Brazil - part II
back to introduction
Aiming to present the Brazilian pasture resource in a clearer and more organized way, and since Brazil has continental dimensions, the description will be made according to different officially recognized Brazilian biomes (see Plate 6).
Amazônia Forage Profile
Amazonian soils are characteristically very acid, with extremely low P levels and low CEC, besides other mineral deficiencies (Peixoto et al., 1986). The high P fixing capacity of those soils contributes to reducing opportunities for pasture development. Guineagrass and Hyparrhenia rufa are more responsive to P than Brachiaria humidicola, and tropical legumes may be more tolerant than the grasses to lower levels of P. Lowland grasslands are inundated periodically; species of Echinochloa, Hymenachne, Oryza, Leersia, Luziola and Paspalum, cover poorer soils over huge areas. The problem of these areas is the absence of adjacent land to graze the animals during the floods, so animals lose weight due to nutritional and health constraints.
The upland grasslands, which represent around 60% of the region, display a similarity in botanical composition, where Andropogon spp., Axonopus spp., Trachypogon spp. and Paspalum spp. set the productivity and forage quality. Also important are the legumes of Pueraria spp., Centrosema spp. and Dolichos spp. Arachis is recently increasing in importance in some areas. This ample substrate produces poorer quality forage than the lowland grasslands. Within those grasslands nutrient cycling is the driving force for their sustainability. Burning and the high grazing pressure are critical to attain it.
After clearing sections of the tropical rain forest, pasture development brought significant ecological changes to the environment. Initially there was an increase in soil fertility due to the ashes. The rapid establishment of guinea grass, Brachiaria humidicola and Andropogon gayanus pastures encouraged intensive grazing and within three years signs of degradation were evident. But more leniently grazed pastures could be maintained for more than ten years. The P levels of these soils imposed limitations on pasture productivity, although some regional authors (e.g., Dias Filho & Andrade, 2005) showed five to six fold (up to 25 - 36 tons DM ha -1) increases in pasture response of the upland areas when fertilized and sown to cultivated species.
The level of phosphorous, and its decrease following establishment, and overgrazing are the most important factors in pasture degradation, a problem verified in 61.5% of the Amazonian Occidental cultivated pastures; according to local authors (e.g., Dias Filho & Andrade, 2005) an area estimated at around 12,500,000 ha is affected. Spittle-bug and disease are also important in contributing to pasture degradation, as well as the indiscriminate use of fire.
In site-specific Amazonian areas, there are success stories with the use of grass-legume mixtures. Pueraria, the most impressive, accounts for more than 450,000 ha, being present in more than 30% of pastures in the State of Acre.
Since 1995 the cultivated pasture area increased almost 70%, being estimated at almost 57 million ha by 2003. Cattle stocks increased from 19.18 to 33.93 millions in the same period, illustrating the concerns about ecosystem conservation. As this region presents currently the highest Brazilian livestock expansion, and at the same time is characterized by low research investment (financial and human resources), it is of great concern for the future (Dias-Filho & Andrade, 2005).
Cerrado Forage Profile
In the last 25 years the green revolution was initiated and most of the "Cerrados" vegetation has been replaced by agriculture and after one or two years of growing crops, the land was turned into sown tropical pastures. Stocking rates were increased several fold, from 0.3 to 1.0 head/ha (Macedo, 1997). Brachiaria spp is the most widespread genus, covering more than 50,000,000 ha (see Plate 8) of the tropical savannah, representing 85% of cultivated pastures. B. decumbens (15 million ha) and B. brizantha (30 million ha) are the most cultivated pastures (Macedo, 2005). Panicum (see Plate 9) is the second most important genus, representing 12% of cultivated pastures or 7.2 million ha. Pasture establishment and/or regeneration being integrated with crops is now well adopted.
Low forage availability and quality in the dry season are the main limiting factors, lengthening the productive cycle in cattle raising. Burning is common. Deferment is sometimes used and constitutes one of the rare technologies employed in the most extensive areas. No more than 1-2% of cultivated pastures are legume-based, the genus Stylosanthes being the most important. For most of the area, there was no technological support to ranchers who stay away from agricultural administration, and livestock were practically raised by nature.
