The effects of dietary n-3 polyunsaturated fatty acids (PUFA) on the fatty acid composition, cholesterol
and fat-soluble vitamins of abdomen meat and hepatopancreas in a freshwater crayfish (Astacus
leptodactylus) were investigated. Results showed that dietary n-3 PUFA ameliorated the chemical quality
(fatty acid composition, cholesterol and fat-soluble vitamin content) of abdomen meat and
hepatopancreas in both female and male A. leptodactylus. Results also showed that, in general,
increasing concentrations of dietary n-3 PUFA lowered the deposition of oleic acid (18:1n-9), linoleic
acid (18:2n-6) and total n-6 PUFA, but simultaneously improved the deposition of eicosapentaenoic acid
(20:5n-3), docosapentaenoic acid (22:5n-3), docosahexaenoic acid (22:6n-3) and total n-3 PUFA in the
abdomen meat and hepatopancreas. For example, total n-3 PUFA in the male abdomen meat of control
(D1) was 25.1 2.1 (% of total fatty acids), but that of diet 4 (D4) was 33.8 2.1. In addition, it was found
that the n-3/n-6 ratio in the abdomen meat and hepatopancreas increased with an increased concentration of
dietary n-3 PUFA (0.94 0.39 for the abdomen meat of male crayfish fed D1 and 1.68 0.1 for the abdomen
meat of male crayfish fed D4; and 0.14 0.03 for the hepatopancreas of female crayfish fed D1 and
0.45 0.08 for the hepatopancreas of female crayfish fed D4). However, the level of cholesterol and fatsoluble
vitamins in the abdomen meat was unaffected by the dietary n-3 PUFA (except retinol and cholesterol
levels for the females). The best fatty acid composition, cholesterol and fat-soluble vitamin values in the
abdomen meat were obtained from the crayfish fed experimental D4. For example, 86.2 6.2 mg/100 g
cholesterol was found for the female crayfish fed D4, but that of 74.7 4.4 mg/100 g for the female crayfish
fed D1. In conclusion, dietary n-3 series fatty acid concentrations significantly improved the abdomen meat
quality of A. leptodactylus.
2015