Resumo

O presente estudo foi desenvolvido com o objetivo decaracterizar o potencial produtivo e o valor nutritivo das espécies forrageiras implantadas na fazenda, de outubro de 2018 a março de 2019. As espécies identificadas são Brachiaria Brizantha e gênero Cynodon.O delineamento experimental utilizado foi o de blocos ao acaso com dois tratamentos e três repetições, técnica direta (método de quadrado) que consiste em seis gaiolas metálicas de 0,50 m x 0,50 m fixadas, sendo três por cada parcela. A cada 30 dias realizou-se o corte da massa de forrageira em cada uma das gaiolas a uma altura de 10 cm do solo, e enviadas ao laboratório Central Agroindustrial do Ministério da Agricultura em Luanda para análise bromatológica. Variáveis analisadas: matéria mineral (MM) 10,7% e 7,6%; umidade (U) 24,12% e 32,9%; proteína bruta (PB) 3,93% e 3,19%; fibra bruta (FB) 0,35% e 3,19%; extrato etéreo (EE) 1,14% e 0,98%; cálcio (Ca) 0,39% e 0,33%, fósforo (P) 0,12% e 0,16%; potássio (K) 3,56% e 2,47% de médias respectivamente para as espécies identificadas são Brachiaria Brizantha e gênero Cynodon . Calculou-se o Extrato não nitrogenado, Carboidratos, Energia bruta, produtividade da pastagem e a capacidade de lotação. A produtividade de MS foi considerada relativamente baixa em ambos osgêneros com média de 195,06 kg e 178,08 kg para a Brachiaria Brizantha e gênero Cynodon, respectivamente.Todavia os dados obtidos podem servir como base para a continuidade de estudos, além da sua importância para o estabelecimento de banco de dados sobre produtividade e valor nutritivo das pastagens, haja vista a falta dessas informações em Angola.

The present study was developed with the objective of characterizing the productive potential and nutritional value of forage species implemented on the farm, from October 2018 to March 2019. The species identified are Brachiaria Brizantha and the genus Cynodon.The experimental method used was the direct technique (square method) which consists of six metal cages measuring 0.50 m x 0.50 m fixed, three for each plot. Every 30 days, the forage mass was cut in each of the cages at a height of 10 cm from the ground andsent to the Central Agroindustrial laboratory of the Ministry of Agriculture in Luanda for bromatological analysis. Variables analyzed: mineral matter (MM) 10.7% and 7.6%; humidity (U) 24.12% and 32.9%; crude protein (CP) 3.93% and 3.19%; crude fiber (FB) 0.35% and 3.19%; ether extract (EE) 1.14% and 0.98%; calcium (Ca) 0.39% and 0.33%, phosphorus (P) 0.12% and 0.16%; potassium (K) 3.56% and 2.47% of averages respectively for the identified species are Brachiaria Brizantha and genus Cynodon.The non-nitrogen extract, carbohydrates, gross energy, pasture productivity and stocking capacity were calculated. DM productivity was considered relatively low in both genera with an average of 195.06 kg and 178.08 kg for Brachiaria Brizantha and genus Cynodon,respectively. However, the data obtained can serve as a basis for continuing studies, in addition to its importance for establishing a database on the productivity and nutritional value of pastures, given the lack of this information in Angola.KEYWORDS: production; forage; nutrition.

