The effect of ultrafiltered fish protein hydrolysate level on growth performance, protein digestibility and mRNA expression of PepT1 in juvenile turbot (Scophthalmus maximusL.)

Abstract

The intention of the study was to investigate the effect of ultrafiltered fish protein hydrolysate (UF) level on growth, feed utilization, apparent digestibility coefficients and proximal intestine peptide transporter 1 (PepT1) mRNA level for juvenile turbot (Scophthalmus maximus L.). Experimental diets (UF‐0, UF‐5, UF‐10, UF‐15 and UF‐20) were prepared containing about 68% plant protein, and fish meal protein was, respectively, replaced by 0%, 5%, 10%, 15% and 20% UF of dietary protein. Diet PP contained about 78% plant protein, and diet CAA contained about 10% crystalline amino acid mixture. All diets were fed to seven triplicate groups of turbot (initial weight 16.05 ± 0.03 g) for 68 days. Fish fed diet UF‐10 had an increasing tendency in growth compared with diets contained UF, while dietary UF level was not significantly correlated with specific growth rate and feed intake. Feed efficiency, protein efficiency ratio and protein productive value significantly correlated with dietary UF level, and fish fed diets contained low‐level UF had higher digestibility than that diets UF‐0, PP and CAA. There was a decreasing tendency in PepT1 expression level with dietary UF level. The results indicated that low‐level UF showed a positive effect on growth and feed utilization in juvenile turbot.

The differences in postprandial free amino acid concentrations and the gene expression of PepT1 and amino acid transporters after fishmeal partial replacement by meat and bone meal in juvenile turbot (Scophthalmus maximus L.)

“…Our results showed similar patterns with previous studies that intestinal PepT1 expression level peaked 2 h after re‐feeding. Furthermore, present study demonstrated that compared with the FM diet, MBM diet increased the gene expression of intestinal PepT1, which was agreed with other findings in turbot (Wei, Liang, Mu, Zheng & Xu ), but was dissimilar to previous studies on Sea Bass ( Dicentrarchus labrax ) (Terova et al . ) and Yellow Perch ( Perca flavescens ) (Ostaszewska, Dabrowski, Kamaszewski, Kwasek, Grodzik & Bierla ).…”

Amino acid absorption and protein synthesis responses of turbot Scophthalmus maximus to lysine and leucine in free, dipeptide and tripeptide forms

“…Generally, EAAs in plant protein‐based diets can be supplemented to closely match ideal amino acid (AA) balance for optimum growth (Furuya et al, ). Previous studies reported that fish protein hydrolysates mainly containing a mixture of small peptides, and free AAs had a positive effect on the growth and feed utilization in fish fed high plant protein diets (Aksnes, Hope, Jönsson, Björnsson, & Albrektsen, ; Wei, Liang, Mu, Zheng, & Xu, ; Zheng, Liang, Yao, Wang, & Chang, ). In fact, EAAs of the formulated diets exist in the forms of free AA, peptide or protein bound (Zhang, Dabrowski, Hliwa, & Gomulka, ).…”

The effect of ultrafiltered fish protein hydrolysate levels on the liver and muscle metabolic profile of juvenile turbot (Scophthalmus maximusL.) by1H NMR-based metabolomics studies

“…; Li, Mai, Trushenski & Wu ; Chao, Huo, Cheng, Tsai, Liao, Lee, Qin, Hsieh, Pao & Peng ; Wei et al . ). Proline is considered as a functional amino acid for fish because it is a substrate for protein synthesis, one of major extracellular components in connective tissue, the synthesis of polyamines, arginine and glutamate, antioxidative reactions and immune responses (Wu, Bazer, Burghardt, Johnson, Kim, Knabe, Li, Li, Jason, McKnight, Satterfield & Spencer ; Zhao, Han, Ren, Ma, Li & Peng ).…”

“…FPH, particularly ultrafiltered fish protein hydrolysate (UF) containing high levels of mall molecular weight compounds, is of excellent quality, in terms of amino acid profile, and may be another avenue for reducing aquaculture's dependence on fish meal (Zheng et al . ; Zheng, Liang, Yao, Wang & Chang ; Wei, Liang, Mu, Zheng & Xu ).…”