Comparartive Analysis of Clarias gariepinus Fingerlings Reared in Pond and Cage Systems in Umuagwo, Imo State, Nigeria

Abstract

A study was conducted to compare performance of Clarias gariepinus reared in bamboo cage and concrete pond systems. The cage system measured 2.5m by 2.5m x 2m while the pond system measured 10m x 10m x 15m in length, width and depth respectively. The experiment was conducted between March and August 2019. The cage system composed of a predator barrier net constructed with galvanized angle rod and ½ copper wire mesh. Fish net was made up of ½ netting materials (210 D/9), nylon twine (210 D/9 and 210 D/8) and ropes (10mm PE and 4mm PE, as house in which the fish fingerlings were stocked. The stocked fish were held captive in the fish net cage while water flowed through it. This was assigned Treatment 1 (T1) while the concrete system was assigned Treatment 2 (T2). Each of the treatments was stocked with 1,500 Clarias fingerlings of 10g average weight and managed simultaneously for a period of 184 days. Data were analysed using analysis of variance. Results showed 83.3% and 96.6% survival rates in cage and pond systems respectively. Average weight at harvest per fish ranged between 332.6g and 415.7g for cage system and 250.6g and 350.8g for pond system. The survival rate in cage culture (83.3%) was low due to high water current, as cage was floated, hence fingerlings could not maximize feed intake at the initial stage. Results of weight frequency showed varying degrees of importance. For the cage culture the percentage weights varied between 12% in the group belonging to 251 – 300g in size having 150 number of fish to 21.6% in the group of 401 – 451g size with 270 fish specimen while in pond culture it varied between 3.45% in 401 – 451g size with 50 fish to 41.38% in 201 – 250g size having 600 fish samples. Inference from these results indicated that cage system had bigger fish at harvest than the pond system. From the results, the cage fish culture is more profitable in terms of weight and biomass. However, adequate care should be taken to ensure maximum utilization of feed in cage culture system.