Reuse of wastewaters from slaughterhouse and palm oil mill: Influence on the growth performance of catfish (Clarias gariepinus)

Integrating fish farming with wastewater recycling can improve fish farming programs, ensuring environmental sustainability while improving cost of fish farming. This study examines the influence of wastewaters from slaughterhouses and palm oil mils on the growth performance of catfish. Artificial ponds created with transparent buckets, where the fingerlings were grown for six weeks, contained each wastewater type comprising 30%, 40% and 50% wastewater, the rest being tap water. Tap water was used as the control. Live body weight, weight gain, live length and gain in length of fish were used to monitor fish growth performance on a weekly basis. Pond temperature and pH were also monitored weekly. The physicochemical parameters of the water in the ponds were above the standards required for fishponds. There was no significant difference between the growth performance parameters in the control and other treatments during the entire period of study. There was also a strong correlation (r ≈ 1) between the growth performance and the duration of study for all the treatments, indicating the fish could survive in the ponds for as long as necessary. Highest live weight of 14 g in T3R1, 13.33 g for control, 12 g for T2R1 and T4R1 were obtained. Highest live length values of 13.70, 13.50, 13.30, 13.20, 13.10 cm were obtained for T3R2, T3R3, T2R2, control and T2R3 respectively. Temperature in the adapted ponds ranged from 24–28 ℃, and pH raged from 6–8. A low mortality rate of 4.16% (4 deaths) was obtained in the case of T3R3 only for the first week, but there no other mortality in other treatments throughout the period of the study. Results obtained show that wastewaters from slaughterhouses and palm oil mills can effectively be used to grow fish, reducing cost of fish farming and ensuring environmental sustainability from dumping of the wastewaters.