RESUMO: O objetivo do trabalho foi avaliar a estrutura do dossel e o desempenho de ovinos durante a estação seca em resposta ao manejo adotado nas águas em pastos de capim-massai. Os tratamentos consistiram do arranjo fatorial 2 x 2, duas metas de interceptação de luz (90% e 95%) e duas alturas de pós-pastejo (15 e 25 cm). Os manejos foram realizados no período chuvoso enquanto que no período seco o pasto foi manejado sob lotação contínua. No pasto foi avaliada a altura do dossel, massa de forragem, massa de lâmina foliar, massa de colmo, massa de material morto, relação lâmina foliar:colmo, os teores de proteína bruta, fibra em detergente neutro, fibra em detergente ácido, lignina em detergente ácido dos componentes morfológicos. Foram utilizados 16 ovinos com peso corporal inicial de 19 ± 4,7 kg, e avaliado o ganho de peso médio diário, o ganho de peso por hectare e a taxa de lotação. As interações entre as fontes de variações não foram significativas para nenhuma das variáveis. As alturas de pós-pastejo modificaram as massas de forragem total e de material morto na época de seca, quando manejados nas águas a 25 cm foram observados os maiores valores de 2912,5 e 1840,9 kg/ha de matéria seca, respectivamente. Não houve efeito dos manejos adotados no período das águas na composição química das lâminas foliares no período seco. Não foram observadas efeito dos manejos adotados no período das águas sobre o desempenho animal no período seco. Os pastos manejados com altura de pós-pastejo de 25 cm na época das águas, independente das metas de pré-pastejo, 90% ou 95% de interceptação de luz, mantém a estrutura mais adequada ao pastejo durante a época seca. Os manejos adotados na época das águas não interferiram no desempenho e produtividade dos animais.Palavras-chave: composição química, ganho de peso, Panicum maximum, taxa de lotação. FORAGE STRUCTURE AND PERFORMANCE OF SHEEP RAISED ON MASSAI GRASS DURING THE DRY SEASON IN RESPONSE TO WET SEASON MANAGEMENTABSTRACT: The objective of this study was to evaluate the canopy structure and performance of sheep raised on massai grass during the dry season in response to the management adopted during the wet season. The treatments consisted of two targets of light interception (90 and 95%) and two post-grazing heights (15 and 25 cm) in a 2 x 2 factorial scheme. Pastures were managed during the wet season, while continuous stocking was used during the dry season. The following pasture characteristics were evaluated: canopy height, forage mass, leaf blade, stem and dead matter mass, leaf blade:stem ratio, crude protein, neutral detergent fiber, acid detergent fiber and acid detergent lignin content, and dead matter of morphological components. Sixteen sheep with an initial body weight of 19 ± 4.7 kg were used and average daily gain, weight gain per hectare and stocking rate were evaluated. The interactions between sources of variation were not significant for any of the variables. Post-grazing heights modified total forage and dead matter mass in the dry season, with

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Identifying forage species that are responsive in regions with marked water deficits is one of the greatest challenges for the sustainable development of agriculture. However, information is still lacking about the persistence response of those pastures and their abilities to produce new tissues at the times of water scarcity. We hypothesized that Brachiaria grass has a tillering capacity during water-stress periods. This study thus examined the tillering capacity and structural characteristics of four Brachiaria brizantha cultivars (Xaraés, Piatã, Marandu, and Paiaguás) and one Brachiaria decumbens cultivar (Basilisk) in the Brazilian semi-arid region during the dry season (September to March). The experiment was laid out in a randomized block design with repeated measures over time in which five treatments were tested in four replicates. Tillering parameters, pasture production, and structural variables were evaluated. There was no interaction effect of cultivar × evaluation period on the tiller appearance (p= 0.1774), mortality (p= 0.1952) or survival (p= 0.4469) rates. The highest tiller appearance and mortality rates were observed in Marandu, while the highest survival rates were found in Marandu and Paiaguás. The index of tiller population stability was higher than or equal to 1.0 in all cultivars. Cultivar Basilisk showed the highest herbage mass yield (4448.0 kg DM ha -1 ), whereas Basilisk exhibited the highest yields of leaf (1845.9 kg DM ha -1 ), stem (1676.9 kg DM ha -1 ), and dead material (925.2 kg DM ha -1 ). The highest leaf:stem ratio (1.8) was found in Marandu. Cultivar Xaraés had the highest canopy (70.8 cm). The B. brizantha and B. decumbens cultivars evaluated in this study have the potential for cultivation in areas with marked water deficits, as is the case of the Brazilian semi-arid region. Cultivars Marandu, Basilisk, and Paiaguás exhibited the greatest tillering dynamics as well as the highest herbage-mass yield.

