Modalities of integration
Components of the integrated system
Constraints of integrated systems
Examples of integration
Conclusions
Bibliography
M. SánchezThe author is Animal Production Officer (Animal Nutrition), Animal Production and Health Division, FAO, Rome, Italy.
Several kinds of integrated agriculture systems, for example, livestock associated with fish ponds and fish with rice (Mukherjee, 1992), sugar cane with livestock (Preston and Murgueitio, 1992) and multipurpose trees with crops (Speedy and Puglièse, 1992), are of current interest in developing countries concerned about the efficiency and conservation of the environment. The integration of livestock with perennial crops may also increase productivity per unit of land in a sustainable manner.
Livestock have been associated with perennial crops in one way or another for a long time. Various domestic animals roaming around the backyard underneath fruit-trees is a common scene in tropical regions. It has also been a traditional practice in many areas of the world to use animals, especially sheep, to control weeds in plantations. People benefit from the proximity of plantations where they can graze their animals, if permitted, or collect forage for their livestock kept in confinement.
There are several advantages of integrating animals with perennial crops, apart from the direct benefits of their products (meat, milk, fleece, skins and manure). Grazing animals reduce or eliminate the need for weed control. Undesirable plants, or weeds, become forage, and thus the basis for animal production. Biological weed control using animals offers a much better and cheaper alternative to using herbicides, which could represent a potential hazard to the human and animal environment. Most of the studies and observations made on animals grazing perennial crops have shown increased yields of the main crop - trees. This is probably because of the combined effects of weed control and improved recycling or availability of soil nutrients. Animal production may be the only source of income during the first few years of tree growth, before they become productive. The presence of livestock in plantations keeps the understorey vegetation shorter, which in the case of rubber tree plantations facilitates the daily passage by tappers and in coconut plantations it makes the locating and gathering of nuts much easier.
The system of integrating livestock with perennial crops must be comprehensive, taking all system components into consideration. In most cases, the perennial crop is the main element of, if not the reason for, the system, and it should therefore receive priority. Other physical (soil, nutrients, water, light) and biological (understorey vegetation, animals) components also need to be taken into account, however, and certain compromises in the main crop's potential yield may have to be made in order to have greater total productivity and income and a more sustain-able and environmental] y friendly system.
The integration of livestock with perennial crops can be practised in many different ways in relation to time, space and climatic conditions, independent from the specific species of plants and animals involved. One of the simplest approaches is to use neighbours' animals to graze the natural annual vegetation growing during certain times of the year, particularly after the rainy season, for example, sheep grazing in olive-growing regions (Vera y Vega, 1986) or the seasonal feeding of prunings, such as orange prunings for sheep (Borroto et al., 1989) and olive prunings for cattle. In semi-arid regions, seasonal multi-animal grazing is practised in plantations of Agave and Opuntia species.
A more continuous integration is the year-round grazing of local animals on native vegetation growing in tropical tree plantations, for example, ruminants under coconut trees (Reynolds, 1988). A variation of this system is the cut-and-carry of native grasses for livestock kept in confinement, for example, forage from coffee plantations in eastern Java (Iñiguez, 1990, personal communication) and from orange plantations in Cuba for sheep (Borroto et al., 1985) and from rubber plantations in northern Sumatra for cattle.
In a more sophisticated system, both the understorey vegetation and the animal species are specifically selected for the integrated system, taking into consideration the existing characteristics of the perennial crop, the soil and the climate. This is the approach that has been taken to search for forage varieties that can be planted under rubber trees for grazing sheep and under oil-palms for both sheep and cattle (Shelton and Stür, 1991).
A further refinement is to plant the perennial crop using spacing and patterns that would be most beneficial for the whole integrated system, paying particular attention to the light requirements of the cover crop, such as oil-palms, planted with animal integration in mind.
