ASSESSMENT OF AFRICAN CATFISH (CLARIAS GARIEPINUS) PERFORMANCE UNDER VARIED WATER TEMPERATURES AND PHOTOPERIODS

Abstract

Clarias Gariepinus is the most cultured fish species in Nigeria. The knowledge of the cultured condition of the most economical fish species will increase the performance of the species. This research determined the performance and behavioural characteristics of African Catfish under different water temperature and photoperiods (Light/Dark, Total Light, and Total Dark). In investigating the performance of catfish under varied temperature and photoperiod, eighteen units of experiments were carried out. Ninety (90) juveniles weighing an average of 5.8g were used. In each unit, 5 juveniles were placed in a water filled 50 litre container containing a thermostat to regulate the water temperature. The eighteen units were divided into 3 batches of six units each. The first batch of the experiment was placed in total dark environment for 24hrs during the experimental period. The second and third batch of the experiment was placed in a sealed room with the only source of light coming from a fluorescent white bulb. In each of the batches, the water temperature in two units was regulated to 26 oC, another two units at 28 oC and the last two units at 30 oC. Adequate power supply was provided throughout the entire period of the experiment. The Juvenile in each unit were fed to satiation once a day with the feed consumed measured. No death of the juveniles was recorded during the period of the experiment. Feed consumed daily were recorded and the weight gained of juveniles were measured weekly. Anova analysis was used to analysis the data collected. It was discovered that 30 oC water temperature is the optimal water temperature for rearing catfish irrespective of photoperiod (Total Dark, Total Light, and Light/Dark). At 30 oC water temperature, growth performance, feed conversion ratio and feed consumption of juveniles is good when compared to other juveniles reared at a lower water temperature (26 oC and 28 oC).However, at all water temperature (26 oC, 28 oC, and 30 oC), juveniles raised under a complete Dark photoperiod had a better feed conversion ratio, and lower aggression when compared with Juveniles raised under other photoperiods. Therefore, Total dark photoperiod is the optimal photoperiod for rearing

catfish irrespective of temperature. Total dark photoperiod reduces the aggression and locomotive movements of catfish. Long and continuous photoperiods stimulate feed efficiency and enhance the growth in Catfish juveniles