Gordon King, Animal Science, University of Guelph
Domesticated animals served as an integral part of food production for thousands of years, providing draft power to plant, harvest and transport crops, in addition to yielding meat, eggs, dairy products, fertilizers, leather and other by-products. Only a portion of the potentially arable land in the world is really suitable for growing grain, vegetables or fruit, but substantially more provides grass or forages that can be harvested by or for livestock. In spite of Malthus and the recent contention that the feeding of grain to animals in the more advanced countries causes hunger in other regions, livestock will continue to have a place in future agriculture.
Food production from all animal and plant sources increased steadily during the past century and has at least kept pace with population growth. Some projections, however, show demand continuing to rise exponentially against a supply that may only be capable of linear increase, or might even become static. Although many subsequent economists ignored or discredited the Malthusian, assumptions, conclusions and predictions, the dramatic population increases occurring over the past few decades is reviving interest in his hypothesis.
As illustrated in the preceding figure, all of the major food types, including milk and meat, increased substantially over the past three decades. Barring severe alterations in climatic patterns or serious political unrest, the trend should continue. Technical innovations, combined with even greater emphasis on recycling and conservation, should insure a steady increase in food productivity. Whether or not people starve in the future depends not on farmers' ability to produce food, but on more effective programs for redistribution of wealth, control of population growth and on governments' willingness to implement these.
Population growth in total numbers and affluence during the past half century increasd the demand for meat, poultry and dairy products in both local and global markets. These greater marketing opportunities transformed much of the world's livestock farming from a casual and usually extensive operation, relying mainly on crop residues and by-products, into one that actively seeks inputs in competition with other food sectors. A more intensive agriculture creates additional pressures on finite land and other resources, often with detrimental effects on the environment. Hopefully, a holistic assessment of the entire farming enterprises will provide solutions that restore natural checks and balances.
Our existing croplands, rangelands and forests all utilize photosynthesis for biological activity that supplies almost all food and many of the raw materials used by humans. Modern livestock production, like all intensive agriculture or other uses of the biosphere's resources, is concerned with the flow of materials and money through the system. Its success or failure has been measured only in productivity and profitability. In the future, environmental and social components should be included in such calculations.
The amount of cultivated land increased steadily from the beginning of agriculture until very recently and this was certainly a major factor in expanding agricultural outputs. However, since 1981, land disappearing through degradation or urbanization offset any new areas brought under cultivation. The Food and Agriculture Organization of the United Nations (FAO) estimates that, of the 13 billion hectares of land possessing reasonable potential for biological activity, 11% is cropland, 25% is pasture and 31% is forest or savanna. The remaining 33% is either wasteland, desert or paved, with little productivity remaining. Immediate conservation and effective use of all available land is essential to insure adequate nutrition for future generations.
As population increases, lands that are less suited to cropping but are being grazed by domesticated animals, must be cultivated. Thus, direct competition between humans and animals intensifies with livestock then relegated to the most marginal regions. The resulting over-cropping and grazing, combined with increased need for firewood, causes even greater pressure. This may lead to reduced biological productivity and eventually even total degradation. When such deterioration occurs on arid or semi-arid lands it is called desertification since desert-like conditions appear where they had not existed previously. Domesticated animals contribute to desertification and must be restricted in any control or regeneration programs, but they are the agents of destruction rather than the underlying cause. It is only after humans elect to increase herd or flock size to the point where these exceed the land's carrying capacity that problems occur.
Although grasslands are still extensive, severe stress through overgrazing occurs in many regions. The problem is most severe in Africa where the human population increased from 223 x 106 in 1950 to 728 x 106 in 1995. Throughout the same period total livestock numbers actually went down from 642 x 106 in 1950 to 479 x 106in 1995 (World Resources, 1996-97 and FAOSTAT Database, 1997). Unfortunately, the combined human and animal populations grossly exceed carrying capacity in most semi-arid regions of this continent and desertification is spreading. Some argue that livestock should be eliminated but they provide service to the rural African economy, contributing several diverse socioeconomic functions beyond simply supplying consumable products, convertible products and draft power. Some control of populations, both animal and human, combined with eco-friendly husbandry would be a better solution. As in any other region, domesticated animals can be detrimental or beneficial to the environment. The precise effect depends entirely on how many they are and how they are managed.
Loss of habitat for both flora and fauna is another important consideration. Wildlife, however, have a much better chance of surviving with grazing land than they would with cropped land. Perhaps there is some validity in Dennis Avery's argument for applying even greater technology to increase the yield from land that is currently under cultivation so that the remaining natural habitat can stay undisturbed.