Physical components
Soil and minerals. The physical and chemical characteristics of the soil partly determine the kind of forage species that grow naturally or that can be introduced. Limited modifications in the soil structure can be envisaged in order to promote the growth of the natural vegetation or that of the cover crop. For example, the addition of lime or phosphorus fertilizers would promote legume growth (Skerman, Cameron and Riveros, 1991). Depending on existing conditions, there could be competition for water and minerals between the main crop and the understorey vegetation. The presence of the latter will, of course, increase the organic matter of the soil and thus improve its water-holding capacity and fertility. Ruminants speed up the recycling of nutrients back into the soil via urine and faeces following the microbial digestion and the metabolism within the body.
In certain circumstances, some soil structures might not tolerate the presence of grazing animals because of excessive soil moisture or the potential problem of soil compaction. The latter would also need to be taken into consideration in the case of mechanical harvesting or cut-and-carry systems.
Water. Water availability is one of the main factors determining the seasonality of forage growth. In the humid tropics, there could be adequate moisture for forage growth during most of the year, but the lack of forage during the dry season would be the main factor limiting the integration of animal production into plantations.
Light. Most perennial crops, especially rubber trees, begin to absorb sunlight at a very early stage and can reach very high levels of absorption of the photosynthetic active radiation (>95 percent) after several years (Sánchez and Ibrahim, 1991). Consequently, light could become the single most limiting factor for forage growth (Chen, Wong and Dahlan, 1991).
The typical cycle of plant composition under rubber trees or oil-palm begins with a mixture of grasses, legumes and other forbs, depending on whether the vegetation is natural or artificially planted. After a few years the broadleaves and legumes disappear and only some grasses will remain (Wong, 1991). Eventually all understorey plants will cease to grow until the canopy stretches vertically and some light gets through by reflection. The species that start to grow at this stage depend not only on the light conditions but also on the availability of seeds for self-regeneration.
The pattern in which trees are planted can make a difference in terms of light interception. In tropical areas, trees aligned east-west would allow maximal light penetration to the understorey vegetation.
Biological components
Perennial crop. Above all other factors, the nature of the main crop and its cultural practices determine whether any integration is possible at all, or its modality. Favourable plants for livestock integration would be those least prone to damage by animals because of their height, palatability or toughness of stems and leaves. Adult trees such as palms (oil and coconut) and rubber trees, thorny xerophytes such as Agave and Opuntia, or unpalatable plants, for example, Aloe vera, are good possibilities. Fruit-trees could also be used for integrated systems once they have reached a certain height. Among tropical fruit-trees, mango, avocado, rambutan and durian trees would be suitable, as would pear, peach, apple, orange and olive trees among the temperate fruit-trees.
Given the fact that in many countries large areas are planted with orange trees, the integration of animals with this fruit crop could offer interesting possibilities. Work has been ongoing in Cuba to develop a system of integrating Peliguey sheep into orange plantations (Borroto et al., 1986). The main problem encountered here has been how to keep damage to the low branches to a minimum by means of grazing systems and restraining devices. In modern, intensively operated orange plantations where trees are pruned low for easier picking and where fruit-bearing branches reach the ground for maximized yields, grazing would not be desirable. In older plantations with higher canopies, however, the presence of animals may not cause any more damage than that caused by agricultural pruning and weed control equipment.
Understorey vegetation. In the simplest forms of integration, natural vegetation in plantations is used for grazing or cut-and-carry. Some of the unpalatable vegetation, such as Eupatorium odoratum, Melastoma malabathricum and Imperata cilindrica, and toxic species, such as Lantana camara and Asclepias curassavica, will remain as weeds, while most of the rest will be used as forage once the animals enter the system. Species growing spontaneously at any particular place might be a mixture of grasses, legumes and broad-leaved plants. Some of these would be consumed more than others, depending on the animal species involved (Tajuddin and Chong, 1991); for instance, sheep prefer tropical legumes and broadleaves over grasses.
