Livestock Advisor, Agriculture and Natural Resource Department, World Bank

LEAD Livestock, Environment and Development initiative


The interactions between livestock production and the environment are complex. Understanding the physical mechanisms, with which livestock improve or degrade the global natural resource base of land, air, water and bio-diversity is clearly important; however, human actions and activities, which make livestock behave the way they do, are much more important. In this Conference on Livestock and the Environment, it would therefore be incomplete to look only at physical interactions, such as the effect of stocking rate on the vegetation, or quality of feed on methane emission and global warming. A broader framework is required, which links human behavior and biological phenomena, such as grazing behavior and waste emission, into comprehensive models.

This presentation seeks to sketch that broader framework. It will first describe the two conceptual models used in the Livestock-Environment Study, then use these models to describe general principles regarding livestock-environment interactions, within and beyond production systems, and how future demand will affect the dynamics of those interactions. To provide the overall context, the paper will then link the objectives and scope of the Study with the same two conceptual models. The following papers in this Conference will focus on particular production systems, or describe cases within production systems with particular interesting policy-technology interactions.

A conceptual framework for livestock-environment interactions.

The conceptual framework used for the Study, which will also be followed in several presentations in this Conference, consists of a combination of two well known models: the Pressure (driving force)-State-Response (PSR) model, developed by OECD (1996), and the induced innovation model by Ruttan and Hayami (1985). These models are complementary. The PSR model links the pressure from livestock production (as resulting from demand and the socio-political environment of production), to changes in the state of the natural resources. These changes then may cause a response of the society. This response, mostly implemented through policy and institutional changes, in turn changes the relative prices or availability of inputs, inducing the use of alternative technology. For example, demand for pork and import protection of pork production, may lead to excessive production of manure and waste, which may lead to water pollution, ammonia emission and acid rains, and loss of bio-diversity. This may cause society to abolish the import protection and impose taxation on the amount of waste produced. This, in turn may lead to the introduction of technologies, such as additives and genetic improvement for better feed conversion, etc.thus reducing the amount of waste. In its simplest form, the model (integrating the PSR and induced innovation models) would be like this:

1 Paper based on De Haan et al. (1997)

This conceptual model is now being used by several international and national agencies.

Pressure: demand, policies and institutions

Steinfeld et al (1997) describe the expected dramatic increase in demand for livestock products, and the stagnant, but still substantial, demand for non-food services of livestock. This paper will concentrate on the policy and institutional conditions, which affect demand or exacerbate the way demand for livestock products interact with the environment.

There are four types of policy or institutional conditions, which might affect that pressure (Young, 1996). They are:

State: within and beyond production systems.

Production systems: the main arena for livestock-environment interaction

Most livestock-environment interactions are production systems specific. Production systems are therefore used in this Study as the main physical arenas in which livestock - environment interactions occur. Production systems are agro-ecological systems, where similar combinations of market opportunities and resource endowment lead to similar production modes. For this Study the world's livestock production is classified according to three production systems, mainly based on criteria of amount of feed produced within the own system:

Currently, the mixed farming system produces globally more than half the meat, and 90 percent of the milk. Most of the remaining production comes from the industrial system.

Any classification simplifies, is reductionist, and is therefore open to criticism. For example, this classification does not account for the interactions between systems, such as occurs intensively between the grazing and the mixed farming and crop systems, for example in the Sahel.

Principles of Livestock-Environment interactions (impact domains) within production systems.

The grazing and mixed farming systems are, in principle, rather closed systems, where the waste produced is used again within the same system. This means that there is a direct incentive for the producer to utilize this waste in an environmentally sustainable fashion. Environmental problems occur, when these incentives disappear. This is the case, when the system opens up (or as the economists would say; “when externalities occur”), for example, when collective grazing rights deteriorate and communal grazing areas become open access areas. It is also the case, when outside pressures strongly disturb the balance between nutrient inputs and outputs. These pressures can come from a growing population, as is the case in Central Africa, where the nutrient outflow is so strong that serious nutrient imbalances occur. This is called the involution of the system. It is also the case in the developed world, where the pressure from feed and fertilizer subsidies causes the use of excessive amounts of nitrogen fertilizer and feed. This leads to nutrient loading of soil and water.

The industrial system is considered by many the antithesis of an environmentally benign system. It is an open system, where most of the waste produced in the enterprise can not be used within the same system. Without incentives and regulations, large amounts of waste (the industrial system produces about 8 billion tons of waste per year) would be emitted outside the system. However, industrial production also has advantages, most notably, in its efficient use of feed grains. In doing so, it might relieve some environmental pressure from other systems, and so save fragile eco-systems, which otherwise would be affected by the grazing or mixed systems.