The following table illustrates that the situation in our own rural region is certainly not static. Research and extension activities supported by government and producer groups substantially increased productivity per unit of land so less was needed to produce more. Continued progress should ensure that Ontario livestock farmers remain competitive in regional and global markets. This reduction in farms numbers and associated labor opportunities certainly affects the rural economy and social structure. Now in Ontario, as in many other industrialized countries, we have an overabundance of many commodities. While certainly not as devastating as shortages, this excess also creates socioeconomic problems which are particularly serious in rural areas.
|
1951 |
1991 |
Farms |
93,564 |
8,940 |
Land, ha |
727,000 |
371,000 |
Pigs marketed |
2,700,000 |
3,900,000 |
Lean pork, tons |
87,000 |
159,00 |
Agri-food Research in Ontario, Sept. 1993.
Although Canada does not yet face serious problems from either animal induced desertification or pollution, the potential exists. As units get larger, concentrating more and more animals into smaller areas, the possible disaster that might arise from environmental defilement increases. Thus, farmers must be aware of the hazards and take appropriate precautions in managing manure and agrochemicals to prevent any water or soil contamination.
Accumulation of carbon dioxide and certain other gasses in the atmosphere may be contributing to a global warming trend or "greenhouse effect". Carbon dioxide, generated by fossil fuel based industrial processes, is the major contributor accounting for approximately half of the increase. Methane, which originates from a number of sources, including several agricultural activities, as shown in the following Table, contributes perhaps 20% to total warming. Since ruminant animals produce methane as a by-product of their digestive fermentation, they contribute to a "greenhouse effect".
|
Approximate % |
Natural wetlands
|
21 |
Wildlife/termites
|
7 |
Oceans
|
3 |
Biomass burning
|
10 |
Rice paddies
|
20 |
Livestock
|
14 |
Fossil fuels
|
14 |
Landfills
|
7 |
(Feedstuffs, 91/02/18)
Although livestock contribute to global warming through generation of methane, their elimination would not abolish the treat. Many ruminants are needed for draft purposes in developing countries. If fossil-fuel-burning machines replaced these working animals, some reduction in methane might result, but this would be offset by higher carbon dioxide production. Appropriate husbandry minimizes methane production and use of such knowledge should be expanded. Unfortunately, although relatively simple and inexpensive procedures to improve the digestibility of poor quality roughage and residues exist, these are not yet used widely beyond research institutions. Several examples are the urea-molasses blocks or urea treatment of straw.
As shown in the following table, just inclusion of a few nutrient supplements will substantially increase the efficiency of rumen function with a significant reduction in the amount of methane liberated. Since approximately two-thirds of the world's ruminant population is located in Asia and Africa where crop residues and by-products are the common diet, anything that improves digestibility would also decrease methane.
Methane Output and its Ratio to Meat Production in Growing Cattle Fed Straw Alone or With Supplement. |
||
|
Straw alone - No supplement |
Urea, mineral & bypass protein supplement |
Digestible energy fermented to methane |
15% |
8%* |
Ratio, methane to meat |
2.4 |
0.36* |
*Statistically significant
difference. |
A major limitation on many agricultural systems is the inability to develop or maintain an optimum degree of enterprise diversification. Suitably designed mixed farming, with a balanced integration of crops and livestock, exploits complementary relationships. A possible alternative where specialization is already well established might be for neighboring crop and livestock farmers to form cooperative ventures. Initially, this might be using animal manure to replace some of the chemical fertilizer purchased for and applied to the croplands, combined with feeding surplus grain to the animals. Eventually, the collaboration could evolve to the stage where forages were rotated with the cereals. Synergism between plants and animals should benefit the entire ecosystem regardless of geographic location or socioeconomic structure.
Detractors frequently point out how much fossil fuel energy is required for intensive livestock production. The following figure, illustrating the allocation of energy usage in the more developed countries, shows that all forms of primary agriculture use only a very small proportion of total consumption.
What the previous figure does not reveal is that a substantial proportion of industry and transport energy would be devoted to moving, processing and merchandising food, as well as considerable residential-commercial energy expended in food preparation and storage. Thus, the modern, industrialized agri-food system will consume considerable energy, regardless of whether the processed product is of animal or plant origin.
Professor Colin Spedding, University of Reading, examined energy ratios and inputs throughout the human food chain and makes some interesting comparisons. He points out that wheat is more efficiently produced than milk, if the calculation only extends to when the commodity leaves the farm. However, milk can be drunk virtually as it is, incurring rather small additional energy costs for transport and processing. In contrast, wheat must be ground and cooked, involving processes which require substantial energy costs, in addition to those associated with packaging, transport and storage. Thus, for the product that is finally consumed, there is very little difference in the final inut:output ratios for bread or milk.
