Senior Officer (Livestock Development Planning), Animal Production and Health Division, FAO, Rome, Italy.

LEAD Livestock, Environment and Development initiative


Industrial production of pork, poultry and (feedlot) beef and mutton is the fastest growing form of animal production. In 1996, it provided more than half the global pork and poultry (broiler) production and 10 percent of the beef and mutton production. This represented 43 percent of the total global meat production, up from 37 percent in 1991-93. Moreover, it provided more than two-thirds of the global egg supply. Geographically, the industrialized countries dominate industrial pig and poultry production accounting for 52 percent of the global industrial pork production and 58 percent of the poultry production. Asia contributes 31 percent of the world's pork production (Sere and Steinfeld, 1996).

Industrial ruminant production is concentrated in Eastern Europe, the ex-Soviet Union and in the OECD countries. Typical examples are large-scale feedlots in the USA and in the formally centrally planned economies. Industrial sheep feedlots are found in the Near East, North Africa and the USA.

The industrial production system is open both in physical and economic terms. It depends on outside supply of feed, energy and other inputs. Technology, capital and infrastructure requirements are based on large economies of scale and, because of this, production efficiency is high in terms of output per unit of feed or per man-hour, less so when measured in terms of energy units. Yet as the world's main provider of eggs, poultry meat and pork at competitive prices, it meets most of the escalating demands for low cost animal products in rapidly growing urban centres of the developing world.

Environmental challenges

Because of its open nature and many interfaces with the natural resource base, the industrial ‘bio-industry’ system signifies for many the epitome of what is wrong with animal production. The industrial scale implies large herd/flock sizes, large volumes of waste, high animal health risks, and often less attention to animal welfare. It has multiple opportunities to dump its waste products without accounting for the environmental costs. The biggest problem, however, is the over-concentration of animals in areas of high human population density with little viable opportunities to utilize waste products on land. The biggest challenge is to establish policies and identify technologies that will help in bringing animal waste in line with the assimilative capacities of land.

Status quo of interactions

The industrial system acts directly on land, water, air and biodiversity through the emission of animal waste, use of fossil fuels and substitution of animal genetic resources. In addition, it affects the golbal land base indirectly, through its effects on the arable land to satisfy its feed concentrate requirements. Ammonia emissions from manure storage and application lead to localized acid rain and ailing forests, for example in European countries. Also, the industrial system requires the use of uniform animals of similar genetic composition. This contributes to within-breed erosion of domestic animal diversity.

Animal Waste

Land, water and air are the environmental components mostly affected by the concentration of animals and waste production. Manure is the main agent having effect, mostly during storage and after application on the land. Pigs and poultry excrete some 65 to 70 percent, respectively, of their nitrogen and phosphate intake. Nitrogen, under aerobic conditions, can evaporate in the form of ammonia with toxic, eutrophic and acidifying effects on eco-systems (Wilson and Skeffington, 1994). A greenhouse gas, nitrous oxide (N2O) is formed as part of the denitrification process with particularly harmful effects on the environment. Nitrates are leached into the groundwater posing human health hazards, and run-off and leaching of nitrogen directly lead to eutrophication and bio-diversity loss in surface waters and connected ecosystems. Phosphorus, on the other hand, is rather stable in the soil, but, when P saturation is reached after long-term high level application of manure, leaching occurs and this also causes eutrophication.

Ammonia and other nitrogenous gases result from the digestion of protein, part of which is lost in manure and urine. Growing pigs, for example, excrete 70 percent of the protein in feed while beef cattle excrete 80 to 90 percent and broiler chickens 55 percent (Jongbloed and Lenis, 1992). Ammonia, in high concentrations in the air, can have a direct effect on plant growth, by damaging leaf absorption capacities but its indirect effect on soil chemistry is even more important. Ammonia acidifies the soil, interferes with the absorption of other essential plant elements, particularly in nitrogen-poor ecosystems such as forests. Livestock production is a major source of ammonia emissions in the industrial world. For example, of the 208,000 tons of ammonia emitted in the Netherlands in 1993, 181,000 tons was estimated to come from manure (Heij, 1995). This was about 55 percent of the total acid deposits in the Netherlands, industry and traffic being other important contributors.

