Behavioural response, welfare, and performance of Nile tilapia (Oreochromis niloticus) under different water temperatures

This work was carried out to detect behavioural response, performance and welfare of Nile tilapia fingerlings under different water temperatures. Fingerlings were reared in eight 90-L aquaria in duplicate for 60 days with 15 fish per aquarium at different temperatures (20 °C (group1), 24 °C (group 2), 28 °C (group 3), and 32 °C (group 4). The results showed that group 4 was higher in surfacing, surface swimming and aggressive behaviour than other groups. While, group 3 was higher in middle swimming behaviour and crossing test than other groups, but bottom swimming behaviour was higher in group 1 than other groups. Also final body weight of group 3 was markedly greater than other groups, finally, it is concluded that a temperature 28 °C is the optimum for achievement of Nile tilapia welfare due to high body weight, lowering in surfacing, scratching and aggressive behaviour, increasing the ability of Nile tilapia for practicing swimming behaviour.