In recent years there has been a decline in donor support for livestock research and production in the developing world. Evaluation studies suggest that such activities have a mixed record of success. Failures have been ascribed to institutional weaknesses and an inability to identify farmers’ priorities. In addition, there is an increasing donor concern about the adverse environmental effects of livestock, particularly in fragile ecosystems.

Concern has been expressed that, if the decreasing support is not reversed, donor supported activities will underplay the important rôle of livestock in rural development.

There are, however, signs that many of the lessons of experience have been learned and that there is an improving understanding of the crucial part played by livestock in sustainable land-use systems and in generating cash income.

Donors are increasingly appraising livestock activities within an agro-ecological or land-use systems framework and adopting a ‘demand-led’ approach based on farmer's priorities. Past experience suggests that Government institutions should concentrate on regulatory functions and other activities unsuited to the private sector. There is, therefore, a greater willingness to involve private-sector organizations, co-operatives and non-governmental organizations. Environmental impact assessments are becoming an integral part of donor supported rural development activities.

Any increase in the levels of funding for livestock research and development will depend on the socioeconomic and environmental impact of livestock in the developing world being better understood and, wherever possible, quantified.

In spite of being the home of a significant number of the world's flocks and herds, the productivity per head and per ha of the livestock sector in sub-Saharan Africa continues to be so low that the total output does not meet the domestic demand. Indeed, there is evidence that there has been little or no increase in output of animal products in this region during the 1980s. On the other hand, the human population has increased at a rate of more than 3% per annum. This has been associated with an escalating demand for food thus adding pressure on natural resources which are already threatened.

There is therefore a need for technical innovations to increase output of livestock products to at least a level of self-sufficiency. This increase must be obtained in a manner which is consistent with protection of the environment and conservation of natural resources for sustainable performance.

In this endeavour to develop technologies to support the livestock industries, developing countries of Africa are faced with inadequate resources to carry out research programmes, addressing a multiplicity of produciton problems. Towards this end, the donor countries have contributed resources including capital goods, technical assistance, operational finance for agreed projects and manpower development. However it is important that the national scientists are involved in the conceptualization, formulation and implementation of research programmes. The donor inputs are therefore expended in execution of projects generated by the local personnel. In this connexion, it is hoped that the level of support will be increased and sustained for a reasonable period to bear impact at the farm level. However it should be noted that research alone cannot bring about increase in output of meat and milk, etc. Rather the new technology from research is one of the inputs which must be mixed with other inputs to improve production.

Constraints do not only occur in production systems. They also limit the support available from research and extension and they have serious consequences for human welfare in Africa and for the whole community of nations.

The agricultural research agendas in sub-Saharan Africa are indicating more concern for appropriate technology and interest in collaboration but support for research is declining when it is most urgently needed. Food production in sub-Saharan Africa is not keeping pace with demand and this is a cause of instability that will constrain all other attempts at development.

The effect of the constraints is most evident on the deteriorating environment which is evident in each agro-ecological zone despite the different potentials and pressures. Animal productivity is low but has the potential for substantial improvement. Misconceptions and a lack of faith in the potential for improvement are themselves constraints in the sense that they discourage donor support for research to alleviate the real problems. Opportunities for improvement have been identified in each agro-ecological zone.

There are three major categories of research institutions: national agricultural research systems, international agricultural research centres and developed country research centres. Each has its own comparative advantages and a vital rôle to play in collaboration with the others. With the limitation in research resources there is an urgent need to develop appropriate research methods and techniques that can be applied sufficiently to have impact across the whole of sub-Saharan Africa. These are particularly required in regard to food production. Research opportunities are identified in plant genotypes, animal health, animal genotypes and extension and input supply.

An important underlying concept of the paper is the observation by Dr R. Chambers that ‘poor people in developing countries hold the solution while unchanged behaviour of rich people, irrespective of place is very much part of the problem’. It is argued that it is equally important to know, and perhaps make changes, in the value systems, models of reality and cultures of those providing technical assistance (in this case the animal science community) as of those being assisted.