The various forms of nitrogen losses lead to much reduced levels available for crop nutrition. Plant uptake and use depend on a series of other factors such as species, climatic and soil conditions. According to Bos and de Wit (1996), 20, 50 and 44 percent of the nitrogen excreted by pigs, broilers and laying hens are lost to the atmosphere as NH3. Because of its different chemical properties, phosphorus losses are insignificant because phosphorus is not very mobile in the soil.

The amount of N, P, K and other nutrients available to the crop within the soil determine the fertilizer value of manure. Further significant losses may occur depending on the type of stable and manure management system ( Safeley et al., 1992) and thus define the direct environmental impact. Substantial nitrogen and phosphorus losses also occur when manure is applied on the land. The spreading of manure directly on the land can lead to nitrogen leaching into water as nitrates and contamination of surface waters. This in turn leads to high algae growth, eutrophication and, as a result damages aquatic ecosystems. Not all soils are equally susceptible to nutrient loading and contamination. Sandy soils with low cation exchange capacity and, consequently, poor retention characteristics and high run-off , are particularly at risk.

Heavy metals

Copper and zinc, which are essential minerals in animal nutrition, are deliberately added to concentrate feed whereas other heavy metals, in particular cadmium, are introduced via feed phosphates. Only 5 to 15 percent of metal additives are absorbed by animals, the rest is excreted. Soils, on which poultry and pig manure are continuously applied at high rates, accumulate heavy metals, jeopardizing the good functioning of soil, contaminating crops and posing human health risks (Conway and Pretty, 1991)

Fossil fuels

The industrial system is a poor converter of fossil energy. Fossil energy is a major input of intensive livestock production systems, mainly indirectly for the production of feed . Brand and Melman (1993) show in case studies that, typically, feed accounts for 70 to 75 percent of the total energy input except for veal production where it is almost 90 percent. Energy output for livestock products comprises food and non-food items. Southwell and Rothwell (1977) calculated output/input ratios of 0. 38, 0. 11 and 0. 32 for pork, poultry and eggs respectively, considering fossil energy only.

A large portion of non-food energy output is in the form of manure and the potential for recovery of this energy in the form of methane has greatly increased in recent years. The heavy concentration of animals in certain regions, particularly of pigs and poultry, has given rise to the development of large- scale processing for use elsewhere. Most problems lie in high energy expenditure for drying and for transport.


The industrial system has a threefold effect on species wealth through:

Environmental benefits of industrial production systems

First, the rapid development of ‘modern’ industrial pig and poultry systems helps to reduce the total feed requirements of the global livestock sector to meet a given demand. It may therefore alleviate pressures for deforestation and degradation of rangelands, such as is happening in parts of Latin America and Asia, thus saving land and preserving biodiversity. Second, the feed-saving technologies developed for this system can be effective at any scale and therefore can be successfully transferred to mixed farming systems. The same holds true for waste prevention and treatment technologies which have been developed following regulations applied mainly to the industrial system. There, the resource-saving and waste management technologies generated by the industrial systems bring benefits to the sector as a whole.

Driving forces in industrial production

Population growth, rising income and urbanization are the fundamental driving forces determining growth of industrial livestock production. Globally, industrial animal production is the fastest growing sector, with over 4 and 5 percent growth per year in pork and broiler production, respectively. The Annual growth for eggs is 3.8 percent and for mutton and beef 2.5 percent. Driven by rising incomes and rapid urbanization, Asia experienced a staggering growth of 9 percent per year in industrial pig and poultry production over the last decade, trailed by Latin America with a strong growth in poultry.

As shown above, it is not industrial production per se which creates environmental problems but the fact that production units tend to concentrate in certain areas. The reasons are the following:


In the past, industrial and intensive mixed farming systems have benefited from policy distortions and the absence of regulations or their enforcement and, in many cases, this vacuum has given this system a competitive edge over land-based systems. Furthermore, some policies have misdirected resource use and encouraged the development of technologies which are inefficient outside the distorted context. In the EU, for example, high domestic prices for beef, pork and milk have benefited industrial production. In the Near East, small ruminant feedlots are heavily dependent on subsidized feed, and this has encouraged inefficient feed use. Likewise, in the former centrally planned economies, feedlots were based on heavily subsidized feed grain and on subsidized fuel and transport. In many developing countries, there are not only direct subsidies on feed but also on energy. As energy is a major direct and indirect cost item in industrial production systems, economy-wide policies often tend to favour industrial production over grazing systems and mixed farming.

