonpelleted wheat‐soybean meal based diet without RS supplementation as the control. These diets were fed to newly hatched broiler chickens (Ross 308) for 34 days. Compared to the control diet, steam‐pelleted diets containing 160 or 240 g/kg RS significantly increased the content of omega‐3 long chain polyunsaturated fatty acids (n‐3 LC‐PUFA) in the breast and drumstick, while their meat yields were not affected. Moreover, the mRNA levels of fatty acid desaturase 1 (FADS1) and acyl‐coenzyme A oxidase 1 (ACOX1) in their livers increased. Therefore, steam‐pelleted diets with 160 or 240 g/kg RS can be used to increase the n‐3 LC‐PUFA content in chicken meat without compromising meat yield.