C. de HAAN
Introduction
The world bank's experience with livestock projects in tsetse-affected zones
Research and development requirements
Conclusion
Africa's tsetse-affected areas constitute one of the Continent's few underutilized resources and could play a pivotal role in alleviating its food deficit, provided appropriate research and development strategies are adopted to develop this potential. On the other hand, inappropriate land use could lead to major resource degradation in this zone. Livestock could make an important contribution to land use sustainability, provided appropriate technologies are developed to control the main diseases and improve the poor nutritional levels. In this presentation I propose to review briefly the World Bank's experience with livestock development in the tsetse-infested areas and identify from those experiences, my own development perspective and the results presented in this excellent meeting, the research requirements for this zone. I will not be comprehensive, but cover only those topics which I feel to have significant relevance to the development of the zone.
The World Bank's involvement in livestock development in tsetse-affected areas dates mostly from the last decade. Out of a total of US$1.8 billion World Bank funding for livestock development in Sub-Saharan Africa, an estimated US$300 million was disbursed or is committed to livestock development in the tsetse-infested areas of West and Central Africa. Roughly US$80 million out of this US$300 million was used for the financing of credit programmes (mainly for small holder fattening and animal traction), US$50 million for parastatal ranching, US$30 million for importation and distribution of trypanotolerant cattle, US$10 million for tsetse eradication and US$100 million for the strengthening of veterinary and livestock extension services.
1 The views expressed in this paper are the author's and should not be interpreted as reflecting World Bank views.
Overall performance of these investments has been rather disappointing; the main reasons were inappropriate macroeconomic policies, weak institutions and inadequate technological packages. Policy-wise, prices and exchange rates frequently favoured the consumer, but were not attractive to the producer and not conducive to increasing production. Institutionally, the initial emphasis was on parastatal ranching, which was envisaged as the technological catalyst for the modernization of the traditional sector. While technically reasonably successful and sometimes achieving acceptable fertility and mortality rates, these large ranches proved unsustainable because of excessive salary costs and inflexible central administration procedures incompatible with the assertive management required in livestock raising. Furthermore, the technology and means applied in these ranches were so far removed from the possibilities of the traditional sector, that they did not have the catalytic role envisaged. Technically, project performance was hampered by a lack of appropriate technology in range management and sustainable tsetse eradication and by adaptation problems of imported trypanotolerant cattle to their new environment.
The present trend in the World Bank's lending programme is to move away from ranching (parastatals and private) and trypanotolerant cattle imports and focus on strengthening government and private institutions in veterinary care and extension. Initial experience with those types of projects, for example, in Central African Republic, Senegal and Zaire, has been good; all scored IRRs over 100.
In reviewing the research and development requirements of the zone, I propose to cover (i) future tsetse challenge; (ii) land use in the tsetse-affected zone; (iii) the requirements of present research and development priorities and the call for the development of regional strategies.
Future scope of the tsetse problem
We observe, and this observation is confirmed in this meeting, a significant reduction in West Africa of the savanna type of tsetse flies (Glossina morsitans and G. fusca). This reduction is a result of habitat destruction caused by the population influx from the overpopulated Sahelian and Coastal zones. Furthermore, impressive progress has been made over the last decade on the development of new control methods (impregnated screens and traps, alone, or in combination with sterile males and chemoprophylaxis) for the riverine Palpalis group. These two developments together indicate that in many West African areas, a significant reduction of the tsetse pressure is in sight. For these areas it would be extremely useful to have more precise projections on the medium-term fly pressure to better define and justify the use of scarce research and development funds.
On the other hand, it is clear that the progressive incursion of trypanosensitive livestock into tsetse-affected areas, as we are observing in Central Africa, increases the fly pressure in those areas. Furthermore, many areas in Central and Southern Africa still have such a low population density, that a fly reduction because of habitat destruction is still far away. A continuous effort in tsetse and trypanosomiasis research seems therefore justified, but the rapidly changing picture might require a reassessment of present research and development priorities and especially the development of regional strategies.
