Nutrient digestibility and enzyme activity of microbial floc, Tetraselmis chuii, and Spirulina platensis fed on Juvenile Cobia (Rachycentron canadum)

Abstract

Cobia is a relatively new species of marine carnivorous fish with high aquaculture potential because of its fast growth (4-6 kg in a year) and ability to adapt and reproduce in the cultivation environment. This study aims to evaluate the nutrient digestibility and enzyme activity of cobia juveniles fed pelleted feed with microbial floc meal (MF), microalga Tetraselmis chuii (MT) meal, and microalga Spirulina platensis (MS) meal. Fish were fed pellets twice a day at satiation. The results showed that MS feed had higher and significantly different (p<0.05) of protein digestibility, enzyme activity, amylase and lipase, glycogen and lipid in the liver of juvenile cobia than MF feed. These two raw materials generally had no negative effect on cobia juvenile growth. Conversely, the value of nutrient digestibility and enzyme activity of MT feed could not be determined because the fish did not consume the feed.