Acclimatization, Growth and Breeding Performance of African Catfish Clarias Gariepinus) in Pond Culture System of Pakistan

Abstract

The aquaculture system of Pakistan is mainly extensive and in some areas are semi-intensive having low stocking density, culture of low value fish species and low per unit fish production (2.5 ton per ha). It is high time to move towards intensive aquaculture by introducing high value fish species with high growth and export potential. The African catfish may serve as potential candidates as it can be stocked at higher densities, can attain maximum weight of 16-40 tons/ha. In addition, they have high consumer preference due to fewer bones, good meat, adaptability to wide range of environmental conditions and disease resistance. Therefore, current study was planned to introduce commercially important African catfish in aquaculture system of Pakistan. The germplasm of African catfish was obtained from Thailand and shifted to AFP (Aquaculture and Fisheries Program) of NARC (National Agriculture Research Centre), Islamabad for further experimentation. The fish was acclimatized in local environmental conditions and exhibit a highly cannibalistic behavior at early stage, which was controlled by segregating it on size basis. The feeding experiments were performed to develop a cost-effective fish feed from locally available ingredients and feeding strategies for optimal use of feed. It was concluded that African catfish should feed three times a day at rate of 4% body weight with a feed of 35% crude protein level containing 20% animal source of protein. The effect of different stocking densities in monoculture was also studied. The culture of African catfish in earthen ponds at stocking densities of 15,000 to 20,000 fish per acre gives highest production and profitability compared to stocking of 10,000 fish/ acre. African catfish was easily bred through induce breeding {the most important factor for the introduction of new species} in the local environment. A female fish of about 1 kg gave good results in the terms of fertilization rate (%) hatching rate (%) and a handsome number of hatchlings was obtained by the artificial breeding. These experiments provided knowledge base and rational for development of African catfish culture under the prevailing environmental condition of the region. Intensive culture of this fish could be beneficial for the improvement of aquaculture industry in Pakistan.