Efficiency of Energy Use in the Food Chain
|
MJ of energy in product per MJ support energy used |
Wheat at farm gate |
3.2 |
White bread - sliced and wrapped |
0.5 |
Milk at farm gate |
0.65 |
Milk - bottled and delivered |
0.595 |
Spedding, 1988
Critics attack livestock production and meat consumption as inefficient use of resources, inferring that the cereal grain consuming livestock industry in Europe and America is a major cause of malnutrition in other regions. As shown in the previous figure and table, primary agriculture accounts for only a very small proportion of the total energy consumption in industrialized countries. Far greater amounts are used in food processing and preparation. The energy expenditure after commodities leave farms is unlikely to change regardless of whether the basic food ingredients are animal or vegetable.
The degree of productivity realized from domesticated animals depends on genetics, which dictate the inherent potential to produce, and the environment which governs how much of the potential can be realized. Genotypes by environmental interactions are often considered but this is perhaps an oversimplification of the actual situation in livestock production systems. Neither animals nor animal attendants are created equal and the latter can manipulate both the animal's genotype and its environment. Some attendants, through instinct, experience, training or a combination of these, are more capable of satisfying the basic requirements needed for their animals to perform properly. Others, with little regard for animal welfare or appreciation of fundamental needs, fail to provide even the minimum requirements necessary for comfort, health or productivity. Thus, livestock production involves a complex interaction between genotype, environment and management.
The two extremes for improving the productivity of livestock are:
Finding animals that can adapt and be somewhat
productive
over a wide range of environments and selecting from them.
OR
Finding animals that are most productive under controlled
environments and selecting from them.
The latter system is most usually adopted in the industrialized countries and, while it may be suited to their situation, is not always the proper approach. The following table, showing performance of several genotypes under normal or potentially distressing conditions, illustrates a genotype by environmental interaction. In temperate climates or under environmentally controlled conditions where animals are rarely exposed to temperatures above their comfort zones, the Herefords performed better than the Zebus. In contrast, when the degree of heat stress was high, as would be common for many tropical regions, daily gain was better in Zebus.
Heat Stress |
Zebu |
Crossbred |
Hereford |
Low
|
0.75 |
0.81 |
0.84 |
Medium
|
0.29 |
0.37 |
0.27 |
High
|
0.25 |
0.21 |
0.11 |
Frisch & Vercoe, 1977, Anim. Prod. 25:343
Animal production systems should be matched with or modified to suit particular environments. There is nothing morally wrong with intensively managed dairies, poultry units, piggeries or feedlots in locations with abundant feeding grade cereals so long as these are viable economically and improve rather than degrade the environment. At the present time, many north American farmers would have no market for their grain unless it is processed through livestock somewhere in the world. However, the appropriateness of such operations in regions where food might be limited should certainly be questioned. Regardless of the location, animal production systems should optimize the use of local resources.
Numerous programs intending to improve animal production in developing countries through introduction of temperate genotypes and production systems have benefited the providers of animals and technology in the donor country much more than the farmers in the recipient country. Most of these aid projects survive through the initial phases when donor support remains high but disappear soon after the withdrawal of foreign inputs and financing. Politicians, bureaucrats and even some research scientists seem to place great faith in technology. Technical innovations may allow reasonably competent managers to do an even better job but they are not panaceas that will convert poor managers into successful ones. Nor will they allow "exotic" genotypes to remain productive in regions that are resource poor. Similarly, mechanization may allow laborers to do more work but not usually better work. A stated previously, livestock production involves a complex interaction between genotype, environment and management, with genotype dictating the potential to produce, the environment governing how much of this potential can be realized and management influencing both of these components. Relatively inexpensive energy, combined with generous direct and indirect subsidies, allow farmers in the developed regions to modify environments with conditions fluctuating only through narrow ranges so that their animals should perform well. Such luxury is not available to farmers in the lesser developed parts of the world and may not persist even in the industrialized countries. A better long term strategy for the continued production of livestock products in much of the world might be to select for animals that can adapt and be reasonably productive through a wide range of environmental conditions. Some of the breeds found in the tropics already possess this ability.
Regardless of the location or environment, universal necessities for improving livestock performance are: the selection of capable and motivated people, obtaining appropriate genotypes' and providing all essential inputs. These must be combined in a satisfactory environment for the animals and working conditions for the attendants to allow effective function. In addition, there are many other environmental and even socioeconomic challenges to be overcome before satisfactory production is achieved. Regardless of the situation or location, the people involved with the daily care of the animals are the key component and should always be considered before initiating any changes. The largest renewable resource throughout the lesser-developed tropics is human labor. Mechanization and many intensive production practices fail to take advantage of this. The challenge for donor agencies or anyone else involved with improvement of livestock production or any other form of agricultural development, is to modify any technology that is transposed from industrialized countries to tropical areas so that it makes maximum use of all the locally available resources.