When the understorey vegetation is artificially planted, it is referred to as cover crop. If properly selected, it offers many advantages for the main crop and the system as a whole. Cover crops can effectively protect the soil from hydric and aeolic/rain and wind erosion, increase the soil's organic matter, fix nitrogen (legumes), reduce soil moisture loss and topsoil temperature, reduce or eliminate weed growth and provide excellent forage for grazing or cut-and-carry systems.
The ideal cover crop should have the following attributes: easy establishment either vegetatively or, preferably, from seed; excellent soil cover without climbing up the main crop; minimum competition for water and nutrients; adequate nitrogen-fixing capacity; good growth under a variety of light penetration levels characteristic of the main crop; persistence under grazing or cut-and-carry systems; high palatability and nutritive value for the intended animal species; and low potential of becoming a weed beyond the integrated system.
In tropical climates, legumes are preferred over grasses for integrated systems with small ruminants since they are generally more nutritious and contribute to higher levels of animal production. Some tropical legumes are not palatable to animals, such as Calopogonium caerulium. The standard mixture of legumes currently used as cover crops for rubber and oil-palm plantations in Southeast Asia includes Centrosema pubescens, Pueraria phaseoloides, Calopogonium muconoides and Calopogonium caerulium. Of these, only C. pubescens is palatable. P. phaseoloides is only partially consumed and the Calopogonium species almost not at all. The latter species are the most shade-tolerant, however, and thus last longer underneath trees.
Animals. The animal species that have been used with perennial crops range from cattle under coconuts (South Pacific) and oil-palms (Malaysia and Cameroon) to geese under orange trees (Cuba) and ducks under plantains (Dominican Republic). Sheep, because of their docile nature and tendency to graze rather than browse, have been preferred in association with rubber (Malaysia, Indonesia), orange (Cuba), peach (Mexico), olive (Spain) and other fruit-trees. They also integrate well in Aloe vera plantations in the Dominican Republic. They do not consume the aloe leaves except for a few days right after harvest when the aloin-free tissue is temporarily exposed. Dwarf goats from Southeast Asia have been integrated in rubber plantations in Indonesia. Their small size prevents them from causing any major damage to tree foliage, provided that there is plenty of forage for them to select. A study recently completed in Cuba (F. Ojeda, personal communication) has shown the potential of grazing horses in orange plantations. Horses are able to eat very low-quality grasses and do not touch the foliage from orange trees.
Under cut-and-carry systems, all ruminant and herbivore animal species that can be kept in confinement may be integrated with perennial crops. It is only under direct grazing systems that the animals need to be well selected. For example, poultry (chickens, turkeys, guinea fowl), small deer and small African antelopes would be suitable for integration with perennial crops.
The management of livestock under perennial crops has varied from practically non-existent, where the animals are released during the day to roam freely on the plantations, to grazing with a shepherd, to rotational grazing with electric fences. Much better use of the forage resources is achieved with controlled grazing, both in terms of space and time. There is also less risk of tree damage since the animals are brought to the plantation only to graze and can be supervised. Ideally, they should spend their periods of rumination and rest in the corrals.
Since it is unlikely that nutrient requirements for optimum performance of the animals can be met throughout the year only with forage, some sort of feed supplementation may be justified during certain periods of the year (Sánchez and Pond, 1991). Energy, sodium and other minerals are the nutrients most likely to be lacking in integrated systems under trees. Although supplementation of sheep grazing in rubber tree plantations with protected protein in the form of fish-meal did not show any positive effect (Sánchez and Pond, 1990), a variety of forms of energy supplementation consistently improved sheep performance (Sánchez and Pond, 1991).