Pasture degradation is considered the most important phenomenon facing the sustainability of livestock production in Cerrados, with overstocking and the lack of maintenance fertilization considered the main problems.
Mata Atlântica Forage Profile
Most of the dairy production is based on pastures developed on cleared pasture-land, where Melinis minutiflora predominated on the poorer soils of steep slopes, whose forage mass was of acceptable nutritive value, but had a low carrying capacity. Pennisetum purpureum is another important forage in dairy areas. Pastures based on Hyparrhenia rufa were persistent, but their productivity was also low. On some of the remaining fertile soils, Panicum maximum had thriven and is still the main beef pasture for the region. In the last 20 years the Brachiaria sp. took over and Brachiaria brizantha cv. Marandu is being strongly recommended due to its resistance to spittle-bug disease (Deois flavopicta and Manarva sp.). Cultivated pastures can provide conditions for high levels of animal productivity (25 to 30,000 kg milk/ha per year and 1,000 to 1,600 kg LWG/ha per year in well fertilized soils, producing more than 30,000 kg DM during the growing season. Digitaria decumbens, Brachiaria decumbens and Brachiaria humidicola are still important locally.
Like the "Cerrados", eastern Brazil makes low usage of fertilizers for introduced pastures that are grazed at high stocking rates, so the high grazing pressure causes a weakening, and these pastures soon degenerate. Pasture degradation is an important limiting factor for farmers. Tropical legumes are scarcely used, and the highly seasonal dry matter production does not balance forage quality with animal needs. There is a feed shortage during the winter dry season (April/September), when supplementation is sometimes used, particularly in dairy systems. Intensive management of highly productive cultivated pastures is the most significant technology, but is still weakly adopted.
Caatinga Forage Profile
The main genus for the region are Mimosa, Caesalpinia, Dalbergia, Paspalum, Setaria, Cenchrus, Aristida, Elionorus, Zornia, Stylosanthes, Centrosema and others. In the short rainy season the herbaceous vegetation and green leaves of trees compose the forage mass. The Caatinga phytomass annual mean production is around 4.0 t/ha and dicotyledon herbaceous and grasses make up 80% of the ruminant diet, but in the dry period the importance of woody species increases. With the onset of the long dry season the leaves of the trees become dry and fall to the ground and are eaten by livestock. By the middle of the dry season 62% of their diet is composed of dead leaves of woody vegetation and up to 28% is from the standing herbaceous vegetation. Early in the rainy season, green leaves of trees comprise 65% of the diet and the herbaceous vegetation the other 35%. These prolonged droughts have a greater impact on the cattle population than on goats and sheep, since they are better adapted to adverse conditions.
Due to the importance of trees in the diets of grazing animals, manipulation of the vegetation is very important, and it is a common practice to pollard (cut the old branches of the trees and the top of the trunk) to develop new sprouts and branches from where the goats get most of their feed. Thinning of the stand is also done, and gradually they get trunk heights of less than 0.50 m from the ground, when all leaves are within reach of the animals, increasing the foraging substrate. Under natural conditions of the "Caatinga" vegetation, mixed grazing of cattle, sheep and goats is more productive. By thinning the vegetation, cattle and goats are favoured. But when that canopy is manipulated, and the trunks are cut close to the ground for new branching, cattle alone or cattle and sheep make better use of these natural resources. In areas of higher rainfall the main cultivated grasses are Cenchrus ciliaris and Brachiaria spp, Andropogon being less important. Important considered plants to face the semi-arid conditions of Caatinga and feed animals are “palma forrageira” (Opuntia spp.), sugar cane, sorghum and manioc. During prolonged drought periods, cattle are first supplemented, then sheep. Goats are supplemented only at very critical conditions. Young and non productive animals are free-ranging the Caatinga to find the remaining forages.
