Abstract
<title>Abstract</title> <p>In this research, we report the growth performance, feed conversion ratio (FCR), condition factor, and nutrient retention of juvenile gilthead seabream (~ 212 g) cultured under different temperatures (24°C; 28°C; 32°C) consistent with the thermal range of the Red Sea. The results showed that growth performance was similar between 24°C and 28°C groups, while a significantly lower specific growth rate (SGR) was observed at 32°C. FCR was significantly affected by temperature, being lowest at 24°C, followed by 28°C, and highest at 32°C. Regression analysis showed that SGR and FCR were optimal at 25.9°C and 24.4°C, respectively. Feed intake was highest at 28°C and decreased significantly at 32°C. Body protein, lipid, and energy levels as well as their retention showed a decreasing trend as the temperature increased from 24 to 32°C. The condition factor also showed a decreasing trend. In summary, the results suggest that growth, feed intake, FCR, and overall status of gilthead seabream are better between 24°C and 28°C, and at higher temperatures up to 32°C there are significant detrimental effects on the biological performance of the fish. These observations support that culture of gilthead seabream in the Red Sea, should avoid the southern regions of the sea.</p>