Unlike most other livestock systems as defined in this study, LLM systems are widely spread throughout the world. Two main reasons explain this widespread occurrence:
1) Compared with other livestock systems, LLM systems are characterized by the use of relatively highly sophisticated production technologies, that can easily be transferred across the various regions of the world.2) Feed in LLM systems is largely introduced from outside the farm system, consequently, LLM systems do not have a strong link to land.
The distribution of LLM systems across the world is by definition strongly correlated with population density and annual income per capita. As a consequence, the picture is dominated by OECD countries and Asia, accounting for 52 and 31% respectively of worldwide pig production in LLM systems, and some 50 and 20% respectively on worldwide poultry production in LLM systems.
With few exceptions, LLM systems are expanding in all regions of the world, although substantial differences exist. Growth rates are especially high in countries with high economic growth, i.e. mainly in Asia. In OECD countries growth rates are much lower. These countries clearly show signs of market saturation. Other regions of the world are mostly in between these two extremes.
Expansion of LLM systems can be explained by an increase in demand for products from LLM systems and the shifts in prices of inputs and outputs. Increasing demand for products from LLM systems is related to general economic growth, which is often simultaneously accompanied by changes in input/output prices in a direction that stimulates further expansion of LLM systems. Thus, expansion of LLM systems is strongly related to economic incentives on the input side as well as on the output side. Changes in demand for products and input/output prices of LLM systems that took place in the early fifties in OECD countries are now more or less taking place in developing countries, but at a much higher pace.
Most direct environmental effects caused by LLM systems occur in the form of emissions. Most emissions are from manure during storage or after application to soils. Most harmful emissions are in various forms of nitrogen and phosphorus, either to soils, water or the atmosphere. Emissions result from the utilization of the main inputs in LLM systems: fossil energy and concentrates. Indirect environmental effects occur during the production of inputs (e.g. the production of concentrates) or during the processing of outputs. Other effects induced by LLM systems are increased competition between food and feed, contribution to genetic erosion, food safety problems and problems regarding animal welfare and consumption of livestock products.
Classification of LLM systems with respect to environmental impact is complex. The main reason for this complexity is that values of the various classification factors may vary enormously among countries, even if the production structures of these countries seem comparable. For each case (i.e. region), several classification factors will have to be considered simultaneously, and at least at more than one hierarchical level.
System-wide quantification of livestock-environment interactions in LLM systems is strongly hampered by a lack of data. Based on a number of assumptions, a system-wide quantification could be done for N and P emissions from manure before application, methane emission and wastes from processing. Emissions of N and P from manure after application to soils, fossil energy consumption and heavy metals have had to be considered in a case study approach. Competition between food and feed production was dealt with in a semi-quantitative approach, whereas food safety animal genetic resources, animal welfare and effects of consumption of livestock products on human health were considered in a qualitative way. From the assessment of livestock - environment interactions performed in Chapter 3, the following conclusions can be drawn:
- Nitrogen emissions from manure before any form of application are high: 44, 50 and 20% of N excreted by pigs, broilers and laying hens respectively are lost. Most of the N losses are harmful to the environment, mainly due to the high regional concentration of LLM systems. N-losses induce a large extra fossil energy consumption, needed for the production of artificial fertilizer with an estimated value of US$ 1,010*106 to compensate the N losses. Phosphorus emissions from manure are only calculated for pigs and amount to 3.6% of excreted P. To compensate these losses extra artificial fertilizer with a total value of US$ 14*106 has to be produced.- Substantial N and P emissions also occur after land application of manure. However, due to a wide range of determining factors, an enormous variation exists. Compared with other livestock production systems, emissions from manure produced in LLM systems may be expected to be relatively high since manure production is concentrated in a small area and consequently the manure is more or less seen as a waste, resulting in high application doses, often under unfavourable conditions.