Phase One: (17th through 20th centuries) Farming techniques, transferred directly from the home regions located in temperate climates to new territories, usually worked with little or no modification throughout much of the "new world." Several notable exceptions were that farmers moving into much of Australia, parts of southern Africa and the midwestern plains of north America attempted to adapt practices devised in small, wet fields of Europe to the vast and often semi-arid planes in other locations. This produced the dust bowl disaster experienced in midwestern USA and Canada during the 1930's and the environmental degradation still occurring in some regions of the world.
Phase Two: (mid to late 20th century) The age of technology in which most people believed the future was assured through application of "techno-science." The general feeling was that continued scientific research and development could solve all future problems. Then Rachel Carson wrote a book called Silent Spring. Some of her initial warnings about effects of DDT may have been exaggerated but the underlying message concerning dangers of contamination in the food chain and soil erosion were not.
Phase Three: Today, the only certainty is that we are in an age of uncertainty. Localized food shortages still occur but surpluses now exist throughout much of the world. Even in the more affluent countries, the economies are no longer expanding rapidly so many subsidy programs must be curtailed or redirected. The future in the more developed countries will likely include more community concern and hence government intervention in environmental aspects, animal welfare issues, food safety and resource depletion.
Even conservative estimates indicate that world population will exceed 6 x 109 by the year 2,000, with 5 x 109 in the developing countries. However, The Food and Agriculture Organization of the United Nations (FAO), with full appreciation of the current exponential population growth, predicts food supply will be sufficient to actually reduce the proportion of undernourished humans during the current decade. Food For All, published by FAO on the occasion of the World Food Summit held in November, 1996, contains a number of interesting sections covering how the world's population can be fed now and in the future. The second chapter, "How many people, how much food?" stated: "Projections much beyond 2010 are difficult to make. Although as they get richer, people in the developing countries eat proportionally more meat and less grain, not all of them will choose to eat such large quantities of meat as people in the western industrialized world. Estimates of agricultural production in the post-2010 world suggest the following:
FAO predicts increased pig and poultry production that will create a corresponding increase in demand for monogastric feed. An inability to grow excess cereals, combined with the lack of foreign exchange to purchase these for inclusion in livestock rations, should encourage greater utilization of non-conventional feed sources in tropical and subtropical countries. Sugar cane juice and crop residues can supply the energy requirements for mature monogastric and ruminant animals respectively, but must be supplemented with protein and minerals even for maintenance. Research in the field of animal nutrition has identified a number of practical energy-protein-mineral supplements that could be available throughout the developing world. Also, ensiling or chemical treatments improve digestibility of crop residues and agri-industrial by-products. Using this available and relatively simple technology in extensively integrated systems, as illustrated in the accompanying picture, can be justified on a socioeconomic basis in many tropical and even temperate climates. This holistic approach should be incorporated into effective government support and extension programs. If this occurs in sub-humid tropical regions and fair, free trade becomes a reality, developing countries might then provide more animal protein for humans in the already industrialized countries.
Sustainability seems to be the popular buzzword of our present era. A reduction in use of nonrenewable inputs and recycling of resources to the maximum extent that is possible are certainly worthy aspirations. It must be appreciated, however, that if the world's population is to be fed adequately, agriculture cannot abandon all technological inputs and revert totally back to the traditional farming methods of previous centuries. Rather, sustainable agriculture must evolve into practices that preserve or improve the quality of soil, water and air, while still permitting competitive production of wholesome food in adequate quantities under a socioeconomic structure that is fulfilling to all people involved. In most instances this will involve mixed farming systems designed to use all inputs to optimum advantage while preserving the environment. Traditional practices should be re-evaluated to determine which might still be applicable or should be revived. This requires critical evaluation combined with some imagination to select those components or practices that will contribute to future sustainability. Probably any such exercise performed in north America during the nineteenth century or first half of this century would have concluded that the draft horse must be preserved. Today, if our farmers relied totally on equine draft power, a substantial proportion of cropland would be growing horse forage rather than human food. While this might reduce domestic surpluses of cereal grains, it would also curtail the amount available for export to countries with food shortages. The challenge is to develop appropriate animal and crop production systems that conserve finite resources and optimize input:output ratios. These must be combined with land management and manure handling systems that are ecologically friendly. It is doubtful if we have yet developed the appropriate knowledge or tools to accomplish this in the temperate regions.