It is noted that so far the contribution of livestock research to increased animal production among rural smallholders has been meager. Some of the constraints in livestock research to socio-economic development are discussed under the following broad headings: some recent thoughts on science, scientists, and development, the contribution so far, context and priorities and communication.

It is concluded that the present first constraint in animal production research is relevant senior scientific leadership. It is also concluded that a positive strategy can be identified, which starts by placing more emphasis on exposing first-world scientists to the context of the third-world farmer as such an exposure is expected ultimately to lead to a change in research priorities.

In developed and developing countries livestock are very important contributors to total agricultural output. Many breeds of different species have become either extinct or nearly so. With the spread of more advanced agricultural systems to many parts of the world, specialized strains of livestock, from a greatly reduced number of breeds within a species, have been bred for specific, but widely different, environmental conditions. This has led to a dilemma in the context of the balance to be effected between conservation of the present variety of genetic resources on the one hand and the need to concentrate increasingly on a narrow range of genotypes in the interests of improved efficiency on the other hand. The paper addresses this dilemma and discusses the FAO-instigated global programme—Animal Genetic Resources — which was designed to monitor changes in animal genetic resources on a global scale with the development of legal and regulatory instruments where necessary.

The relevance of new and traditional plant breeding technologies is discussed with particular reference to the improvement of sustainable agricultural systems in difficult environments. The focus of the paper is on barley, a crop which is grown as animal food, mostly for small ruminants, on about 17 million ha in developing countries. Barley is also a typical low-input crop being grown largely in agriculturally marginal areas by risk-averse farmers. Differences in straw quality characteristics between varieties of some crops are discussed in relation to their utilization in breeding programmes using either conventional or new technologies. A greater interaction between animal scientists and plant breeders is needed to define appropriate techniques to screen for straw quality. This is considered to be essential to incorporate straw quality characteristics in breeding programmes.

Ruminant production systems in developing countries could be classified into three categories: the extensive systems, systems incorporating arable cropping and systems integrated with tree cropping. Systems have evolved in response to the agro-ecological environment, the availability and type of land, nature of cropping patterns, frequency and intensity of cropping, area of uncultivated land and animal species and animal numbers.

Smallholder livestock farmers in most developing countries appear to have adopted a mixed system that incorporates the traditional extensive system and the system that combines arable cropping with livestock. Both in Africa and in Asia, livestock production is an important component of traditional agriculture, complementing arable cropping. Livestock utilize existing food resources such as communal grazing lands which are marginal for arable cropping, crop residues and agro-industrial by-products. Besides supplying meat and milk, organic manure and draft power, livestock are an investment and an insurance against crop failure.

Crop residues and agro-industrial by-products are a major source of nutrients for ruminant livestock in developing countries, especially during periods of fodder shortage. Despite the large research effort on upgrading crop residues in recent years, there has been little improvement in the utilization of crop residues in developing countries. Reasons for this are many but include, the absence of detailed production patterns of crop residues within countries, including when and where they are produced, the difficulties of transporting and storing crop residues, inappropriate technology and the near absence of extension services.

Both in the African and Asian continents, smallholder farmers who rear livestock for supplementary income are rather reluctant to change their traditional practices, when new technologies call for extra labour, time and capital, since the methods may be too demanding in relation to the benefit produced. The more likely application of any new technology will be with larger-scale operations where benefits are clearer and sufficiently large to warrant the extra efforts.

The place of draught animal power on farms in tropical agriculture is discussed. In some areas of the world draught animal power is traditional, in others it is a relatively new technology. There are situations which fall between the two, but when thinking about resolving technical and more particularly socio-economic constraints it is often useful to be aware of these two categories. While some of the problems encountered are universal, other problems can be more specific to a particular situation or country.

In this paper some of the issues are discussed. These include the energy requirements for work, the provision of food, particularly in ‘new’ draught animal areas, the consequences of using draught cows in traditional systems, disease treatment and two examples of country specific problems. In some cases strategies to cope with these issues are available, largely as a result of research, in others it is apparent that more information is required.

