PD/A CRSP Aquanews-Summer 2002
Use of Local Technology to Promote Aquaculture Development in Sagana, Kenya
by D. Liti and J. Munguti
Moi University and Sagana Fish Farm, Kenya
Students Short-term Experiments at Sagana Yield Tangible Benefits
by D. Liti and J. Munguti
In parallel with longer-term research investigations, side experiments are conducted at Sagana by undergraduate students in fulfillment of their senior projects. Results from these experiments have been quite interesting. In one instance, ponds were treated with lime and common salt to simulate the well known productive soda lakes, of which Lake Turkana in Kenya is an example. The student project demonstrated that treatment of limed earthen ponds with common salt lead to a remarkable increase in fish growth.
Sagana and the CRSP
D/A CRSP activities at Sagana Fish Farm have greatly enhanced the reputation and visibility of Saganas research in sustainable aquaculture.
In the current PD/A CRSP work plan, research at Sagana is aimed at improving production of fish protein and fish seed. Two investigations are underway: 1) Evaluation of Growth and Reproductive Performance of Three Strains of Nile Tilapia, Oreochromis niloticus, Found in Kenya for Use in Aquaculture; and 2) Development of Economically Feasible Feeds for Semi-Intensive Culture of Tilapia, Oreochromis niloticus, Using Locally Available Agricultural By-Products.
Aquaculture ponds at Sagana Fish Farm, Kenya.
Picture By: Mwangi Mbugua
Evaluation of Growth and Reproductive Performance
Three Nile tilapia strains from Lake Victoria, Lake Turkana, and Sagana are being evaluated to determine the best strain that can be recommended to farmers. Although the strain experiment is in its initial stages, there are indications that the Lake Victoria strain may have the best performance in terms of growth.
Development of Economically Feasible Feeds
Single ingredients of agricultural by-productswheat bran, maize bran, and rice branhave been evaluated and recommended to farmers. Wheat and maize bran have proved through previous experiments to be better feed supplements for Nile tilapia than rice bran. The latter performed poorly due to adulteration by the suppliers. In fact, rice performed only marginally over the fertilizer treatments despite having the same cost per unit weight as the other two brans.
In addition to the single ingredients, locally available commercial feeds have also been evaluated as feed supplements for Nile tilapia. Research at Sagana has established that diets formulated for pigs perform as well as the commercial diets formulated for tilapia. Moreover, as pig diets are cheaper than tilapia diets, their use increases profitability.
Analysis of commercial feeds con-ducted at the Sagana laboratory has shown that some commercial feeds do not meet the specifications given by the manufacturers. Moreover, the feeds are unreasonably expensive.