Evaluation of feed stimulants in diets for sea bream (Sparus aurata)

Abstract

Six isoprotein and isolipidic diets were formulated to investigate the effect of dietary additives on growth and feed efficiency of sea bream (Sparus aurata) fry fed a fishmeal-based diet for 80 days. The additives (protorsan, hydrolyzed fish protein, squid meal, krill meal, and betaine + inosine-5'- monophosphate) were added to the diets at the expense of fishmeal. The specific growth rates of the fish ranged from 2.17-2.18% per day for the protorsan and control groups to 2.42% per day for the group fed the squid additive. Significant differences (p<0.05) in final body weight and specific growth rate were detected only between the protorsan and control groups and the squid additive group. The feed conversion ratio ranged from 1.04 in the group fed hydrolyzed fish protein group to 1.24 in the group fed krill with no statistically significant differences (p>0.05) between treatments. The feed stimulating action of taurine was tested by observation. Pellets coated in a taurine solution were more actively consumed than control pellets during the morning feeding but consumption did not differ during the afternoon feeding.