Land use in the tsetse-affected zone
Introduction
The soils of the tsetse-infested tropical lowlands are low in fertility, especially in nitrogen and phosphorus. They produce large quantities of biomass, but which are extremely low in nitrogen, particularly in the dry season. This quality problem is exacerbated by a relative lack of browse plants. A mixed-farming system relying partly on the natural vegetation for livestock feed and partly on crop residues with forage legumes to increase plant and animal nitrogen would address these constraints.
The dominant focus of past research and development activities in this zone has been on increasing the yield per hectare rather than on improving the return per man day or dollar invested. However, in the land-abundant but labour - and capital-scarce situation of the tsetse-infested areas, farmers prefer to cultivate additional land rather than to invest labour and capital in maintaining soil fertility or practice land conservation. The increased use of manure or fertilizer which are labour-intensive and focus on yield increase per hectare has met with only scant success in Bank-funded projects in the tsetse-infested areas and their adoption in this zone might be still far away. On the other hand, animal traction to increase the efficiency of labour and expand the area cultivated fits in well and is being introduced successfully in a number of Bank-funded projects, especially where a cash crop makes the introduction financially viable. The better management of the natural vegetation is also not very labour or capital intensive and would have a good chance of adoption. Improved grazing management is economically the most attractive solution as shown by the Avetonou work presented in this workshop and confirmed by Bank-funded ranching projects, for example, in Cameroon and Congo.
Natural vegetation
Research on better management of the natural vegetation is also important from the ecological viewpoint. If not properly used, the sub-humid rangelands, with their low soil fertility and very fragile perennial vegetation, degrade much more easily and are much more difficult to restore than, for example, the Sahelian vegetation. Even with the present low livestock and human density, we see that important areas in the sub-humid zone are already rapidly degrading, because of massive weed invasion or bush encroachment. The inadequacy of the prevailing land use and land tenure systems, the weakness of present administrative structures to adequately control land use and the lack of adequate technical packages facilitating sustainable land use are the major reasons for this ecological degradation. Research to develop sustainable rangeland utilization and weed-control technologies therefore need to accompany any research and development effort aimed at increasing the cattle population of the tropical lowlands.
Forages
The main agricultural crops (root crops, maize) do not yield significant quantities of high quality by-products; the high quality by-products which do exist (groundnut and cowpea hay, for example) are difficult to conserve in this humid environment. Strategic supplementation of the high fiber, low protein, natural dry-season grazing with forage legumes, thus is an important means of livestock improvement in the tsetse-affected zone. ILCA's sub-humid group has produced promising results with fodder banks and intercropping of cereals and forage legumes. Both technologies have low labour and capital requirements and could make a positive contribution to soil fertility and hence to land-use sustainability. These technologies need now to be tested in development projects outside the close control and supervision of ILCA scientists. The possibility has been created in several Bank-funded projects (for example, Central African Republic, Cameroon and Nigeria).
The introduction of better range management and fodder banks is only possible if land tenure is secured. Although extremely complex, the future development of the tsetse-infested areas will depend to a large extent on the land tenure system which will evolve and we have to tackle this problem. Although still of a pilot nature, the introduction of improved security of land tenure is becoming more important in Bank-funded projects in this area. The model presently being discussed for a number of Bank-funded projects, combines individual land ownership for crops or forages with group ownership of the natural range. This model strongly focusses on crop/livestock integration, fits the specific requirements of the technologies proposed earlier and coincides with the models proposed in this workshop. In these pilot efforts, land tenure is as far as possible based on traditional systems, as we feel that traditional structures are more reliable and stronger in enforcing rational land use than the public administration. The key question that socio-economic research needs to address in this context is how to identify and adapt these traditional tenure systems and how to assure that they are strong enough.