Examples of livestock integration with perennial crops - Exemples d'intégration élevage-cultures pluriannuelles - Ejemplos de integración de ganado con cultivos perennes
|
Type of system |
Crop |
Animals |
Mode |
Country |
References |
|
Grazing |
Rubber |
Goats, sheep |
Continuous |
Malaysia, Indonesia |
Iñiguez & Sánchez (1991) Arope, Tajudin & Chong (1985) Devendra (1990, personal communication) |
|
Oil-palm |
Cows, sheep |
Continuous |
Malaysia |
Chen (1991a, 1991b) | |
|
Coconut |
Cows, goats, sheep |
Continuous |
South Pacific |
Dalla Rosa (1993) Reynolds (1988) | |
|
Aloe |
Sheep |
Continuous |
Dominican Republic |
Sánchez (1994, personal communication) | |
|
Sisal |
Cows |
Continuous |
Kenya |
Sánchez (1994, personal communication) | |
|
Acacia |
Ducks, sheep |
Continuous |
Dominican Republic |
Sánchez (1994, personal communication) | |
|
Orange |
Geese, sheep |
Continuous |
Cuba |
Borroto et al. (1985) Leyva, Lima & Alvarez (1990) | |
|
Musaceae |
Ducks |
Continuous |
Dominican Republic |
Sánchez (1994, personal communication) | |
|
Almond |
Sheep |
Seasonal |
Spain |
Vera y Vega (1986) | |
|
Pear |
Sheep |
Seasonal |
Spain |
Vera y Vega (1986) | |
|
Olive |
Sheep |
Seasonal |
Spain |
Vera y Vega (1986) | |
|
Peach |
Sheep |
Seasonal |
Mexico |
Sánchez (1994, personal communication) | |
|
Opuntia |
Goats, sheep |
Continuous |
Mexico |
Sánchez (1994, personal communication) | |
|
Agave |
Goats, sheep |
Continuous |
Mexico |
Sánchez (1994, personal communication) | |
|
Cut-and-carry |
Coffee |
Sheep |
Continuous |
Indonesia |
Iñiguez (1990, personal communication) |
|
Rubber |
Cows, goats, sheep |
Continuous |
Indonesia |
Sánchez (1994, personal communication) | |
|
Orange |
Cows, goats, sheep |
Continuous |
Cuba |
García et al. (1989) |
Annual forage shortages resulting from seasonal dry periods can be prevented by preserving forage using traditional methods (hay and silage) during periods of abundance or by using forage trees or sugar cane that can be harvested during the dry season. Tree prunings can also be fed to animals, but this can only be done during certain periods of the year so as not to interfere with the maximum benefit to the main crop.
Manure and urine from the animals return mineral nutrients and organic matter to the soil. Since it is most likely that in all integrated systems the animals will spend a considerable amount of time inside barns, it is important that the excreta is returned to the plantation as this will contribute to the sustainability of the system and will reduce or eliminate the need for chemical fertilizers. The additional minerals provided in the supplementation partially enter the nutrient cycle of the integrated system via animal excretions. A system that has worked very well over a long period of time has been that of introducing sheep into coffee plantations in East Java (Iñiguez, 1990, personal communication). The sheep owners are allowed to collect the forage under the coffee trees on the condition that they give a certain amount of sheep manure to each tree. Both the plantation managers and the sheep owners benefit from this arrangement while the system becomes environmentally friendly and sustainable.
There are several limiting factors in integrating livestock with perennial crops. One of the most important considerations is the possible damage to young trees or to the bark of adult trees. The size of the trees should determine when grazing animals enter the system. In the cut-and-carry system, however, tree size is not as critical. Proper animal management can substantially reduce or eliminate damage to bark by controlling grazing times and areas, by providing supplementary feeding, including minerals, and by removing horns and antlers from the animals. The confinement of males during mating seasons would not only encourage controlled mating, it would also prevent damage to trees.
A determining factor for forage production under trees is light penetration. In modern rubber plantations with improved clones and agricultural techniques, trees grow very fast and light penetration is reduced considerably in a few years, preventing the growth of most species. The long life span of tropical plantations permits various degrees of animal integration during the different stages of the tree production cycle. Young and old plantations allow more light penetration and thus favour forage growth.