Pantanal Forage Profile
Pampa (Campos) Forage Profile
The most important cultivated forages are annual winter grasses like Avena strigosa and Lolium multiflorum (Nabinger et al., 2000), as well as legumes of the genera Trifolium, Lotus, Medicago and others. Tropical pasture species are mainly annuals, such as Pennisetum americanum, and Sorghum spp., but perennials are becoming important (Panicum, Cynodon, Digitaria, Paspalum, other Pennisetum, etc.). To a lesser extent, some perennial winter grasses are cultivated (Festuca, Phalaris, Dactylis, etc.). Cultivated pastures comprise around 7,000,000 ha, while native pastures attain 13,700,000 ha. So native pastures feed most of the 26,200,000 cattle and 6,000,000 sheep. Cattle and sheep are mainly raised in mixed-grazing on the native pasture areas. In Southern Brazil this natural ecosystem is under threat, decreasing at a rate of 135 000 ha per year (Nabinger et al., 2000), being replaced mainly by cash crops and reforestation. It is the basic habitat for 3 000 vascular plants, 385 species of birds and 90 terrestrial mammals. More than 50 forage species have been classified recently as in danger of being extinguished by mismanagement of natural resources. Overgrazing and lack of nutrient replacement are mainly responsible for the weak sustainability of the system.
Traditional pastoralism predominates in the use of these pastures, and feed is used mostly for maintenance purposes. This region is the second most productive in Brazil in terms of volume of milk. Integrated crop-animal production systems are becoming an interesting option mainly in summer crop areas with soybean, maize or rice.
(also see Maraschin, 2001 for this topic)
Greater Use of Legumes
In many regions of Brazil there are ample opportunities to use forage legumes, since they are endemic to the area. Tropical legumes are also important in restoring lands degraded by imprudent cropping or grazing. These pastures, although contributing, are often unstable, and the management necessary to maintain an adequate proportion of legume is still little understood. The efforts devoted to selecting grass and legume germplasm adapted to the acid soils found in important ecosystems such as savannahs and humid tropical forests, revealed that S. capitata and S. guyanensis are suitable for the savannahs and the humid tropical rain forest, and Arachis pintoi is compatible with aggressive and stoloniferous grasses and is very persistent under heavy grazing. Pueraria phaseoloides and Stylosanthes capitata which animals select in the dry season also show potential for the tropical rain forest environment. Development of technologies for local seed production to supply legume based forage systems was important. Evaluations under grazing yielded results from 200 - 400 kg LW ha -1 in locations with dry-season stress, and up to 500 - 600 kg LW ha -1 in areas with no dry-season stress.
For other marginal areas, in the two storey vegetation of herbaceous plants and Acacia caven, the deciduous foliage of the trees replenished the soil minerals removed by the grazed herbaceous plants. Even with the lush growth of the trees, the herbs under that shading were luxuriant relative to those under full sunlight. The trees got most of the water they need from deeper soil layers, allowing more for the herbaceous vegetation that explores the upper layers of the soil. Lots of similarities are also found in the northeast within the "Caatinga" vegetation.
The spectacular increase in individual animal performance when grazing legume-based cultivated pastures compared with native savannah grassland deserves mention. It is hoped that legumes will contribute with low-cost nitrogen to the associated grass. This characteristic and the tolerance to low fertility and acid soils are always major themes of research and the first objectives pursued. The problem is that Brazilian grazing history with large herbivores is short and these legumes have, in general, very limited adaptations to tolerate heavy grazing, having more specialised escape mechanisms; this deserves more attention by forage breeders.
Managing Grazing Intensities
It has long been known that lower grazing pressure, or high herbage allowance, allows very high levels of animal performance from either natural or cultivated tropical pastures. Values range for natural pastures: 0.69 - 1.0 kg an-1 day-1 and for cultivated tropical pastures: 1.5 - 1.27 kg an-1 day-1. This should encourage grazing management practices that use lighter grazing intensities on native or tropical cultivated pastures, but unfortunately this is not the case in commercial situations.
Managing Grazing Intensities on Native Pastures
The ranching philosophy of pasture utilization predominates in the use of natural pastures despite the strong support from research results. Grazing efficiencies greater than 50% occur at daily herbage allowance levels from 13 to 18 kg DM 100 kg LW-1 with peak efficiencies occurring from 6 to 9 kg DM 100 kg LW-1. Daily herbage allowance values below 20 kg AU -1 allow for 4.4 kg DM per 100 kg LW and restricted the intake of a 454 kg mature cow.
