Corn Starch as a Dietary Seaweed Powder Replacer in Juvenile Abalone, Haliotis discus hannai

Abstract This study was conducted to investigate the use of corn starch ( CS ) as a replacer of seaweed powder ( SWP ) in the diets of juvenile abalone, Haliotis discus hannai . Six experimental diets were formulated with CS to replace SWP at 0, 20, 40, 60, 80, and 100% (Con, CS 20 , CS 40 , CS 60 , CS 80 , and CS 100 , respectively). Abalones averaging 0.44 ± 0.01 g (mean ± SD ) were distributed into 18 tanks, and fed one of the six experimental diets in triplicate for 10 wk. After the feeding trial, abalone fed CS 100 had a lower weight gain ( WG ) and specific growth rate than abalone fed the other diets; however, there was no significant difference among abalone fed Con, CS 20 , CS 40 , CS 60 , and CS 80 . Abalone fed Con, CS 20 , and CS 40 had a higher feed efficiency and protein efficiency ratio than abalone fed CS 100 diet, although there were no significant differences among abalone fed Con, CS 20 , CS 40 , CS 60 , and CS 80 . Abalone fed CS 100 had a lower whole‐body crude lipid content than did abalone fed Con. Broken‐line analysis for WG indicated that dietary SWP was successfully replaced by CS up to 74.8%. Based on growth performance, CS could replace more than 74.8% but less than 80% of SWP in juvenile abalone diets.