Many years ago an outstanding naturalist had this to say about the
effort to preserve wild flora, fauna and habitat in America.
"We tilt at windmills in behalf of conservation in convention halls
and editorial offices, but on the back forty we disclaim even owning a
lance"
(Leopold, A. 1949, A Sand County Almanac, Oxford).
Sadly, any concentrated effort to promote either conservation or an
ecologically friendly, resource-conserving agriculture in the
industrialized countries is at the same stage today.
With good animals and all the necessary inputs available for proper housing, feeding and disease prevention, a competent manager should be able to develop a system that allows livestock to produce efficiently, expressing much of their inherent genetic potential. Whether this is profitable depends on the total cost of all inputs and how these relate to the value of product generated. The science of animal production has advanced to the state where knowledge exists on how to maximize many of the components involved with livestock performance. Unfortunately, for some of these procedures the cost associated with providing the required inputs may exceed the market value of the additional commodity produced. In addition, current market forces and government policies pay insufficient attention to intangible or non-economic considerations such as resource depletion, environmental quality, social considerations or animal welfare concerns. Hopefully, all of our future livestock production will improve rather than degrade environments, use local resources effectively, minimize reliance on energy intensive inputs and reduce stress for both the animals and humans involved.
Remember that sustainability, although practiced in some form or another by subsistence farmers for many millennia, is a new concept for intensive food producers. All of the people involved with the operation of intensive livestock units must seek continuously for procedures that, while still allowing economical operation, conserve resources, prevent environmental degradation and improve social conditions.
Visit The Ecological Farm for additional ideas and examples of what can be accomplished.
The operation of a mixed farm demands considerably more knowledge and skill than is necessary for a monoproduct unit. Perhaps a substantial proportion of the people farming currently in the more developed regions will require training before they can face this challenge.
Although production systems may change dramatically, agriculture will remain viable since the amount of solar radiation used or wasted today does not affect the amount available tomorrow. Thus, the major energy source is sustainable and conventional agriculture will continue as the most important source of human food. On good land, plants will produce more energy and protein per unit area than animals but, when output is expressed in monetary terms, animals often generate higher returns. Major Challenges include controlling production costs, satisfying animal welfare concerns, arranging fair international trade and insuring that production is eco-friendly.
If animal production is to continue contributing towards environmental improvement, farmers must be motivated to initiate and persist in ecologically friendly practices. Wherever industrialized practices prevail, this requires a new method for assessing yield from a farming operation. Currently, most systems would use the formula:
This is certainly an incomplete calculation for intensive farms. The entire region, both rural and urban, subsidizes many of their inputs and suffers from any undesirable social effects or environmental degradation resulting from the operation. Whenever high input agriculture is practiced, the individual farm boundary extends far beyond even the geographical region. A better formula that should be adopted for future evaluations is:
This would include some form of credit or subsidy for operations that contributed in some way to ecological improvement or a penalty tax on those with any detrimental effects. Many of our current farms might be assessed neutral and receive no credit or penalty. The goal should be to modify all of these to a credit status. One problem would be agreeing who or what body should determine status and evaluate impact. A logical candidate would be government but this is perhaps not the best agency. Modern farming has moved from a life-style to a profession and it is time that farm operators began viewing themselves as professionals. This could lead to the formation of a professional organization with responsibility for regulating members. Such a group would be in a better position than government bureaucrats to pass judgment on other farmers for both environmental and animal welfare concerns.
Requirements for a more resource conserving agriculture under intensive farming conditions involves professional managers who:
The National Hog Farmer magazine, the National Pork Producers Council and Pfizer Animal Health Products sponsor an environmental recognition program that rewards individual producers for innovative actions relating to manure, wildlife or financial management, aesthetics and neighbor relations, or other innovations that make pig production more eco-friendly. Too see what is happening, visit this site to check out the criteria for nomination-selection and to meet some of the recent winners.
Additional information relating to sustainable agriculture can be found at the following sites:
The Sustainable Agriculture Network (SAN)
Sustainable Agriculture Research and Education Program
Manaaki Whenua Landcare Research
The Rural Advancement Foundation International (RAFI)
Much of the present conflict between livestock and environment is perhaps described with considerable accuracy in the following quotation:
"--- that once plants and animals were raised together on the
same farms - which therefore neither produced unmanageable surpluses of
manure, to be wasted and to pollute the water supply, nor depended on
such quantities of commercial fertilizer. The genius of American farm
experts is very well demonstrated here: they can take a solution and
divide it neatly into two problems."
W. Berry. The Unsettling of America: Culture and Agriculture. Avon. New
York. 1977.