It has also been suggested that deferring grazing to recover or rejuvenate these native pastures and to increase the biomass productivity and the frequency of the desirable species for the site, would be beneficial. Reduction in stocking rate and sowing cultivated species is an alternative. By reducing stocking rate one slows down the rate of degradation but not the trend toward degradation, since the grazing animals will continue to overgraze the preferred species selectively within plant communities. This is an ever present phenomenon, and can be a critical one, where pasture biodiversity is not counterbalanced by different species of grazing animals. On the other hand, the introduction of cultivated species is feasible once there are provisions against the limiting factors that might jeopardise the new pasture, especially fertilization.
The distinct pasture canopies can range from prostrate forms of growth under heavier grazing pressures, to rank vegetation under more lenient management. Tufted grasses may represent a forage resource depending on the availability of preferred species, and so the concept of “forage” itself may be quite variable, and represents an additional challenge to the characterization of the grazing environment and to pasture utilization. An accumulation rate up to 16.3 kg DM ha -1 day -1 through the season for natural pastures maintained at an optimum stocking rate was determined to be at a herbage allowance of 13.5% LW per day, which was equivalent to maintaining the herbage mass at a level of 1,400-1,500 kg DM ha -1. The conversion efficiency of this ecosystem in capturing radiation energy from sunlight to transform it into primary production ranges from 0.20% for high grazing pressures to 0.36% at appropriate ones, which represented an 80% increase in system efficiency. This demonstrates the important improvements that can be made simply by managing this pasture ecosystem at the correct grazing intensity. These values and relationships mean that the productivity of these grasslands can be 100% increased at a cost of harvesting forage by the grazing animal, with no other energy input than thought.
Carvalho (unpublished) summarises the main current knowledge about natural pasture management in southern Brazil, as follows:
Managing Grazing Intensities on Cultivated Pastures
It is recognised that improved pastures have been shown to greatly increase rates of animal production. For example, very interesting was the assessment concerning Cenchrus ciliaris, introduced into the native pastures of the dry-NE Brazil, promoting a two fold increase in the LWG ha -1, but with no changes in the average daily gain per animal (ADG an -1).
When dealing with productivity the entire system has to be considered, with both seasonal and annual variations included. There is evidence that an increase in ADG an-1 under grazing is the best way to reduce animal production costs, showing that animals per hectare express the rate of stocking that allows for the optimum individual animal performance.
The results from central Brazil and the "Cerrados" indicate that persistency of cultivated pastures depends on initial soil fertility and lenient grazing management. Lenient grazing is important, but not enough for pasture sustainability. The decline in soil fertility status is the starting point of pasture degradation. The first symptom observed is the reduction in carrying capacity under equivalent forage allowance; the pasture regrowth does not acquire its previous status after resting; and the reduction in forage mass and quality reduces ADG an-1. Bare spots become visible in the pasture, weeds invade and some native species return. So, judicious monitoring of carrying capacity would indicate the beginning of the degradation process. When detected early it may cost 100US$ ha-1 to recover the area, while later detection raises costs to 200US$ ha-1. Reducing the stocking rate helps to maintain animal performance but does not overcome the trend in pasture degradation.
Another choice that is acquiring importance is the integration of crop and grassland agriculture within a complete system of land use and farm productivity. The annual crops will generate financial resources for improving the soil fertility level, thus reducing the costs of pasture establishment. Consistent results are showing new pastures with increased pasture potential for the region, where fertilized Panicum pastures are producing 740 kg LW ha -1 year -1, while the Brachiaria sp. reach a ceiling yield at 600 kg LW ha -1 year -1. These differences come from the higher ADG an -1 and higher number of steers carried by the Panicum, compared to Brachiaria pastures. For enterprises adopting low levels of technology, Brachiaria is the option, while for those adopting the existing high level of technology, Panicum pastures are recommended.
New experimental results with Brachiaria cultivars showed different rates of leaf growth for the wet and the dry seasons. Some ecotypes displayed higher leaf DM yield in the dry season while others performed better for the wet season, and were recommended to be tested for animal gains. They have already shown high pasture potential. Hopes rest on the animal potential of those new varieties.
