In the first feeding experiment, the fish were divided
randomly into two groups (A and B), the groups, each
containing 700 fish, were reared in individual tanks in triplicate.
Group A was served as the control (non-coated MP diet) and
group B was fed with a diet of chitosan-coated MP.
The fish were fed with moisture pellets (MP) treated with
chitosan-coating solution (1% chitosan, 1% tamarind gum,
0.5% vitamin C, 0.3% glucosamin sulfate, 0.1% chitooligossacharide
and 0.5% asthaxanthin) which was sprayed onto the
surfaces of the MP at a flow rate of 1000 mL/min. The coated
MP diets were maintained for 11–24 h at −20 °C. Approximately
10% of the water was removed daily, along with the
waste feed and fecal material. Feed was provided by hand to
apparent visual satiety at a rate of 7% of the body weight of the
fish twice a day (07:00 a.m and 5:00 p.m).
The growth and mortality of olive flounders fed with chitosan-coated or
non-coated MP diets were evaluated for 12 weeks and weighed every
2weeks. The average growth of the chitosan-coated diet group increased by
approximately 10%, as compared to that of the control fish group (Fig. 1).
In addition, accumulation of mortality was reduced in the fish fed with the
chitosan-coated diet as compared with the non-coated diet group (Fig. 2).
These results might be induced froman improved fish tank environment, as
shown by the decreased COD and SS levels, and enhanced non-specific
immune response by chitosan