Growth, Feed Utilization, Apparent Digestibility and Fatty Acid Composition of Beluga (Huso huso) Juveniles to Different Inclusion Levels of Whole Seed Meal of Faba Bean (Vicia faba)

This study was conducted to evaluate the inclusion of whole faba bean (Vicia faba) meal (WFBM) on growth, feed utilization, apparent digestibility, and flesh fatty acid composition of juvenile beluga (Huso huso) (n = 144; initial weight = 82 g) at six levels 0 (control), 5, 10, 15, 20, and 25%) in a completely randomized design (each with three replicates) in 18 tanks (250 L) for 56 days. Growth performance, final weight, weight gain, average daily growth rate, and feed efficiency of fish fed diets containing 0, 5, and 10% WFBM were higher (P <= 0.05) compared to other groups; and the poorest values (P <= 0.05) were attained in the fish fed with 25% WFBM. Feed conversion ratio values showed rising trend with significant differences (P <= 0.05) by increasing WFBM levels in diets containing 20 and 25% WFBM (0.79-0.82). Apparent digestibility of dry matter, protein, and lipid contents relatively decreased (P <= 0.05) with increasing levels of WFBM from 10 to 25%. Flesh fatty acid composition showed elevated total n-6 fatty acids (P <= 0.05) whereas the content of total n-3 decreased (P <= 0.05) with increasing of the incorporated WFBM level. The ratio of n-3/n-6 significantly declined (P <= 0.05) with raising the incorporated WFBM level. A decreasing trend in eicosapentaenoic and docosahexaenoic acids contents and a relatively increasing trend in oleic and linoleic acids contents were obtained in treatments with high dietary WFBM levels (P <= 0.05). According to the results, WFBM can be included only up to 10% of juvenile beluga diet without any adverse effects on growth, digestibility, and flesh fatty acid composition.