The promotion of grazing based on the green leaf lamina dry matter (GLLDM), contributes to our knowledge and understanding of what happens in the pasture profile, to evaluate pasture dynamics and to watching the shaping up of the silhouette of a steer gaining weight and being finished on pasture under grazing. At low levels of GLLDM the animals graze more frequently, promote tiller density as well as invasion of other plant species, and adversely affect root mass, plant diameter, internode length, tiller weight, rate of accumulation of GLLDM and total GLLDM yield. It seems that heavy grazing does not help the pasture.
With clearly defined levels of pasture GLLDM management being applied to Mott dwarf elephantgrass, studies reveal that a sustainable optimum ADG of 1.043 kg an-1 at a herbage allowance of 10.5% LW day -1 of GLLDM yielding 1,188 kg LWG ha -1 can finish a slaughter steer within 210 days of grazing, under continuous stocking.
Based on the acquired knowledge in conducting grazing experiments to evaluate herbage allowance and animal and pasture responses, it is suggested that at least 1,500 - 2,000 kg ha-1 of live green leaf lamina DM of the forage mass is required from which the grazing animals will get their diet.
Sward targets: a recent orientation for grassland management (see Silva & Carvalho, 2005)
The tropical/sub-tropical environment is unique, requiring creative and site-specific solutions to overcome production constraints in order to realise its potential. The range of plant species, their varying size, morphology and physiology highlight the need to review some of the concepts and general views relating to animal performance from these pastures. Recent experimental work on pasture ecophysiology and grazing ecology in Brazil has been conceived under the conviction that control, monitoring and manipulation of sward state is an important feature of grazing management. This is very different from the traditional and simplistic view of production, in which control of the grazing process is made by means of fixed stocking rates, herbage allowances, grazing intervals and grazing method and allows for significant variation in sward state.
New work is in progress in Brazil for the main forage resources (e.g., Brachiaria, Panicum, Cynodon, Pennisetum, etc.) about how sward structure is built and how animals capture forage from these structures. As a consequence of this new knowledge, and aiming to optimize pasture production (i.e., light interception) and animal intake (i.e., animal performance), some very recent sward guidelines are being recommended, some of which are illustrated below:
Recent evidence generated under these conditions demonstrates that well fertilized and managed tropical/sub-tropical forage species can produce herbage of sufficiently high quality to ensure satisfactory animal performance throughout the year. Low quality herbage during the winter period can be a result of inefficient harvest during previous favourable growing seasons and is not necessarily an intrinsic characteristic of the herbage produced. Additionally, non-nutritional factors (e.g., sward structure) have a greater relative importance than nutritional factors regulating herbage intake of grazing animals.
Animal production systems for tropical/sub-tropical pastures have an additional and significant constraint, i.e. the pronounced seasonality of herbage production. This generates variation in the feed supply-demand balance of the system between and within seasons of the year, which must be managed if sward control is to be achieved effectively. Management practices have direct and indirect impacts on sward control, structure and animal performance that need to be known in order to allow for the correct planning and decision making process on a farm scale. Consequently, the current research and the management orientation for tropical/sub-tropical grasslands are being based on the careful control and planning of sward state.
In a classical experiment done in southern Brazil, phosphorous was applied broadcast in a natural pasture (160 kg ha-1), and continuous versus rotational grazing was under evaluation. After 11 years of grazing, there was a 10% increase in livestock production from rotational grazing compared with continuous stocking. However, the outstanding response was to P fertilization, which showed an increase in productivity of around 4.95 kg LWG ha-1 kg-1 of applied P. After 11 years the fertilized natural pasture was producing 70% more than the unfertilized natural pasture. No doubt, there was a very lasting and contributing effect of the P application.
To illustrate the possibility of changing botanical composition by fertilizers and altering the quality status of pastures, a trial has shown that Desmodium incanum increases from 3.3% up to 24.4% in a pasture as a result of high phosphorus applications in southern Brazil. With regard to nitrogen, when a natural grass such as Paspalum notatum is fertilized and water doesn’t limit growth, pasture production reaches 12.0 tons DM ha -1, and places doubt on the necessity for cultivated pastures. This information has had a considerable impact on the southern research programmes resulting in the promotion of native pasture fertilization at medium levels for pasture sustainability.
