![]() | CERES No. 122 (FAO Ceres, 1988, 50 p.) |
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by Engelhard Boehncke
The problems of animal production in Europe today are as follows: overproduction; the use of a great deal of imported feedstuffs; intensive housing systems with a tremendous local and regional concentration of livestock; and animal diseases. Consumers are becoming more and more critical of factory farming.
On the above, most experts agree. However there is nothing but disagreement about what to do.
Desperate attempts to find solutions only bring about new difficulties as governments produce endless regulations to limit overproduction and environmental damage. Politicians in the agricultural sector dismiss organic farming in the belief that ecological agriculture is not economically sound - but they do not do all the sums. They do not count the costs of physically storing surplus milk powder and refrigerating butter and meat, nor do they consider the costs of repairing damaged ecosystems.
This article will attempt to describe the special problems of modern animal production and to suggest some possible solutions in organic farming systems. Two aspects of animal husbandry, animal nutrition and animal health, will be discussed in detail.
Animal nutrition. Animal nutrition in organic farming systems is mainly based on farm-grown feed. That means that both the crop rotation and the number of animals kept must be harmonized with the conditions of the particular farm. Therefore the nutritional demands of livestock are regarded as an integral part of the farming system, the quality of animal feed assumes prime importance.
Feed quality is an intricate question, but the properties of suitable bovine and porcine diets are relatively easy to define because the animals respond visibly to deficiencies and imbalances. For example, a considerable proportion of reproductive disorders in dairy cows is caused by nutritional imbalances. In organic farming it is both possible and necessary to influence the ratios of calcium to phosphorus, potassium to sodium, protein to energy and the amount of roughage in bovine diets by crop rotation and fertilization. Our information on the influence of these relationships is largely derived from intensive animal industry, because overfertilization of pasture to get maximum - but not optimum - yields creates very high levels of potassium, phosphorus, protein, and nitrate in fodder plants.
The relation between nutrition and health in animals goes beyond questions of pasture fertility. It is becoming increasingly obvious that trace elements, minerals, and vitamins act directly on the immune system of the animals. The creation and preservation of a stable herd immunity is one of the principal aims of animal husbandry in organic systems. This is related to another important aspect: Feeding animals in a way that is appropriate to the species contributes to longevity, with the result that a satisfactory life yield becomes possible. For example, a recent study reported that a single sow produced 239 weaned piglets during her 12 years of life. Sustainable agriculture must use different species of animals according to their nutritional demands - ruminants to transform fibre, low-value protein, and nonprotein nitrogen into milk and meat; pigs to utilize waste grain and potatoes, garbage, and leavings. Since the intestinal tract of the pig is comparable to the human gut, pigs do best on a diversified diet.
One of the most frequently found diseases in farrowing sows is mastitis and metritis, caused by coliform bacteria. What makes these microorganisms dangerous is the production of an endotoxin. The same factors which cause a loss of gut motility, such as monotonous diets, also enhance the absorption of endotoxin, which makes the animals seriously ill.
Last but not least, an ethical argument in favour of a reasonable use of farm animals should be mentioned. In eggs, milk, and poultry production, the conversion of the crude protein in the diet into animal body protein is 22-25 per cent, but in beef and mutton it can be as little as 4-5 per cent. Energy conversion rates are equally poor. Is it reasonable that with such low conversion efficiencies intensive animal production can continue in the future?
Knowledge of how to produce animal products in organic farming systems in an environment of minimum competition between man and animals for nutritional resources is still restricted. But some scientists have already started interesting experiments, including a long-term investigation on milk production without concentrates, as a result of which a total of 20 dairy cows yielded an average of 4 851 kg of milk during their second lactation.
Animal nutrition in high external input systems. We will now look at how and why the equilibrium between nutrition and several other factors is disturbed in intensive animal production. Disturbances are usually caused by a high concentration of animals on farms and in certain regions, the unfavourable and excessive fertilization of farm-grown fodder, and the enormous input of concentrates.
Farm animals are, at least to a certain extent, able to defend their metabolic homeostasis against an unfavourable composition of diet. But modern fertilization methods very often alter the ratio of important ingredients to an intolerable level. For example, in one dairy herd with an extremely high incidence of metritis and retained placenta, the animals were being fed a diet containing too narrow a calcium to phosphorus ratio (about 1:1). The potassium to sodium ratio should be near 10:1, but intensively fertilized pasture grass or maize silage may show values of 100:1 and even up to 1000:1 Nevertheless, high external input systems are leading to a tremendous overproduction of milk and meat in several European countries. The social and ecological costs of this overproduction are beyond imagination. Agricultural economists used to believe that it was too expensive to feed calves whole milk. The result was that the butter fat was removed, the skim milk dried, and the milk powder stored up, resulting in a huge "butter mountain". A new proposal for putting an end to this nonsense cycle suggests that the butter fat should be mixed with milk powder in order to reconstitute milk. This would then be fed to calves.