Trypanosensitive breeds
Chemoprophylaxis
Over the last decade, an estimated ten million zebu cattle have progressively entered the sub-humid savannas and in some countries the entire livestock industry depends on trypanosensitive breeds kept under a low-to-medium fly challenge. These production systems rely heavily on the use of chemoprophylactic and chemotherapeutic drugs, as proven by the high percentage (frequently over 50%) that trypanocidal drugs constitute of total drug sales in these countries. These drugs are frequently sold through black market channels and handled by the herders themselves; official veterinary services are increasingly incapable of providing the required services because of lack of funding for operating expenses. The improvement of drug availability is therefore an important feature of the more recent Bank-funded livestock projects (Central African Republic, Chad and Guinea).
In pursuing a certain liberalization of drug sales, the danger of drug resistance must be clearly recognized. Experience shows, however, that liberalization of drug sales and administration, combined with a strong producers training programme on how to use these drugs is preferable to restrictive sales and distribution regulations. Control combined with inadequate distribution induces scarcity and scarcity leads progressively to illegal drug use (trypanocidal drugs are a question of life or death in tsetse infested areas), which poses a greater danger of creating drug resistance than would a more liberal drug sales policy, underpinned with a sound producer training programme and an effective research and monitoring programme. I therefore fully agree with Prof. Ilemobade's workshop recommendations for more research on drug resistance and would recommend specific work to determine: (a) the present extent of drug resistance; (b) the dynamics (from his presentation it appears that drug resistance was already reported in the early 1960s but still has not emerged as a major problem); and (c) the specific conditions which would trigger resistance. Such research would be a major support to ongoing development actions.
Other diseases
An increased research effort is needed in streptocicosis, as already stressed by Dr. Ferguson in his presentation. With an increased, incursion of zebus into more humid areas and a reduction of the tsetse challenge as a real future possibility, this disease acquires dominant importance and would prove as much a constraint to the introduction of zebus and especially exotic breeds, as trypanosomiasis. For example, streptocicosis is already cited as the major problem by producers in tsetse-cleared areas in Nigeria and Cameroon. Except for the indirect control methods (e.g. Pour On) described by Dr. Ferguson in his paper and the work on control methods by the IEMVT network, it appears that at present progress in tsetse control is significantly ahead of streptocicosis control and that a reassessment of priorities is necessary.
Screens and traps
The development of the impregnated screens and traps, eventually combined with sterile male releases and with chemoprophylaxis, is undoubtedly the most exciting recent development in tsetse control. The enhancement of the efficiency and effective radius of these screens through the use of easy-to-manage artificial attractants seems to be the main technical problem remaining. From the development point of view, we have little experience on how to get local producers to participate in the cost and management of these screens. We should aim for having the local population take full responsibility for the fabrication, placement and maintenance of the screens. This aspect is presently being tested in a number of Bank-funded projects and is of key importance if a sustainable system is to be developed.
Genetic differences
Finally, the work presented in this meeting on genetic differences in trypanotolerance within and between trypanosensitive breeds needs to be further explored. Drs. Murray and Njogu's presentations regarding the differences in trypanosensitivity between Orma and Galana Boran cattle gives an indication of what might lie ahead. Several cattle populations in West Africa have evolved under a permanent tsetse challenge and might show similar differences in trypanotolerant a better characterization and understanding of the scope of these differences would greatly contribute to the more efficient production of zebu breeds in tsetse-affected areas. Research to enhance trypanotolerance through genetic improvement, including the use of innovative methods like genetic engineering, might be especially applicable here.
Trypanotolerant livestock
Economic rationale
With trypanosensitive breeds increasingly populating tsetse-infested areas on a permanent basis and increasing prospects of tsetse control in the indigenous areas of trypanotolerant cattle in West Africa, I feel that the ATLN first of all needs to provide an economic rationale for these breeds beyond their trypanotolerant characteristics. My personal feeling is that the trypanotolerant breeds, with their proven high productivity, their general disease resistance and their positive response to improved conditions, will remain a key factor for the livestock development of African tropical lowlands.
