In this report, the nature and strength of interactions between “Landless livestock monogastric” production systems (LLM systems) and the environment are discussed, as well as some options for mitigation. Chapter 1 presents the delineation and definition of LLM systems. A general description of LLM systems and its subsystems, the presentation of a classification system and a discussion on some past and future developments is given in Chapter 2. LLM systems are livestock systems with high animal densities, in which feed is introduced from outside the farming system. Typically LLM systems use information intensive and capital intensive technologies that can easily be transferred across the world, which explains the worldwide occurrence of these systems. Compared with other livestock production systems, animals in LLM systems have a short production cycle and thus a high turnover, and hence the capacity to rapidly adjust to changes in demand for outputs or supply of inputs. The world distribution is strongly correlated with the degree of urbanization and annual income per capita, Asia and the OECD countries having the largest share in LLM production. LLM systems are particularly prominent in areas with competitive advantages, resulting, for instance, from a well-developed infrastructure, nearby markets and a high knowledge level. Management and infrastructure requirements generate large economies of scale in LLM systems. High producing hybrid breeds are used. Animal nutrition is based on concentrates introduced from outside the farming system, so decisions on feed use are separated from those on feed production and manure utilization. Although LLM systems are increasing in all world regions, growth rates differ. Determinants are past and future developments in price ratios of inputs and outputs, infrastructure, knowledge level, and demand for products from LLM systems. In many developing countries, particularly in Asia, growth rates are high, chiefly related to general economic growth.
The nature and strength of interactions between LLM systems and the environment is given in Chapter 3. Livestock - environment interactions are caused by direct or indirect effects, either positive or negative. Indirect effects caused by LLM systems occur as a result of the production of the inputs (concentrates, fossil energy) or from the processing of outputs. Indirect effects are only briefly discussed in this report but more extensively in other reports of this study. Direct effects result from the use of inputs in LLM systems, the most important being fossil energy and concentrates. Most effects are caused by emissions from manure in the form of nitrogen (N), phosphorus (P) and various heavy metals. LLM systems can also be related to some other, strictly spoken non-environmental issues: depletion of animal genetic resources, competition between food and feed, food safety problems and issues regarding animal welfare and high consumption levels of animal products. In the following table a schematic presentation is given of the issues dealt with in this report, respectively the methodological approach used.
Table: Livestock - environment interactions dealt with in this report
|
system-wide quantification |
semi-quantitatively/case-study approach |
qualitatively |
|
- N and P excretion by animals in LLM systems and emissions occurring before manure application; - methane emission; - wastes from animal processing. |
- N and P emissions occurring after manure application to land; - fossil energy use; - heavy metals; - competition between food and feed. |
- food safety; - animal genetic resources; - associated problems: - animal welfare; - high consumption levels of livestock products. |
- 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. Nitrogen 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 use. 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, production from LLM systems seems 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 requirements of animals. Cd is a pollutant of animal feeds, introduced via feed phosphates. Compared with artificial fertilizers, animal manures contain 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 can not be made.
- Methane emissions from LLM systems are relatively insignificant, 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 very little offal and blood is washed away, while in most other countries more offal is washed away locally resulting in high water pollution levels.
- 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 ca 32% of total concentrates fed to livestock. Cereals are an important feed ingredient of these concentrates. 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, resulting locally in increased price levels of food 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 labourious 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 at present 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.
In Chapter 4 a framework for the design of technological and policy options is given, and some options are discussed. Compared with other meat and egg production systems, LLM systems are relatively efficient at animal level. However, this high efficiency at animal level coincides with various trade-offs that become visible at higher aggregation levels, for instance in fossil energy consumption, competition between food and feed, animal welfare and the use of veterinary products. When designing technological and/or policy options to mitigate environmental problems, one should always be aware of possible trade-offs like these. An essential characteristic of LLM systems is the highly concentrated production, not only attributing to high efficiency at animal level, but also to the major environmental problems related to LLM systems. Consequently, environmental problems resulting from concentrated production (for instance ammonia emission, accumulation of heavy metals, P saturated soils), the most important criterion is the emission per unit of area.
Technological options for the mitigation of negative livestock - environment interactions should generate; (1) a reduction in N, P, Cu, Zn and Cd excretion by animals per unit of product; (2) a reduction in N and P-losses from manure in stables and during storage; (3) methods that efficiently re-use energy or minerals in manure, when manure is not directly used in agriculture; or (4) a reduction in N and P losses from manure during and after application to soils. The last mentioned category is not discussed in this report, but in the report on manure management. Individual options mitigate environmental problems only to a limited extent and often lead to an increase of costs.
Current environmental policies vary enormously among countries. Policies can be divided into two categories: legislation and guidelines. Guidelines are most common. Major environmental problems related to LLM systems could be mitigated by policies that reduce the regional concentration of LLM systems, i.e. by improving the integration with arable production, aimed at better utilization of animal manure and a reduction of the use of artificial fertilizer. Direct policy options to improve this integration are confronted with major limitations on technical and economic feasibility and controllability. Therefore, indirect policies seem more promising, especially economic instruments, though these are handicapped due to non-sector specific effects.
