EFFECTS OF DIFFERENT TEMPERATURE AND FEEDING RATE ON GROWTH PERFORMANCE, BODY COMPOSITION AND BLOOD PARAMETERS OF ASIAN SEA BASS (LATES CALCARIFER)

This study aimed to investigate the effects of different temperatures (20, 27 and 33 °C) and two feeding rates (2.5 % biomass per day and satiation) on growth performance, body composition, hematology and blood biochemistry of Asian sea bass (Lates calcarifer). For this purpose, 8 fish with an average initial weight of 99.55 ± 0.24 g were randomly transported to 200 liters tanks (6 treatments with three replicates) and fish feeding was done using a commercial feed for 6 weeks. At the end of the experiment, the growth performance, blood indices and chemical composition of fish carcasses were measured. The results of this study showed that the feeding rate of biomass (2.5%) and satitation had no significant effects on growth performance and nutrition of this fish (P<0.05). However, different levels of temperature showed a significant effect on these indices (P <0.05). The average final weight of fish grown at 33 °C and fed at the biomass level was higher than other treatments, although this difference was not significantly different from that of the stored group at 27 °C. Among the hematology parameters, the number of red blood cells showed significant changes among treatments (P<0.05). Plasma biochemical parameters such as triglyceride, glucose and cholesterol level were significantly affected by water temperature and feeding rates (P <0.05). The activity of liver enzymes in plasma was not significantly different in different treatments (P <0.05). The protein and lipid content of fish carcasses increased with increasing temperature so that the group stored at 33 °C had the highest protein and lipid content (P <0.05). In general, the results of this study showed that temperatures above 27 °C are more optimal for this species and the feed rates of biomass and satiation have no significant effect on the growth and health performance of this fish in this temperature range.