Antinutritional factors in livestock foods may be defined as the substances which either by themselves, or through their metabolic products arising in the system, interfere with food utilization and affect the health and production of animals. These deleterious substances, also referred to as anti-quality factors can be divided tentatively into four groups based on their effects on livestock: (i) affecting protein utilization and depressing digestion (protease inhibitors, tannins, saponins, lectins, etc.), (ii) metal ion scavengers (oxalates, phytates, gossypol pigments, glucosinolates), (Hi) antivitamins, and (iv) those which cannot be put in the above categories (mycotoxins, mimosine, cyanogens, nitrates, alkaloids, photosensitizing agents, isoflavones, etc.). This paper discusses only those deleterious substances which are of prime concern to the farmers and scientists of developing countries. Much emphasis is given to polyphenols compounds, as this class of anti-nutritional factor is the most widespread in non-conventional foodstuffs, i.e. agroindustrial and forestry byproducts. The effective utilization of these non-conventional foods forms the main area of research in the third world countries due to shortages of conventional foods. Efforts have been made to present the current knowledge on their assay methods, effects on animals, mode of action and detoxification/detannification using physical, chemical and biotechnological approaches. Other anti-quality factors viz., mycotoxins, mimosine, cyanogens and nitrates which also cause damage to livestock in developing countries are also discussed briefly.

This paper reviews pastoral research and development perspectives generated from the southern Ethiopian rangelands during the 1980s. This system was selected as a case study of constraints in African pastoral development because the experiences from both research and development are fairly well documented and integrated. Until recently, the Boran managed a production system that was fairly typical of semi-settled, traditional pastoralism in East Africa. However, the Boran today are in a state of considerable change that has been induced primarily by a long-term decline in the per capita supply of cow's milk, the traditional dietary staple. This imbalance has resulted from steady growth in the human population in combination with density-dependent fluctuations in cattle production. Other major changes in pastoral, social and economic attitudes have occurred as a result of population pressure and exposure to the inhabitants of small towns that have emerged as a result of development of rural infrastructure since the 1970s. Overall, this pressure has led to increased instability and vulnerability of the pastoral population, but also offers new windows of opportunity for the application of technical, but especially policy-oriented, interventions. It is suggested that constraints to implementing successful development activities here lie more in the limitations of external institutions and the national economy, rather than within the Boran system. Long-term population trends, and opportunities for development interventions over the short term, will also be obscured by inter-drought cycles of cattle production that produce complex system interactions. Greater appreciation of the effects of such cycles on the social and economic behaviour of pastoralists could facilitate more effective development planning.

The types of constraint caused by disease on extensive livestock production systems are described. Various approaches by which these constraints may be identified, quantified and evaluated are proposed and the advantages and disadvantages inherent in these different approaches are discussed.

The design of sustainable intensive livestock production systems for developing countries must be judged according to their likely impact on economic, ecological, ethological and sociological issues. Economic issues to be satisfied include international competitivity in price of finished products which requires maximizing comparative advantages of available natural resources. Ecological sustainability requires that the production system will result in (i) reduced emissions of the principal greenhouse gases carbon dioxide and methane; (ii) reduced contamination of soil and water resources; (iii) an effective control of soil erosion; and (iv) self sufficiency in on-farm production of energy from renewable resources. Ethological concerns relate to potential effects of production systems on animal welfare and the safety and consumer acceptability (wholesomeness) of foods produced in such systems. Sociological acceptability requires that employment opportunities are increased, especially for women, and that the production system encourages self-reliance with minimum dependence on outside inputs.

The basic technology, designed and adapted by Convenio Interinstitucional para la Producción Pecuaria en el Valle del Rio Cauca (CIPAV) and cooperating local farmers in the Cauca Valley of Colombia, uses sugar cane, multipurpose trees and water plants as sources of biomass to provide food for a range of livestock species and fuel for the farm and the family. The chosen crops have a proven high capacity to fix atmospheric carbon dioxide and nitrogen into biomass, which is a permanent carbon reservoir (1 ha planted in sugar cane and trees is a sink for some 80 t carbon dioxide), and also a source of substrate for food and fuel. Sugar cane and trees help prevent erosion, maintain soil fertility, have well developed systems of biological pest control, require minimum synthetic chemical inputs and are easily separated into high and low fibre fractions as required for the different end uses of food for monogastric and ruminant animals and fuel.