Maintenance of soil nutrient status is a key variable in pasture sustainability. There are sharp residual effects of P fertilization on forage DM production of subtropical pasture mixtures, with increased legume contribution as the P levels are increased. However, the P levels in the soil are gradually being reduced due to extraction by plants when there is no P replacement, and after five years phosphorous can be reduced to 1/5 of what it was at the beginning.
Annual fertilization of a mixture of guinea grass, Siratro, Glycine wightii and Stylosanthes guianensis on the other hand, kept that pasture productive for more than ten years. The annual application of 20 kg ha-1 of P helped in maintaining pasture production while the application of 40 kg ha-1 of P increased the pasture production by 30%, whereas under no fertilization production dropped at a rate of 15% annually. Panicum spp. were also identified as responsive to fertile soils, where high levels of P were applied, while Stylosanthes capitata, Stylosanthes guianensis and Zornia spp. with Brachiaria humidicola, Hyparrhenia rufa and Andropogon gayanus were identified as species with good performance on soils with low P supply. Researchers thus emphasized the development of a philosophy of pasture productivity to take advantage of fertilizer use and applied knowledge in pasture management all over the country to benefit from the improvement brought about by the fertilizer applications.
In fact, farmers do not frequently adopt fertilizer use. A 1997 survey revealed that only 663,000 tons of NPK fertilizers were annually applied to 90,000,000 ha of introduced pastures in Brazil, i.e. about 7.4 kg of NPK fertilizer/ha of pasture per year. Results from grazing trials conducted in eastern and central Brazil, in the "Cerrados" revealed that fertilization increased yield of cultivated pastures from 150 to 400 kg ha-1, irrespective of the final animal product. The search for cheap sources of nitrogen is suggested to be of paramount importance to supply pasture ecosystems and obtain livestock production at low cost.
The efficiency of P fertilization is 4.6 kg LW ha-1 kg-1 of applied P, while for N fertilization it is 1.6 to 2.0 kg LWG ha-1 kg-1 of applied N (reported for tropical pastures in central Brazil). The magnitude of responses is associated with the stocking rate, experiencing sharp declines in LWG ha-1 as the stocking rate is increased.
Supplements ( see Corsi et al., 2001)
To better utilize the standing low quality forage some farmers are feeding protein supplements (0.1% of animal live weight) containing ionophores to correct nutritional deficiencies in winter (dry and cold). While some nutrients are indeed corrected, results seem to indicate live weight gain is primarily additive rather than the supplement.
Grazing animals can also benefit from feeding supplements during the summer/autumn period. Supplementation at that time of the year aims to improve individual performance as well as the output of animal products per unit area. In dairy enterprises this strategy has been widely used and it seems that a similar average response of 1.4 kg of milk/kg of concentrate supplementation might be expected for lactating cows on temperate and tropical grasses.
For beef cattle better responses to concentrate (and possibly degradable fibre) supplement feeding seem to occur in late summer/autumn compared to the beginning of the grazing season. At this time supplemented animals grazing tropical grasses are expected to show live weight gains above 1 kg/head/day, though feed conversion is a function of the supplement type. Information regarding the synchronism between carbohydrate and protein fractions in the rumen and, consequently, the substitution of pasture DM for concentrate DM, and the high concentrate prices in tropical regions seem to be the most limiting factors restraining the adoption of supplementation programmes on the best-managed farms.
During the (wet and warm) summer, tropical pastures can support high stocking rates, peaking up to 15 AU/ha. This carrying capacity is much lower during winter, averaging 10 to 40% of summer values. Therefore the intensification of tropical pasture-based systems in summer should consider the use of conserved forages or by-products in winter to guarantee the balance between food supply and demand during the whole year. Options such as silage (maize, sorghum or perennial tropical grasses), hay (perennial tropical grasses), and several by-products (sugarcane, citrus, brewer’s grain, etc.) are available.