There have been some reports of increases in rodent populations where there are legume cover crops. On one occasion, mice caused considerable damage to orange tree crowns when their numbers grew as a result of the more favourable habitat under a cover crop of Pueraria phaseoloides (Brache, 1992, personal communication).
Many large plantations in Southeast Asia still prohibit any sort of animal integration, including cut-and-carry systems, not so much because of the impact of the animals, but more to prevent the presence of people who pilfer plantation products and cause damage to trees when gathering fuelwood.
Existing integrated systems under grazing and cut-and-carry are indicated in the Table. The list is by no means comprehensive, but it includes examples of systems found in various countries around the world. The Table also provides information on plant and animal species and on whether the integration is continuous or seasonal.
With the ever-increasing demand for agricultural land to produce food for the human population, animal production systems will be increasingly dependent on alternative agricultural systems. Integrating livestock with perennial crops offers a unique opportunity to produce valuable animal products on land that is currently used for other purposes, making the overall system more sustainable and environmentally sound. In most cases, the productivity of the main crop may also be improved.
The integration of animals with permanent crops is not a simple system. The animals need to be well selected and their management carefully considered in order to obtain maximum benefits without negatively affecting the production of the main crop.
Some efforts have been made to define the methodology required for a multidisciplinary approach to integrated systems (Iñiguez and Sánchez, 1991; Shelton and Stür, 1991). However, there is a need to define much better the research methodology in order to evaluate the effects on the various system components. The comparative advantages of various species need to be studied for the different systems; for example, identifying a forage species that can be used as cover crop for orange plantations for sheep to graze on. Above all, the protection of the environment and sustainability should be essential objectives of all agricultural systems.
Arope, A.N., Tajudin, I.B. & Chong, D.T. 1985. Sheep rearing under rubber. Planter, 61: 70-77.
Borroto, A., Bello, T., Cobas, M., Valdespino, A. & Hernández, L. 1986. Factibilidad de producir carne o vina en areas citrícolas. ACPA (Cuba), p. 53-56.
Borroto, A., García, del Carmen, M., Cruz, D. & González, O. 1985. Resultados preliminares sobre crianza ovina utilizando la hierba de los cítricos. Rev. Prod. Anim. (Cuba), 1(2): 15-20.
Borroto, A., Molina, A., Cruz, D. & Pérez, C. 1989. Potencial alimentario de los subproductos agrícolas de cítricos: hierbas bajo corta mecanizada y para la producción de carne ovina. Rev. Prod. Anim. (Cuba), 5(2): 131-136.
Chen, C.P. 1991a. Cattle productivity under oil palm in Malaysia. In H.M. Shelton & W.W. Stür, eds. Forages for plantation crops, p. 97-101. Proceedings of a workshop, Sanur Beach, Bali, Indonesia, 27-29 June 1990. ACIAR Proceedings No. 32.
Chen, C.P. 1991b. Management of forages for animal production under tree crops. In L. Iñiguez & M. Sánchez, eds. Integrated tree cropping and small ruminant production systems. Proceedings of a workshop on research methodology, Medan, Sumatra, Indonesia, 9-14 Sept. 1990.
Chen, C.P., Wong, H.K. & Dahlan, I. 1991. Herbivores and the plantations. In Y.W. Ho et al., eds. Recent advances on the nutrition of herbivores, p. 71-81. Proceedings of the Third International Symposium on the Nutrition of Herbivores. Serdan, Elangor Darul Ehsan, Malaysia, Malaysian Society of Animal Production.
Dalla Rosa, K.R. 1993. Cattle under coconuts: a practical Pacific tradition. Agroforestry for the Pacific Technologies. Paia, Hawaii, USA, Nitrogen Fixing Tree Association.
