Incidence of animal diseases and their current and future impacts on crop-livestock systems in West africa

Abstract

Animal diseases have a major impact on crop-livestock systems in West Africa. The productivity of all crop-livestock systems is limited both by the direct effects of overt disease and by strategies that are adopted to mitigate disease risk. Epidemic diseases require substantial expenditures to limit their spread, and so protect productivity, incomes and market opportunities. Endemic diseases, either directly or indirectly transmitted, decrease productivity, restrict production opportunities and have substantial control costs. Zoonotic and food-borne infections have important impacts on human health, livestock productivity and market opportunities. Current climatic, demographic and other socio-economic trends are changing the patterns of livestock diseases in West Africa. This is evidenced by changes in tsetse challenge and trypanosomosis risk at the margins of tsetse distribution. An increase in future demand for livestock products will lead to a greater intensification of livestock production. Four effects are likely: increased occurrence of new or emerging diseases; an increase in diseases of intensification; persistence and enhanced transmission of currently uncontrolled infectious diseases; and a greater threat of food-borne infections and residues. The current expansion of intensified livestock production and marketing in peri-urban areas, particularly the expansion of short-cycle poultry and small ruminant production, will continue. In addition, increased demand for milk in urban areas will lead to rapid expansion of formal and informal milk markets. Particular attention will need to be paid to risk assessment in these systems to protect food safety while ensuring market access to the poor and vulnerable. To adapt to these changing disease circumstances, animal health services will need to be more accessible, affordable, acceptable and sustainable. Currently animal health service delivery varies greatly across countries in West Africa with a general overall decline in the effectiveness of animal health services in recent years. Improving this situation will require targeting public-sector activities to essential public-good functions and allowing the private sector to play a greater but more carefully evaluated role in service delivery. In improving animal health service delivery, the public sector needs to be more proactive in enhancing poverty alleviation. Livestock are particularly important to poor people as a way of securing assets, as providers of marketable products and as a method for increasing productivity and income to escape the poverty trap. Disease control efforts need to focus on these poverty-alleviation pathways. Livestock diseases pose a great threat to efforts to enhance livelihoods in crop-livestock systems, principally through their many effects on crop and livestock production and by regulations that can limit market opportunities. Overcoming these losses and threats will require developing more responsive policies and institutions and adapting disease control and food safety methods that enhance their adoption and impact on farms, minimising consumer risk and maximising market opportunities.