RESUMO.A ovinocultura se faz atuante em praticamente todos os continentes, a ampla difusão da espécie se deve principalmente a seu poder de adaptação. Devido aos fatores geoclimáticos, os países tropicais e subtropicais se destacam e se estabelecem no cenário agropecuário, e o Brasil não se torna exceção nesse mercado. O Brasil por possuir parte considerável do rebanho produzido em pasto, que se constitui em uma das formas econômicas e práticas de produzir e oferecer volumoso aos ruminantes, é um dos principais produtores de carne a um dos menores custos de produção. Os climas tropicais e subtropicais além de favorecer condições ideais para a produção e desenvolvimento dos setores agrícolas e pecuários como, por exemplo, o cultivo de pastagens e a criação de ruminantes, também proporciona condições favoráveis para o desenvolvimento e sobrevivência dos nematoides gastrintestinais, que por sua vez atuam negativamente no desempenho dos animais, em especial, os ovinos. Os nematoides gastrintestinais quando não controlados podem causar prejuízos de 30 a 40% no desempenho animal, principalmente o comprometendo no desenvolvimento de animais jovens e de matrizes em período reprodutivo que são as categorias mais sensíveis, e que estão intimamente ligados ao crescimento do plantel. Os principais nematoides que acometem os pequenos ruminantes e de maior importância econômica para e exploração de ovinos são:Haemonchus contortus e Trichostrongylus axei, ambos localizados no abomaso; Trichostrongylus colubriformis, Strongyloides papillousus, Cooperia sp. e Bunostomum trigonocephalum, no intestino delgado e Oesophagostomum columbianum, Trichuris ovis, T. globulosa e Skrjabinema sp., no intestino grosso. Características morfofisiológicas das plantas forrageiras como a estrutura foliar, hábito de crescimento e produção de massa verde, associados a fatores climáticos, podem ser fatores que influenciam a permanência dos diferentes estágios de vida livre dos nematoides gastrintestinais no ambiente, pastos que não proporcionam incidência de raios solares no estrato inferior das touceiras e solos, propiciam sombreamento e umidade podendo potencializar a reinfecção dos animais. Palavras chave: endoparasitos, Haemonchus contortus, ovinos, pastoGastrointestinal nematodes in sheep of cutting under grazing regime ABSTRACT. Sheep breeding is practiced in practically all the continents, the wide diffusion of the species is due mainly to its power of adaptation. Due to geoclimatic factors, tropical and subtropical countries stand out and settle in the agricultural scenario, and Brazil does not become an exception in this market. Brazil, because it has a considerable part of the herd produced in pasture, which is one of the economic and practical ways of producing and offering bulky ruminants, is one of the main meat producers at one of the lowest production costs. Tropical and subtropical climates, in addition to favoring optimal

The objective of this study was to evaluate the effect of different protein sources on the performance of lamb ewes and their offspring supplemented in deferred pasture. The treatments were the different protein sources: soybean meal, cotton cake, babassu cake and coconut cake. The ewes were weighed and evaluated for their body condition score during the gestation, parturition and weaning phases. The lambs were weighed at birth and at weaning. The structural variables and chemical composition of the pasture were evaluated during the usage period. Grass height and forage mass were higher when the ewes were in the gestation and weaning stages. The leaf mass was not altered during the pasture usage with a mean value of 566.1kg ha-1 DM. The highest levels of crude protein in the leaf blade were observed during the parturition and weaning phases. The body weight of the ewes did not differ between the sources with averages 45.0, 39.9 and 36.6kg for the gestation, parturition and weaning phases, respectively. Weights at birth and at weaning had an effect from protein sources, with the highest values observed in the lambs of ewes who received soybean meal and babassu cake supplementation. The lambs of ewes supplemented with soybean had higher average daily gain and total gain. Babassu, coconut and cotton cakes can replace soybean meal in supplementation of ewes in deferred pasture.