An increased use of trypanotolerant cattle is presently constrained by their limited population size. The present population of 10 million head of trypanotolerant cattle is far below the potential carrying capacity of the tsetse zone of 34 million head calculated by Dr. Tacher in this meeting, or 110 million head estimated by FAO. Indeed, the Bank's major involvement with trypanotolerant cattle has been in financing multiplication centres and the importation of these breeds to alleviate this scarcity in particular countries (e.g. Nigeria). Measures aimed at achieving a more rational use of the existing trypanotolerant population, or at enhancing their reproductive performance, seem therefore to deserve a high priority.
A comprehensive technical and economic evaluation to define the optimal conditions for trypanotolerant livestock would be a first step in achieving a better use of the existing population. This was the initial raison d'etre of the ATLN with its matrix of situations varying in tsetse challenge, management system, breed and nutritional conditions. The excellent information forthcoming from the Network on the technical side needs now to be complemented with detailed economic evaluations. Such economic evaluations ideally would compare not only the economic returns of specific interventions as proposed in this workshop, but would also include a comprehensive analysis of each individual situation in terms of economic revenue, as presented in this meeting by Mr. Itty for one situation in Kenya. This comprehensive economic analysis would provide a unique data base for development planners, who now frequently have to plan interventions without basic input/output relations.
Improved utilization also implies that the production potential of the trypanotolerant breeds is fully exploited. Thus, attention should not only be directed to meat production, as has been the custom in the past, but should include milk and draught production. This diversification is extremely important. Present meat export subsidy policies of the EEC constitute a real danger to indigenous livestock industries in the coastal areas of West Africa. Milk production results from The Gambia, presented in this workshop by Dr. Agyemang, are therefore very important as they show that trypanotolerant cattle can provide additional sources of revenue and therefore provide overall rural development. Although the humid tropics seem to have no comparative advantage in producing milk, the production of small quantities of fresh milk for direct sale can well fill a special niche, as shown in The Gambia. I feel therefore that the N'Dama milk story needs to be vigorously pursued, especially under higher challenge levels and the effect of chemoprophylaxis and nutritional interventions on the production of milk investigated. Similarly, animal traction is seen increasingly as a key step in agricultural development and is progressively being introduced in tsetse-affected areas. As in the case of milk and meat production, trypanosome load seems to be an important factor affecting work output of trypanotolerant breeds. Therefore effects of chemoprophylaxis and nutritional interventions on work output and on their economic returns also need to be tested, as the Network initiated in Kenya.
Reproductive Performance
Poor reproductive performance is one of the main factors constraining increased use of trypanotolerant breeds. Present N'Dama populations under village conditions have been characterized by low calving rates, late age at first calving and long calving intervals. As indicated before, we have spent tens of millions of dollars on multiplication centers and importations of trypanotolerant cattle with disappointing results. Other ways of improving the supply of trypanotolerant cattle need to be developed. I therefore fully endorse the proposed programme of the ATLN to better understand the reproductive cycle and would encourage the Network also to look at other means of enhancing fertility and multiplication rates, for instance the possibilities of embryo transplants.
The tsetse-infested savannas are Africa's only remaining land resource with good physical potential. However, the ecology of the zone is extremely fragile and sustainable mixed-farming systems, supported by more appropriate land tenure systems, need to be urgently developed. -With a decreasing tsetse challenge in many areas, livestock production in these areas is increasingly being based on trypanosensitive Zebus kept under chemoprophylaxis, supported by other control methods like traps and screens and the sterile male technique. The increased use of trypanocidal drugs by non-professionals linked with this development, requires careful producer training and monitoring to avoid chemo-resistance. For the trypanotolerant breeds, emphasis should be on a more rational use of the existing population, not only in meat production but especially in milk and traction and on a concerted effort to find ways of enhancing their reproductive efficiency.
