Summary of workshop
Recommendations
Cassava is a staple food for over 200 million Africans and can thrive even on infertile soils, adverse climatic conditions and low input management. Cassava and its byproducts-peel, leaves and stems-have the potential satisfy the energy demands for both humans and livestock if the demonstrated agronomic potential is fulfilled. The objectives of this workshop were, therefore, to explore avenues for utilizing Cassava and its by-products for livestock feed, firstly using materials surplus to human requirements, and secondly when tuber production is insufficient to meet human needs.
Cassava tuberous roots are basically used as human food in sub-Saharan Africa, hence their use as livestock feed has low priority and limited to times of local surplus production or when infrastructural inadequacies may restrict marketing and distribution.
Studies indicate that Cassava and its by-products in fresh and dry forms can be fed to different classes of livestock. For nonruminants, tubers can be fed at levels between 20-50% of dry matter intake, and peel and leaves can also be used. Biological constraints to the amounts of Cassava which can be incorporated in livestock feeds include low protein and high cyanide content. Other constraints include microbial contamination during prolonged drying using traditional methods, and the dustiness of Cassava meal.
Traditionally, peel and leaves are fed to ruminants, but excellent supplementary feeds can be formulated from tubers in combination with low cost nitrogenous sources.
1. To compensate for the low protein content, and the deficiency in sulfur amino acids in Cassava tuberous roots, the use of high protein plant and animal feed stuffs to balance diets for non ruminants is recommended. For ruminants offered cassava-based rations, the use of low cost nitrogen sources such as urea, Leucaena and poultry manure should be explored.2. For livestock feed, the levels of cyanide in Cassava products should not exceed 100 ppm (total HCN). There is need for a simple and reliable method for the determination of total HCN. In this regard, a simple but reliable method should be developed into a simple package for use by extension workers
3. For storage of dried cassava, the moisture content should not exceed 14%. Low cost, rapid drying methods should be developed to reduce the level of microbial contamination in the dried product. Simple packaging techniques are also needed since dried cassava is hygroscopic. Simple drying facilities could be organized through cooperative farmers' groups at village level.
4. For feed compounders, the addition of vegetable oil, animal fat, or molasses reduce the dustiness of compounded feed and increases palatability. Where economically viable, pelletizing of the compounded ration is also recommended.
5. While insufficient cassava is available to meet human demands, the use of cassava by-products for animal feed is recommended. By-products are of low value, and their use at village level should be encouraged by smallholder farmers to supplement ruminant livestock. By-products from food processing units if not used immediately should be sun-dried to allow for storage. If sufficient quantities are available, feed compounders should explore the economics of the inclusion of cassava peel in livestock feed formulations.
6. Surplus cassava production leads to price instability. The additional market that would be created if tubers were thus used for animal feed would improve price stability for the commodity, to the benefit of producers and consumers, and would encourage the adoption of improved varieties and agronomic production practices.
