Effects of combination of hydroxyproline, taurine and cholesterol on the growth and quality of turbot Scophthalmus maximus fed Clostridium autoethanogenum protein

Abstract

Clostridium autoethanogenum protein (CAP) is a promising protein source but high dietary level of CAP was proved to reduce the growth performance and quality of aquatic animals. In order to evaluate the combination of hydroxyproline, taurine and cholesterol (HTC, with the proportion of 1:1:2) to overcome the disadvantage of CAP, six experimental diets were formulated, in which CAP was used to replace 45 %, 60 % or 75 % of fishmeal protein in a fishmeal-based diet to prepared three diets and HTC was added to these three diets at the level of 2 % for another three diets. These diets were fed to turbot Scophthalmus maximus with the initial weight of about 211.6 g for 8 weeks. The results showed that HTC added to diets with 45 % and 60 % of fishmeal replacement levels led to significant increases in final body weight, weight gain rate, muscle springiness, muscle chewiness and expression of myod and myhc (P<0.05). Moreover, HTC added to diet with 75 % of fishmeal replacement level led to the increase of the proportion of myofibers with diameter longer than 200 μm. The muscle collagen content and the expression of col1a2, lox, timp2, myod and myhc genes was up-regulated by HTC, regardless of the CAP levels (P<0.05). In summary, this study provided evidence that supplementation of HTC to diet with high CAP level yield positive impacts on growth performance, muscle collagen content and muscle texture, possibly due to its ability to regulate genes for collagen synthesis and deposition and myofiber hypertrophy.

Keywords

• Clostridium autoethanogenum protein
• Taurine
• Hydroxyproline
• Cholesterol