- Fossil energy consumption by LLM systems is mainly related to concentrate utilization. Fossil energy costs per unit of feed are dependent on nature and production method of the feed ingredients and transport costs, while energy costs for the processing of feedstuffs are relatively small, except drying of wet by-products. Though fossil energy utilization calculations are fraught with difficulties and results are highly dependent on underlying assumptions, LLM production seems to be energy intensive compared to other meat and egg production systems.
- It is common practice to add Cu and Zn to feed rations via mineral mixtures, generally resulting in levels far above the animals’ requirements. Cadmium is a pollutant of animal feeds, introduced via feed phosphates. Compared with artificial fertilizers, animal manure contains high levels of Cu and Zn and low levels of Cd per kg N or P applied. Accumulation of heavy metals in soils may be expected to occur when their supply exceeds crop uptake. This might occur when pig and poultry manure is applied at high rates for a long period of time. Determining factors vary greatly across the world and general statements cannot be made.
- Methane emissions from LLM systems are relatively insignificant and mainly originating from anaerobic decomposition of animal manure.
- For the assessment of wastes from animal processing, it is relevant to distinguish between OECD countries and other countries. In OECD countries, by-products, very little offal and blood are washed away, while in most other countries most of it is wasted, resulting in high water pollution levels locally.
- Competition between food and feed occurs directly through competition between man and animals for food that is suitable for both, and indirectly through competition for land on which feed or food can be produced. In this report emphasis is on the direct form of competition. LLM systems account for 32% of total concentrates fed to livestock. Cereals are an important feed ingredient of these concentrates are cereals. In the early nineties, some 40% of the world cereal harvest was fed to livestock. About a quarter of total cereals used for livestock is fed in developing countries. The use of cereals in animal feeds is expected to increase in the future, especially in developing countries, accompanied locally by a replacement of food grain by feed grain. Despite these facts, assessing the significance of competition between food and feed is a complex matter: agriculture in principle produces enough food calories to meet the world food requirements, but large surpluses and deficits exist at regional, national and sub-national levels, since food production, purchasing power and consumption are not distributed evenly among the world population. This uneven distribution is much more related to cultural, socio-economic and political factors, rather than to livestock production.
- Feed additives rarely cause food safety problems. The complexity and scale of LLM systems, however, is likely to induce high disease pressure, while the immune status of the animals is reduced, resulting in a higher dependence on veterinary products for (sub-)therapeutic use. The complexity and scale of LLM systems is also likely to induce higher risks of contamination by e.g. heavy metals or new serotypes of pathogens. Monitoring systems are generally well developed in intensive systems, but deemed to be inadequate to prevent incidents as screening for every possible contamination is highly laborious and costly.
- In the fifties and sixties global pig and poultry breeds emerged at the expense of local breeds. In developed countries many local breeds have already completely disappeared, and in developing countries many are currently at great risk. Thus, rapidly expanding LLM systems, using only a limited number of breeds may substantially contribute to genetic erosion in developing countries. The key question is whether LLM systems compete with traditional pork and poultry production systems for market shares or whether they are supplementary. This can be expected to vary between countries and in time.
- Public concern about animal welfare problems in LLM systems is increasing, particularly in OECD countries, which may affect production structures in LLM systems. Improving animal welfare in LLM systems is complicated by trade-offs. The heavy debate on the relation between (high) livestock product consumption and human health problems may also have some impact.
Major environmental problems related to LLM systems originate from concentrated production, of which the environmental impact per unit of area is the most important criterion. For worldwide problems that are not problematic because of their concentration in a small area the impact per unit of product is justified as a criterion.
When designing technological and/or policy options to mitigate environmental problems, one should avoid the introduction of trade-offs. In principle there are many technological options, which when individually implemented, mitigate environmental problems to a limited extent. They also often lead to cost increases. Major environmental problems caused by LLM systems could be mitigated by improving the integration with arable production. Direct policy options aimed at improving this integration are confronted with major technical and economic constraints and with limitations with regard to controllability. Indirect policies will then have to be adopted, e.g. price policies, but here too there are major limitations: they should be designed in such a way that the “polluter pays” principle is justified, which is a matter of high complexity.
