-The objective of this study was to evaluate the mass of the forage and of the morphological components, and the sward structure in Piata palisadegrass (Brachiaria brizantha cv. Piata) deferred in function of different initial heights and nitrogen levels. Two levels of nitrogen (75 and 150 kg/ha) and one control without fertilization associated to three initial deferring heights (20, 30, and 40 cm) were evaluated. The design was of completely randomized blocks with three replications in a subdivided plot scheme. A raise in the initial deferment height and in the fertilization elevated the sward and extended tiller heights, the leaf area index, and the light interception by the sward. The piata palisadegrass deferred with an initial height of 40 cm presented a higher forage mass with lower percentage of leaf blades, and higher stem and dead tissue quantity.Additionally, this management strategy resulted in lower bulk density of leaf blade and in higher bulk densities of stems and dead tissue. The utilization of 150 kg/ha of nitrogen raised the production and the bulk density of deferred piata palisadegrass forage and increased production and bulk density of leaves and stems. In the region of Viçosa, Minas Gerais, the piata palisadegrass deferred with an initial height of 30 cm and fertilized with 75 kg/ha of nitrogen in the beginning of the fall presents adequate mass and structure to animal production in the winter.

-The objective of this study was to determine the deferment period and the most adequate initial sward height of Brachiaria brizantha cv. Piatã for deferment in the region of Viçosa, Minas Gerais. For so, the following characteristics were evaluated: masses and bulk density of forage and its morphological components, light interception by the sward, leaf area index, leaf angle, sward and extended tiller height and falling index of the deferred piatã grass. The three deferment periods assessed (65, 85 and 105 days) were randomized to the plots and the three sward heights (20, 30 and 40 cm), randomized in the subplots. The experimental design was of completely randomized blocks, with three replicates, in a subdivided plots arrangement. Masses of forage, green stem and dead tissue were higher in the piatã grass managed with deferment period of 105 days. The mass of green leaf blade was higher in the piatã grass deferred with 20 cm height associated to the deferment period of 85 days, which had, as consequence, greater bulk density of green leaf blade. The interception of light by the sward was greater in the piatã grass kept longer in deferment associated with the higher leaf area index, regardless of its initial height.The heights of the sward and extended tillers were greater in the piatã grass under periods of 85 and 105 days of deferment; however, the falling index was not affected by the factors studied. In the region of Viçosa, Minas Gerais, B. brizantha cv. Piatã fertilized with 75 kg/ha nitrogen and deferred with initial height of 20 cm and for a period of 85 days, from mid April, has adequate productivity and structure for animal production.

RESUMO. Objetivou-se identificar, pela avaliação do perfilhamento, as estratégias adequadas de manejo da Brachiaria decumbens cv. Basilisk em lotação contínua com bovinos. Foram estudadas duas estratégias de manejo: pasto com 25 cm de altura durante todo período experimental, e pasto com 15 cm no inverno e 25 cm na primavera e verão. Foram adotados o esquema de parcelas subdivididas e o delineamento em blocos casualizados com quatro repetições. As estratégias de manejo foram o fator primário e as estações (inverno, primavera e verão), o fator secundário. O menor balanço entre taxas de aparecimento (TApP) e de mortalidade de perfilhos (TMoP) e o menor número de perfilho vegetativo ocorreram no inverno. Na primavera e verão, o balanço e o número de perfilhos vegetativos foram altos e similares. O rebaixamento do pasto no inverno incrementou o balanço entre TApP e TMoP e o número de perfilhos, em relação à sua manutenção em 25 cm. Houve maiores números de perfilhos reprodutivos e mortos no verão e no inverno, respectivamente. Os pastos com 25 cm possuíram maior número de perfilho morto. Em lotação contínua, o rebaixamento da B. decumbens para 15 cm no inverno e sua manutenção em 25 cm na primavera e verão otimiza sua renovação de perfilhos.Palavras-chave: altura do pasto, Brachiaria decumbens, estação do ano, manejo sazonal, pastejo. ABSTRACT. Tiller number in signalgrass under continuous stocking systems.The study was conducted to identify, through assessments of tillering, appropriate management strategies for Brachiaria decumbens cv. Basilisk under continuous stocking with cattle. Two management strategies were studied: pasture with 25 cm throughout the experimental period, and pasture with 15 cm in winter and 25 cm in spring and summer. A split-plot and randomized block design with four replications were adopted. The management strategies represented the primary factor, and the seasons (winter, spring and summer) were the secondary factor. The lowest balance between rates of appearance (TAR) and mortality (TMR) of tillers and the lowest number of vegetative tillers occurred in winter. In spring and summer, the balance and number of vegetative tillers were higher and did not differ. The lowering of pasture in winter resulted in greater balance between TAR and TMR and higher number of tillers in relation to management on sward fixed at 25 cm. There were greater numbers of reproductive and dead tillers in summer and winter, respectively. The pastures with fixed height of 25 cm contained a higher number of dead tiller. Under continuous stocking, the lowering of B. decumbens pasture in winter and its increase to 25 cm in spring and summer optimizes turnover of tillers.

-This study was conducted to evaluate the defoliation patterns on B. decumbens cv. Basilisk (signalgrass) tiller as a function of influence of feces deposited naturally by cattle. The signalgrass was managed with an average height of 25 cm, under continuous stocking and variable stocking rate. Interval and intensity of defoliation, grazing efficiency and forage loss were evaluated in two sites on pasture -one close and the other distant from feces. The completely randomized block design with three replications was adopted. The defoliation rate of the pasture site close to feces was 40% lower than at that distant from feces. This response pattern was similar to defoliation intensity of leaf blade. The leaf blade of the tiller close to feces also achieved lower de foliation (1.64) than that in the tiller distant from feces (3.97). The relative number of grazed leaf per tiller in the tillers distant from feces was approximately 185% higher than those close to feces. The grazing efficiency was lower in the local close to feces compared with that distant, unlike forage loss. The natural deposition of feces by cattle modifies the grazing and use patterns of B. decumbens under continuous stocking.

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