Effects of saccharicterpenin-supplemented diets on body composition, activity of intestinal enzymes, blood lipid and intestinal histology of juvenile turbot (Scophthalmus maximus)

Abstract:

A 64-day feeding tiral was conducted to evaluate the effects of supplemental saccharicterpenin in diets on body composition, activity of intestinal enzymes, blood lipid and intestinal histology of juvenile turbot, Scophthalmus maximus. Six isotrogenous and isolipidic practical diets was supplemented with six levels of saccharicterpenin, in which 0(D₀), 25(D₂₅), 50(D₅₀), 75(D₇₅), 100(D₁₀₀), 200(D₂₀₀) mg/kg saccharicterpenin were supplemented respectively. Results showed that: No significant difference was found in the moisture content and crude protein of whole fish and dorsal muscle(P>0.05). Crude lipid content of whole fish in D₁₀₀ and D₂₀₀ was significantly lower than that in D₀ group (P<0.05). Crude lipid content of dorsal muscle in D₇₅ was significantly higher than D₀ group (P<0.05). Crude ash of whole fish in D₂₅ and D₅₀ groups was significantly lower than that in other groups (P<0.05), and D₂₀₀ group was significantly higher than D₂₅, D₅₀ and D₇₅ groups (P<0.05). Saturated fatty acid content and monounsaturated fatty acid content of dorsal muscle had no significant difference in each group with the increasing dietary saccharicterpenin(P>0.05). Except D₇₅ group, other groups of polyunsaturated fatty acid content were significantly higher than D₀ group(P<0.05). Serum triglyceride and total-cholesterol concentration decreased with increasing dietary saccharicterpenin levels, but only D₂₀₀ was significantly lower than D₀ group(P<0.05). No significant difference was found in LDL-cholesterol concentration in all groups(P>0.05). Trypsin activities of the intestine first increased significantly then declined as dietary saccharicterpenin level increased(P<0.05). Lipase activities in D₂₅-D₇₅ groups were significantly higher than other groups (P<0.05). No-significant difference in the amylase activity of intestine was found between groups(P>0.05). Microvilli length in D₅₀ group exhibited obviously higher than D₀ group. Mucosal fold length of the foregut tissue showed a remarkable ascending trend from D₂₅ to D₇₅ group(P<0.05). No-significant difference in intestinal villi length was observed from D₀ to D₁₀₀ group(P>0.05), however, D₅₀ group was significantly higher than D₂₀₀ group (P<0.05). Therefore we can draw that saccharicterpenin addition can effectively increase polyunsaturated fatty acid content, decrease blood lipid, improve the digestive enzymes activities and intestinal histology of juvenile turbot.