The preferred animal species are pigs and ducks which adapt readily to the ‘non-conventional’ high-moisture food resources (mainly cane juice, tree leaves and water plants) and have a high meat : methane production ratio. They are complemented by African sheep, dual purpose (Holsteinzebu) cattle and buffaloes, managed as triple purpose animals (draught, milk and meat) and deriving most of their food from the more nutritive parts of the fibrous crop residues. All the livestock are managed in partial or total confinement to minimize environmental damage and to maximize nutrient recycling to the crops.

Fuel for the family is derived from the biodigestor which uses as substrate the excreta from the pigs; and from the sugar cane bagasse. Earthworms upgrade the fertilizer value of the excreta from the ruminant animals and produce part of the protein for the ducks.

The CIPAV model is flexible as witnessed by the increasing acceptance of many of the elements in the model by both resource-poor and entrepreneurial farmers. The biomass concept, on which the CIPAV model is based, can also be scaled up to the level of agro-industry (the biomass refinery) offering renewable alternatives to present fossil-fuel-based technologies for chemical and energy needs.

This paper reviews current knowledge on the feeding of fibrous foods to pigs. It attempts to explain why fibrous foods differ in their nutritional value by defining what constitutes ‘dietary fibre’ and by discussing aspects associated with digestion, absorption, fermentation and metabolism in the gastro-intestinal tract. Fibrous diets can contribute proportionately up to 0-3 of the energy requirements of the animal, but there are significant reductions in the digestibility of all nutrients. There is a reduction in energy intake with increase in fibre intake, and this reduces both growth and food utilization efficiency; carcasses may, however, be leaner. Sows are better able to utilize fibre than weaned or growing/ fattening pigs and there may be improvements in reproduction as well as health and welfare benefits. Nutritive values can be improved by processing and deficiencies overcome by the use of synthetic and other materials. There is considerable potential to incorporate fibrous and by-product materials into feeding strategies for pigs in developing countries, with both economic and productive advantages.

Breeding strategies for sustainable livestock production in developing countries are discussed with reference to breeding objectives in more uniform environments of temperate regions and to those in stressful and highly variable environments of the tropics. The relative importance of breeding objectives to be based not on single performance traits but also on fitness traits is discussed in relation to production efficiency. With particular reference to breeding strategies for dairy production the following aspects are referred to: assessment of scope for performance improvement; the rôle of local breeds in stressful environments; the need for potential assessment and options for breed improvement; the use of exotic breeds; and the need for comparative field performance test as part of improvement schemes.

This paper reviews the major determinants of success in World-Bank-funded livestock development projects. First, it summarizes past project results. Secondly, it analyses the main determinants of success, i.e. the appropriateness of technologies used, the adequacy of producer incentives provided and the capacity of the responsible institutions for project planning and implementation. It illustrates the importance of these factors with experiences from Bank-funded livestock projects. Finally, the paper concludes with some thoughts on trends and requirements of future livestock development and recommendations for future research.

This paper discusses results, justifications and definitions of research and extension in tropical animal production. The emphasis is on the applicability of new technologies and the interaction between research and extension. A description is given of the participants, the farming systems and of the research-extension interaction with attention to the fact that much extension is technology driven rather than problem orientated. Special issues in the livestock sector are highlighted. The diversity of farming systems implies that generalized solutions are hard to find because of technical and institutional problems. A globally decreasing resource-base implies that solutions are to be found in making the system more efficient rather than in relying on ever-increasing use of inputs though inputs per se are still important. Some research results are listed and case studies illustrate how the resource-base affects the applicability of extension messages that originate from research. The use of models is advocated to determine priorities for research or extension. Failures to find quick field applications should lead to mobilization of existing information as well as to a reorientation, improved quality and better interaction of research and extension.