García, E., Naranjo, R., Hernández, B. & Fernández, D. 1989. Evaluación de un sistema de máquinas para la elaboración de heno en las calles de naranja Valencia en producción. Rev. Prod. Anim. (Cuba), 5(2): 191-196.
Iñiguez, L. & Sánchez, M., eds. 1991. Integrated tree cropping and small ruminant production systems. Proceedings of a workshop on research methodology, Medan, Sumatra, Indonesia, 9-14 Sept. 1990.
Leyva, D., Lima, H. & Alvarez, E. 1990. Algunos aspectos sobre el pastoreo y utilización de las ocas. Centro de Información y Documentación Agropecuarios, La Habana, Cuba. 20 pp.
Mukherjee, J.K., ed. 1992. Integrated livestock-fish production systems. Proceedings of an FAO/IPT workshop on integrated livestock-fish production systems, 16-20 Dec. 1991, Institute of Advanced Studies, University of Malaysia, Kuala Lumpur, 148 pp.
Preston, T.R. & Murgueitio, E. 1992. Strategy for sustainable livestock production in the tropics. CIPAV-SAREC, Cali, Colombia. 100 pp.
Reynolds, S.G. 1988. Pasture and cattle under coconuts. FAO Plant Production and Protection Paper No. 9. Rome, FAO. 321 pp.
Sánchez, M.D. & Ibrahim, T.H. 1991. Forages species for rubber plantations in Indonesia. In H.M. Shelton & W.W. Stür, Forages or plantation crops, p. 54-57. Proceedings of a workshop, Sanur Beach, Bah, Indonesia, 27-29 June 1990. ACIAR Proceedings No. 32.
Sánchez, M.D. & Pond, K.R. 1990. By-pass protein for growing lambs grazing under rubber plantations. In USAID Small Ruminant Collaborative Research Support Program. Annual Research Report 1989-90, Sei Putih, North Sumatra, Indonesia. 26pp.
Sánchez, M.D. & Pond, K.R. 1991 Nutrition of sheep that are integrated with rubber tree production systems. In L. Iñiguez & M. Sánchez, eds. Integrated tree cropping and small ruminant production systems, p. 97-108. Proceedings of a workshop on research methodology in Medan, North Sumatra, Indonesia, 9-14 Sept. 1990.
Shelton, H.M. & Stür, W.W. 1991. Forages for plantation crops. Proceedings of a workshop, Sanur Beach, Bali, Indonesia, 27-29 June 1990. ACIAR Proceedings No. 32. 168 pp.
Skerman, P.J., Cameron, D.G. & Riveros, F. 1988. Tropical forage legumes. FAO Plant Production and Protection Paper No. 2. Rome, FAO. 692 pp.
Speedy, A. & Puglièse, P.L., eds. 1992. Legume trees and other fodder trees as protein sources for livestock. Proceedings of an FAO Expert Consultation held at the Malaysian Agricultural Research and Development Institute, Kuala Lumpur, Malaysia, 14-18 Oct. 1991. FAO Animal Production and Health Paper No. 102. Rome, FAO. 339 pp.
Tajuddin, I. & Chong, D.T. 1991. Sheep grazing to manage weeds in rubber plantations. In L. Iñiguez & M. Sánchez, eds. Integrated tree cropping and small ruminant production systems, p. 128-135. Proceedings of a workshop on research methodology in Medan, North Sumatra, Indonesia, 9-14 Sept. 1990.
Vera y Vega, A. 1986. Alimentación y pastoreo del ganado ovino, p. 189-217. Monografías N° 87. Universidad de Córdoba, Córdoba. (Los recursos pastorales españoles y su aprovechamiento.)
Wong, C.C. 1991. Shade tolerance of tropical forages: a review. In H.M. Shelton & W.W. Stür, Forages or plantation crops, p. 64-69. Proceedings of a workshop, Sanur Beach, Bali, Indonesia, 27-29 June 1990. ACIAR Proceedings No. 32.