Impact domains beyond production systems: Global overlays

There are a number of livestock-environment interactions, which go beyond the confines of a production system. They are:

Response: differential growth of the different production systems.

Based on past trends and future demands, the Study projects a strong expansion of the industrial system. If that is true, this would have significant impacts on global natural resources.

Some growth is to be expected in the grazing system, but this will be slow, as it has been in the past. Current trends show good grazing land being taken over by crops and urbanization. In effect, in the OECD countries and in Asia, the area of grassland is declining. In addition, there is no significant breakthrough at the horizon, which would change the yield or feeding value of tropical grasses.

Nor can the mixed farming system be expected to supply the major part of the increased demand. In this system the growing pressure for economies of scale and from increasing market opportunities, would lead to the specialization of production. Most likely, the major growth would therefore have to come from the industrial system, and mostly from intensive crop-based pig and poultry production, as already shown by the past trends. This would imply that livestock production moves from a closed to an open production system with less opportunities and incentives to recycle its own “waste products”. The strong growth of the industrial system would for this reason have mostly negative impacts on the natural resource base (nutrient loading, soil losses, air quality and losses in domestic and wild bio-diversity).

Countervailing forces to these trends would be increasing grain prices, a much stricter internalization of the environmental costs in the producer price, or increased concern for animal welfare. A quantum leap in tropical livestock production, which could also significantly alter these projections, would be a major breakthrough in ruminant nutrition, for example through the identification of micro-organisms, able to break down the crude fiber in the rumen of tropical forages.

However, whatever happens, there will be increased pressure by livestock production on the natural resource base in all production systems. Over the next decades, producers, livestock technicians, environmentalists, policy makers and project implementors, therefore face a considerable task to get the policy framework right, so that environmentally the most friendly technologies are being used to satisfy the growing demand.

The challenge: the identification of the appropriate policies.

General principles

A number of general principles deserve to be mentioned first (Young, 1996). The first general principle concerns the approach. Environmental impacts from pressure by livestock can be reduced by regulating and prohibiting them, or by reducing the underlying causes of the problem. The latter is more effective, and as it removes the incentive to cause the problem, and therefore requires less monitoring. Thus, for nomadic herders in Africa, alternative employment generation, good pricing policies and strengthening the responsibility for the stewardship of their land, through reinforcement of their traditional grazing rights, is more effective than trying to control, through outside authorities, the animal stocking rate.

The second general principle concerns the targeting. A key lesson from the past is that social objectives (i.e. increasing farmers income) should not be coupled to mechanisms which determine market prices. For example, the input subsidies and price supports in the EU have caused the concentration of intensive units in several OECD countries. It would be better to provide direct income support.

The third general principle is that a mixture of instruments is almost always required.

Specific instruments

Some of the key aspects of each policy instrument are described below. Young (1996) and the later papers provide more information.

This study: an application of the PSR and induced innovation models.

The Livestock-Environment Study, the main background document of this Conference, can be seen as an application of the PSR and induced innovation models. The Study responded directly to a concern of society, in seeking a more objective assessment of livestock-environment impacts and the identification of policies and technologies, which mitigate the negative and enhance the positive impacts of livestock. In this Study, the focus is on the environmental impacts of livestock development only. Other issues, perceived to be problem areas in relation to livestock development are not covered. Thus, the Study accepts the consumption level as a given (indicating that quite clearly in some parts of the world. consumption level are high and can be reduced, but that in most parts, consumption levels are going to rise). It also does not cover animal welfare.


This Livestock-Environment work is at a crucial point. If the projections and conclusions in the Study are correct, everybody involved in livestock development and the environment, i.e., producers, livestock specialists and environmentalists, policy makers and scientists, face a major challenge. We hope that at the end of this Conference, a consensus will have been created on the nature and severity of this challenge and on the need for and the direction of future actions to address that challenge. The initiative, with its widespread participation and global and comprehensive focus, can ensure that implementable actions can be readily translated into on-the-ground activities.


de Haan. C, H. Steinfeld and H. Blackburn (1997). Livestock and the Environment: Finding a Balance: Wrenmedia, Suffolk, U.K.

Hayami Y. and Ruttan (1985). Agricultural Development: An international perspective. John Hopkins Press, Baltimore.

OECD(1996). Developing Agro-Environmental Indicators: June 1996. Organization for Economic Cooperation and Development, Paris.

Steinfeld H., C. de Haan and H. Blackburn (1997). Livestock and the Environment: Issues and Options. Wrenmedia, Suffolk, U.K.

Young M.D. (1996). Maintaining Harmony: Equitable and efficient means to minimize negative effects of livestock on the environment. Paper presented in the Workshop on Livestock and the Environment, September 1995. World Bank Washington D.C.