The aim of this study was to compare a silvopastoral system with a control (pasture only) in the Brazilian Cerrado. The silvopastoral system consisted of a tropical grass (Brachiaria brizantha cv. Marandu) pasture and trees (Zeyheria tuberculosa), while the control was a Marandu pasture without trees. Sheep intake, feeding behavior and microclimatic conditions were the variables evaluated. Temperatures within the silvopastoral system were lower than in the control (maximum temperature of 28 and 33.5 °C, temperature and humidity index of 74.0 and 79.2 for the silvopastoral system and control, respectively). There was increased dry matter intake (88.2 .05) in grazing sheep in the silvopastoral system relative to the control. The results suggest that a silvopastoral system would provide a more favorable environment than a straight pasture for sheep performance in a tropical grazing situation. ResumenEn el estudio se compararon un sistema silvopastoril con un sistema control de solo pastura en condiciones del Cerrado brasileño. El sistema silvopastoril consistió en una pastura de Brachiaria brizantha cv. Marandu con árboles de Zeyheria tuberculosa, mientras que el tratamiento control consistió en una pastura de cv. Marandu sin árboles. Como variables se midieron el consumo por ovejas, su comportamiento de pastoreo y las condiciones microclimáticas durante el tiempo de evaluaciones. Las temperaturas para el sistema silvopastoril fueron más bajas que en el control (temperatura máxima de 28 y 33.5 °C, e índice de temperatura-humedad de 74.0 y 79.2 para el sistema silvopastoril y el control, respectivamente). Las ovejas en pastoreo mostraron mayor consumo de materia seca (88.2 vs. 79.9 g MS/kg 0.75 peso vivo/día, P<0.05) y de materia orgánica (89.6 vs. 81.1 g MO/kg 0.75 peso vivo/día, P<0.05), mayor tiempo pastoreando (572 vs. 288 minutos/día, P<0.05), menor consumo total de agua (430 vs. 474 mL/kg 0.75 peso vivo/día, P<0.05) y menor tiempo caminando (30 vs. 89 minutos/día, P<0.05) en el sistema silvopastoril en comparación con el sistema control. Los resultados indican que para la producción ovina bajo condiciones tropicales un sistema silvopastoril puede proporcionar un entorno más favorable que un sistema de pastura sola.

T. Diversifolia can growth in acid soils including high levels of aluminium and low levels of phosphorus. 9 It is important to mention that T. Diversifolia is able to take mobilized phosphorus from the soil to the plant, which is a positive characteristic for most of tropical soils. It requires 800 to 5.000mm of water, 16 to 30°C and can growth from sea level to 2.500m altitude. 9 Usually, T. Diversifolia occurs in marginal area as of roads, around crop fields and hedges or close to farm houses. In Latin America and Caribbean (Colombia, México, Cuba, Panama, Dominican Republic and Brazil) pure stands are growing fast as farmers start to recognize the high biomass production and nutritional value of the plant. Usually, T. Diversifolia is propagated from stem cuttings of 20 to 40cm length, inserted vertically into the soil, 10 to 20cm deep. Seeds can also be used as they germinate under the canopy or even in plastic bags, and then seedlings transplanted to other areas. The main benefit of this method is that the roots will grow deeper in the soils, compared to vegetative method, and the growth is improved. However, the biomass production is influenced by soil quality, planting methods, cutting frequency, stand density and weather. 9,12,13 Although it has been used as a fodder for animal nutrition, 4,7,8,14 there are several uses reported for T. Diversifolia like insect repellent and negative effect against ants, 15 allelopathic effect against other plants, 16,17 source of nectar for bees 18 and sources of nutrients (N, P and K) for degraded soils as the biomass is quickly decomposed and consequently nutrients are easily released to the soil. 2,19 Nutritive value The studies developed by The University of Sao Joao del-Rei-Brazil (UFSJ) and CIPAV (Colombia) showed promising results for the use of T. Diversifolia as forage for ruminant nutrition. The chemical constituents of whole plant, leaves and stem obtained during the booting and pre-flowering stage when plant height reached 0.80-1.0m from the soil are good examples of important elements that could provide positive evidences of the nutritional values of T. Diversifolia. 20 The total dry matter (8.1ton/ha for booting and 5.6t/ha for pre-flowering) and fresh production (41.3ton/ha for booting and 24.7t/ha for pre-flowering) of whole plant were also included (alley crop system). The protein values during the booting (164.7g/kg DM) were higher compared to pre-flowering (149.1g/kg DM) stage. These values are as high as the values observed in some tropical legumes like, Stylosanthesguianensis (162.0g/kg DM), 21 Arachispintoi (180.0g/kg DM) 22 Gliricidia sepium (139.0g/kg DM) 22 and are higher

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