32. Whatever plans are made and implemented there will still remain some risk that livestock production in the Zambezi Valley could get out of hand at a future date. Is it possible to promote settlement and agricultural development in the Zambezi Valley without tsetse control and the introduction of livestock?
Draught assistance through mechanical tillage
33. Tractors are one alternative to the introduction of cattle for the alleviation of rural draught constraints. Zimbabwe has one of the best mechanical tillage support programmes for rural farmers in Africa, partly because of the infrastructure supporting the substantial commercial farming sector.
34. Mechanical tillage services are offered to peasant farmers through the Ministry of Local Government's District Development Fund. A number of tractors have been purchased privately by individual peasant farmers or by cooperatives under credit schemes offered by the Agricultural Finance Corporation (AFC), including schemes in the Zambezi Valley (e.g. Mutimba, 1984). Some Non-Governmental Organizations have also promoted rural tractor schemes (Oxfam, Lutheran World Federation, Freedom from Hunger) including a recent project at a resettlement scheme within the tsetse belt (The Herald, 1989).
35. Foreign exchange constraints for replacement and maintenance of equipment have been steadily increasing in the recent past and this situation may deteriorate even further. With appropriate government policies, mechanical tillage could make a significant contribution to the future development of tsetse-infested agricultural lands. However, for many rural farming communities, and particularly those in more marginal areas, the economics of animal draught power remain more attractive. Furthermore, tractors are unable to provide the other benefits (milk, manure, investment) offered by cattle.
36. Mechanical tillage should be seen as a complement rather than as an alternative to animal draught power. Indeed, policies directed towards the establishment of viable mechanical tillage programmes in tsetse-freed areas could be important in reducing the likelihood of overstocking with cattle and consequent environmental degradation.
Draught assistance through donkeys
37. While donkeys are susceptible to trypanosomiasis they appear able to survive and remain productive in tsetse-infested parts of Zimbabwe at higher levels of challenge than local cattle can tolerate. Introduction of donkeys may offer an alternative approach to alleviating draught constraints.
38. The use of donkeys for draught power in areas cleared of tsetse by selective game elimination has been officially encouraged in the past (Boys et al, 1972). When the Nembudzia area of Sebungwe was first settled in 1963, donkeys were introduced in large numbers while cattle were prohibited: it was believed at that time that donkeys were unattractive hosts for the fly, which proved not to be the case (Robertson, 1983, pages 38 and 67). Since tsetse control at that time was based on host elimination, further introduction of donkeys was subsequently prohibited.
39. In the past donkeys have also been used extensively within tsetse areas by the Tsetse and Trypanosomiasis Control Branch itself, as pack animals for field teams. These animals required prophylactic treatment with Samorin while under trypanosomiasis challenge. A disadvantage of donkeys in comparison with cattle is that they sometimes suffer adverse reaction to the curative drug Berenil (Boys et al, 1971).
40. Today in Zimbabwe donkeys are used extensively for ploughing, transport and general draught purposes in some rural communities while elsewhere the animal is not used at all. The advantages and disadvantages of donkeys in comparison with cattle do not appear to have been fully researched in this country. As with tractors, the value of donkey draught power may be more as a complement rather than as an alternative to cattle draught power.
