Substitution effect of broccoli (Brassica oleracea var. italica) by‐product for Saccharina japonica in feeds on growth, carcass chemical composition, and air exposure resistance of abalone (Haliotis discus, Reeve 1846)

Abstract

Substitutability of broccoli by‐products (BBP) for Saccharina japonica in feed on growth, carcass chemical composition, and air exposure resistance of abalone (Haliotis discus) was investigated. One thousand and two hundred sixty abalones were randomly assigned into 18 cages (3 cages/diet; 70 abalone/cage). Two hundred g/kg of S. japonica was included in the control diet (BBP0). The BBP250, BBP500, BBP750, and BBP1000 diets were prepared by substituting 250, 500, 750, and 1000 g/kg of S. japonica with an equal amount of BBP. Additionally, dry S. japonica was prepared. Abalone were fed daily for 7 days a week for 16 weeks. Following the completion of the feeding trial, 20 abalone from each cage were exposed to air for 20 h prior to being monitored for the following 5 days. The greatest weight gain and specific growth rate (SGR) were achieved in abalone fed the BBP250 diet. Superior survival was obtained in abalone fed the BBP250, BBP500, BBP750, and BBP1000 diets to abalone fed the S. japonica control diet. The BBP250 and BBP500 diets achieved the highest survival of abalone. BBP appears to be a novel replacer for S. japonica in abalone diets, and 250 g/kg replacement of BBP for S. japonica produced the best weight gain and SGR.