In the Netherlands the regional concentration of animal production creates nearly unsolvable difficulties. Soils are already overfertilized, or rather polluted with phosphorus, copper, and nitrogen. This has forced the Government to stop the extension of animal production in certain regions by law. Again the proposed solutions look odd. Some scientists are reinvestigating the mineral requirements of cows and pigs, since they suspect that the recommended allowances are too high.
All these examples show that most of the agricultural scientists, politicians, and practitioners have not yet understood one of the central messages of our times: human beings, in their quest for economic development, must come to terms with the reality of resource limitation and the carrying capacity of ecosystems.
Animal health in an organic farming system. A sustainable state of good health in a herd implies more than the simple absence of diseases. It represents the result of many very different influences and actions. In other words, merely attacking diseases will not greatly improve animal health. Metabolic problems in dairy cows, such as ketosis, displaced abomasum, and ulcerated rumen can be prevented by avoiding heavy grain rations and feeding enough roughage, which is not a problem in alternative agriculture. Resistance to infectious diseases is mainly based on the specific and unspecific mechanisms of the host defence system. In the past few years we have learned that many more factors influence the immune system than scientists knew about even 20 years ago.
An indeterminable number of papers on the effects of environmental chemicals on the immune system have been published during the past ten years. The interesting fact is that low-level exposure to pesticides and heavy metals, even though it does not cause visible symptoms of intoxication, may induce subtle alterations in the immune systems of many animal species.0
The feedstuffs used in organic farms should have a low level of such substances; this could help to build up animal health. Unfortunately, some kinds of environmental pollution, such as radioactivity and toxic heavy metals, have already spread out all over the world, so in this regard organic farming is as vulnerable as conventional agriculture.
An increasing number of people are now clearly stating that the basic ethological needs of farm animals must be met in husbandry. But only a few have realized the enormous commitment required to modify husbandry standards and methods in order to meet these needs.1 Thus it remains one of the future tasks of biological agriculture to develop appropriate housing systems and to introduce them into organic farming systems. For one thing, a proper environmental and ethological design for husbandry systems reduces the stress level in farm animals. This is important because stress hormones may impair the resistance of farm animals to infectious diseases. Another factor influencing animal health consists in the man-animal relationship. Thus it is no wonder that scientific investigations on such topics as the personality of the successful dairy stockman are appearing.2 In the most striking of these reports, an investigation of calf mortality on several farms, the author found that if the animals were cared for by the farmers wife, the average mortality was only 1 per cent. Mortality increased to 3 per cent if the farmer himself did the job, and reached 9 per cent if the animals were tended by hired staff.3
Animal health problems in high external input systems. Animals housed in modern confinement buildings suffer from several management-related stresses, including animal density, crowding, handling procedures, social status, psychological distress, and noise. Stress may not only affect the immune system but also the hormonal homeostasis of animals. This can be clearly shown with regard to the relationship between stress and fertility.4 Stress hormones may also be of major significance to bovine udder health. They probably promote conditions inside the udder which are favourable to the invasion, survival, spread, and proliferation of bacteria.5 Thus it is easily understandable that infertility and mastitis are two major health problems in modern dairy production.
With growing specialization and intensification, animal production has concentrated in certain regions. Thus a pig belt extending from northwestern Germany across the Netherlands and Belgium to the northern parts of France has come into existence. This concentration has brought about both environmental pollution and severe animal health problems. An enormous density of fast-growing or high-yielding animals represents optimum conditions for the attack of viruses and bacteria. For more than ten years these countries have been facing Aujeszky's disease, which affects pigs, cows, dogs, cats, and other species. Despite numerous legal regulations and good cooperation between agriculture and veterinary medicine, the number of outbreaks in the Federal Republic of Germany increased from 631 in the year 1980 to 1704 in 1985.6
In organic agriculture, the use of antibiotics to treat animal diseases is banned or restricted to exceptional situations. Difficulties arose because alternative veterinary medical methods to replace these remedies were underdeveloped, but now many veterinarians have learned to use homeopathy, acupuncture, and other therapies. These methods of treatment, based on a holistic approach, stimulate the regulatory facilities of the body to restore the disturbed order. In addition, homeopathy and acupuncture have the advantage that they leave no hazardous residues in milk, meat, and eggs.
The application of antibiotics is part of a very different concept. Its most important principle is to fight pathogenic bacteria, but such methods do not adhere to the rule of ecology. And in fact nature has already taken revenge. The problem of microbial resistance to most of the commonly used antibiotics is growing progressively worse. Unless drastic steps are taken, and taken in time, antimicrobial therapy as it has been practised for the past 40 years may no longer be effective by the end of this decade. If that comes about, the world will actually be worse off than before the advent of the antibiotics because today there is a new kind of farm animal: kept in narrow spaces in confinement buildings, stressed by labour-saving housing systems and having an immune system substantially compromised.7