Growth performance and feed efficiency of Asian redtail catfish (Hemibagrus nemurus) larvae in response to dietary shrimp protein hydrolysate

This study aims to evaluate the effects of dietary shrimp protein hydrolysate (SH) on the growth, feed efficiency, and digestive enzyme activity of Asian redtail catfish ( Hemibagrus nemurus ) larvae. Four isonitrogenous (45 % crude protein) experimental diets were prepared, incorporating SH0, SH2.5, SH5.0, and SH7.5 to replace 0 %, 2.5 %, 5.0 %, and 7.5 % of fish meal protein, respectively. Larvae received feed to satiation five times per day for 30 days. It was observed that SH5.0 diet resulted in the greatest weight gain, with comparable final body weight, percentage weight gain, daily feed intake, and specific growth rate to SH7.5. Furthermore, SH5.0 and SH7.5 groups reported significantly higher protein efficiency ratios than SH0 and SH2.5. Feeding with the SH5.0 diet led to optimal values for both feed conversion and survival. Whole-body composition also remained consistent across treatments. Intestinal protease activity was significantly lower in SH0, while amylase activity was highest in SH7.5. SH5.0 showed an elevated intestinal lipase activity but was not significantly different from the other groups, except SH0. Maximum protease activity of approximately 4.93 % was observed upon inclusion of SH. An inclusion level of 5.0 % SH was found to be optimal for enhancing growth performance and feed efficiency in H. nemurus larvae.