Finally, in practically no country in the world, is the industrial system charged with the full environmental costs of production. It appears that societies prefer the cheap supply of animal products over the functions of the ecosystems concerned. Self-sufficiency in animal products and supply of high-value food commodities to urban populations seem to be overriding policy objectives, particularly in developing countries.

Technology and policy options

In the developed world, the pollution of land, water and air has raised acute awareness of the environmental problems associated with industrial livestock production. This has, in many cases, triggered the establishment of policies and regulatory measures that address these problems. To the contrary, the absence of regulations and their enforcement, together with a surge in demand and a continued indifference about growing environmental hazards in the developing countries call for immediate action. The challenge is to identify and mix the appropriate technologies and policies that suit local circumstances.

Policies and regulations


The above policies have been accompanied by the introduction of a wide range of new techniques. Because of the commercial and demand-driven nature of the industrial system, development and transfer of technologies are usually not a problem. A whole range of technologies exists that could alleviate the environmental burden created by this system and seek improvement in two areas:

  1. Reduction of nitrogen and phosphate excretion by improving feed utilization can be achieved through:

  2. Reduce the emission from manure storage and during application. Nutrient losses from manure in stables and during storage can be reduced through improved collection and storage techniques. In animal buildings, manure is stored either under a solid floor, under a slatted floor, or within a housing system with litter. A large part of ammonia emissions comes from the manure surface in storage, either under the slatted floor or in open tanks. The main focus has to be on reducing nitrogen losses, most of which are in the form of ammonia from the manure surface. Possibilities are:

Methods that efficiently re-use energy and nutrients in manure in cases where manure is not directly used for agriculture. Biogas plants of all sizes and different levels of sophistication exist. They not only recover the energy contained in manure but also eliminate most of the animal and human health problems associated with micro-biological contamination by micro-organisms. Other methods of controlling the waste load are purifying and drying the manure; reducing nutrient losses during and after application of manure on soils. Injection or swad application of manure into the subsoil and appropriate timing significantly reduces losses. Nitrification inhibitors can be added to the slurry to decrease leaching from the soil under wet conditions.

Large-scale manure processing is possible where intensive production is concentrated in certain zones but that is often not viable economically. The efficient use of manure for feed and energy production requires high capital investments which often cannot be borne by individual farmers.

Recycling manure by feeding it back to livestock, including fish (Müller, 1980) is practised only on a limited scale. In addition to widespread reluctance to use manure as feed, mainly originating from fear of health hazards, most types of manure have a low nutritive value with the exception of poultry manure which is of a reasonable quality. In intensive production systems with large amounts of collectable manure, cheaper feeds are also available, while in production systems where utilization of low quality feeds is common, high collection and opportunity costs (manure as fertilizer or fuel) prohibit the use of manure as feed.


Stricter environmental standards and corresponding incentives to a better balanced land and animal distribution could be a powerful tool to promote rural and agricultural development: prices for animal products would increase, providing land-based production incentives to intensify; and the development would be more decentralized, creating employment and marketing opportunities outside the large urban centres. Such a process will have to be monitored carefully so as not to lose the technological edge by removing economies of scale and functioning infrastructure and needs to be seen in a regional development context. As has been shown, the industrial system obtains its advantage in efficiency through a combination of factors:

This has important implications for the future. The analysis shows that most expansion and productivity growth will have to be sustained through the provision of concentrate feed, which normally would require additional land. The establishment of proper controls for the industrial system would then lead to intensifying livestock production through better feed conversions, and intensifying crop production aiming at higher yields. Both will reduce the land requirements for given volumes of final products and alleviate pressures on habitats and biodiversity.

Following the line of argument, measures to foster biodiversity and protection of natural resources would encourage improvements in feed conversion by removing obstacles and providing incentives for a more efficient use of feed. Large opportunities lie in astute pricing of concentrate feed and in providing access to related technologies. A practical difficulty lies in the crop-country nature of measures and effects when feed is imported and international agreements will need to be found.

In conclusion, the industrial system poses a large range of environmental problems but also offers many possible solutions. The world's human population will increase from today's 5.5 billion to around 10 billion by the year 2030, i.e. almost double. With increasing incomes, urbanization and ageing populations, the world demand for animal products is likely to triple, perhaps quadruple.

Neither the grazing nor the mixed farming system, as we know it, will be able to satisfy this increase in demand. The greatest part of the additional demand will have to be supplied by the industrial type of production.

For this to happen, two requirements must be met:


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