The development of tilapia feeds based on locally available materials in Zambia
Nakambala Tilapia Farm commenced operations at the Nakambala Estate of the Zambia Sugar Company near Mazabuka, Zambia in early 1982. The farm used an intensive tank system designed to produce 50 tonnes of tilaplas per annum to provide fish for feeding the labour force on the sugar estate. The project had to manufacture fish feeds on site. A wide range of feed raw materials were used over the course of the project, with formulations designed to aim to supply the nutrient levels suggested by the University of St iIng, Institute of Aquaculture. The raw materials included microalgae from a pilot scale algae culture project funded by the Overseas Development Administration, dried fish, blood meal, carcase meal, soyabeans, cottonseed, hydrolysed feather meal, sunflower oilcake, lucerne, leucaena, yeast, wheatings and maize. Dis involved identification of raw material supplies, development of appropriate feed processing methods, formulation of feeds and manufacture of the feeds. Seventeen feed trials were carried out to evaluatet he use of different feed formulations. Many of these trials concentrated on the supply of vitamins in the feeds as the provision of a vitamin supplement was made impossible by restrictions on foreign exchange allocations. The main conclusions were 1. The poor financial performance of the farm in the initial years of operation was due to problems in project implementation, particularly the absence at the start of the project of a breeding population of tilaplas of a species with proven growth potential in an intensive system. 2. The feeds being produced by 1985 were adequate to sustain good growth in tilapias. Feed trials had shown that there was no need to use a vitamin supplement in the feeds despite advice to the contrary from other authorities. 3. The farming system utilised was appropriate to Zambian conditions, despite being extremely intensive.