Feedlots during the winter are also a possibility to allow high carrying capacities on tropical grass pastures in summer. However, feedlots are economically questionable when practised on a small scale, and with high grain prices and low availability of by-products.
Recently, irrigated tropical pastures have been used to enhance carrying capacity for both beef and dairy enterprises. Production costs have been reported of about US$ 0.9/kg carcass weight in irrigated tropical pastures at the same time as selling prices were US$ 1.36/kg carcass weight. Cost analysis studies indicate that adoption of irrigated tropical pasture depends on production costs in the dry pasture system, overall production costs and selling price and the increase in productivity in the irrigated system.
Below are presented different views from research and extension, which give an idea of future possible scenarios for cattle production systems and their potential in Brazil. The following conclusion were drawn by Corsi et al. (2001):
With regard to pastures, according to Zimmer and Euclides (1997) it is necessary to develop better quality forages, which can provide a better animal performance in favourable growth periods as well as in drought. Special emphasis should be given to increase production in the rainy season when the conditions are better, improving animal performance in this way, where the available tropical pasture at present does not fulfil the genetic potential for animal gain. In dry periods the nutritional needs of some animal categories should be met using alternatives for feed supplementation, since in this period forages do not meet animal needs. It is essential that genetic improvement of forages focus on the search of legumes for animal diet improvement and, particularly, for biological nitrogen fixation. Biological N fixation is important for sustainability and for the reduction of possible environmental damage.
According to the National Agriculture Confederation [see CNA] the main demands from the beef cattle enterprise are:
(a) Genetics: selection for desirable characteristics, like precocity and biological efficiency, particularly concerning live weight and carcass; studies about volume and quantity of meat produced; production of steers with monounsaturated fat; obtaining animals with greater live weight gain in less time.
(a) Evaluation of generated products: market research to better know the final consumers.
Several organizations, mainly public, are involved in agricultural research and development. On a national scale, Federal Universities, EMBRAPA and EMATER are important institutions. At State level, we should consider the efforts of public Universities and/or Research Institutes financed by each state. Private Universities are not consolidated concerning research. Investment in scientific and technological research arising directly from Government or from research foundations can be assumed to amount to some 80 percent of the total.
The main overall research efforts are being made in the following areas: plant and animal breeding with the main focus on productivity and capacity to cope with harsh environments; technologies to rehabilitate degraded areas; grazing management focusing on intensive systems, animal nutrition focusing on feed-lot systems.
Private enterprises have recently made efforts, notably on animal genetics and plant breeding. Some of them do development work and assist farmers as a market strategy.
Some key persons and their research areas are presented (this list is not intended to be exhaustive nor definitive and it should be viewed only as a way to start contacts in the following areas):
Empresa Brasileira de Pesquisa Agropecuária: www.embrapa.br
EMATER : www.emater.tche.br/
Universidade Federal do Rio Grande do Sul: www.ufrgs.br
Universidade Federal de Viçosa: www.ufv.br
Universidade Federal de Lavras: www.ufla.br
Universidade Federal Rural do Rio de Janeiro: www.ufrrj.br
Universidade de Brasília: www.unb.br
Universidade de São Paulo: www.usp.br
Universidade Estadual Paulista: www.unesp.br
Universidade Estadual de Maringá: www.uem.br
Instituto de Zootecnia: www.iz.sp.gov.br
Fundação Estadual de Pesquisa Agropecuária: www.fepagro.rs.gov.br
Sociedade Brasileira de Zootecnia : www.sbz.org.br
Conselho Nacional de Pesquisa e Desenvolvimento Tecnológico. www.cnpq.br
Coordenadoria de Aperfeiçoamento de Pessoal de Nível Superior:www.capes.gov.br
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To prepare a Country Pasture Resource Profile for such a large and diverse country as Brazil has not been a simple task. The author wishes to thank important contributors and has much appreciated the comments received from various reviewers. Contributions are still welcome. Arrangements are being made for local revision and updating.
[The profile was prepared in April/May 2002 and was edited by S.G. Reynolds and J.M. Suttie in June 2002; it was further modified by S.G. Reynolds in October 2005, and a major revision undertaken by Paulo C. de F. Carvalho in January, 2006].