Resumo

In Brazil, urea is the most used nitrogen (N) fertilizer to improve forage production. However, their excessive use can cause environmental impacts through N losses, such as ammonia (NH3) volatilization. Therefore, the current study adjusted and estimated the NH3 volatilization from urea applied on tropical pastures in three rainfall conditions using mathematical models. Data were collected from Marandu grass (Brachiaria brizantha) fertilized with 50 kg N ha-1 during wet, intermediate, and dry conditions. Ammonia volatilization was measured in five semi-open chambers for 21 days. The linear, quadratic, exponential, Gompertz, Groot, and Richards models were tested for fitting and estimating the NH3 volatilization. The Gompertz, Groot, and Richards models generated predictions similar to the observed data, with a high determination coefficient, indicating a better fit of these equations to data, with precision and accuracy. However, the Groot model was selected due to the lowest root mean square error of prediction (0.29 % total N lost as NH3). The greatest N loss as NH3 volatilization occurred in the wet, followed by intermediate and dry conditions (20.2, 17.0, and 11.3 % total N lost as NH3, respectively). Therefore, nitrogen losses as NH3 volatilization after application of 50 kg N ha-1, as urea source, are altered according to the weather conditions, reaching 20% of N added in the wet rainfall period. The Groot model is recommended for fitting and estimating the NH3 volatilization from urea applied on Marandu grass pastures in the wet and dry rainfall conditions.

No Brasil, a ureia é o fertilizante nitrogenado mais utilizado para melhorar a produção de forragem. No entanto, seu uso excessivo pode causar impactos ambientais por meio de perdas de nitrogênio (N), como a volatilização da amônia (NH3). Portanto, o objetivo do presente estudo foi ajustar a volatilização de NH3 da ureia aplicada em pastos tropicais em três condições de chuva utilizando modelos matemáticos. Dados foram coletados de pastos de capim-marandu (Brachiaria brizantha) adubado com 50 kg N ha-1 em condições úmidas, intermediárias e secas. A volatilização da NH3 foi medida em cinco câmaras semiabertas durante 21 dias. Os modelos, linear, quadrático, exponencial, Gompertz, Groot e Richards foram testados para ajuste e estimativa da volatilização do NH3. Os modelos de Gompertz, Groot e Richards geraram predições semelhantes aos dados observados, com alto coeficiente de determinação, indicando um melhor ajuste dessas equações aos dados, com acurácia e precisão. No entanto, o modelo Groot foi selecionado devido ao menor erro quadrático médio das predições (0,29% de N total perdido como NH3). A maior volatilização de NH3 ocorreu em condições climáticas úmida, seguido por intermediária e seca (20,2; 17,0 e 11,3% de N total perdido como NH3, respectivamente). Portanto, as perdas de N como volatilização de NH3 após a aplicação de 50 kg N ha-1, como fonte de ureia, são alteradas de acordo com as condições climáticas, atingindo a 20% do N adicionado nas condições úmidas. O modelo Groot é recomendado para ajuste e estimativa da volatilização de NH3 da ureia aplicada em pastos de capim Marandu em condições úmidas e secas.

Resumo

The objective of this study was to evaluate the fermentation profile and nutritional value of Marandu grass silage (Urochloa brizantha(Hoschst.Ex. A. Rich) R. D. Webster cv. Marandu Syn. Brachiaria brizantha(Hochst. Ex A. Rich) Stapf cv. Marandu} with different levels of inclusion of dehydrated banana peel. The experiment was conducted in a completely randomized design with marandu grass with five levels of dehydrated banana peel (0, 10, 20, 30 and 40% of natural matter) with eight replicates. The data collected were submitted to analysis of variance and, when the "F" test was significant, the inclusion levels of the pre-dried banana peel were analyzed utilizing orthogonal polynomials and linear and quadratic regression models. The mean values of N-NH3 were adjusted to the linear regression model (p<0.01), while the pH values had the lowest value of 4.3 with the inclusion of 15% of banana peel. The mean values of the gas loss (PG, P = 0.01) and the dry matter recovery (RMS; P = 0.01) were adjusted to the quadratic regression model, with a minimum point of 16.15% for losses and 21% as the maximum point for dry matter recovery. The rate of degradation potential degradability of the dry matter (SD; P = 0.74) did not vary with the inclusion of the banana peel. The potential degradability standardized at 2, 5 and 8% was adjusted to the regressive linear regression model (p<0.01), and for each percentage point of inclusion of the banana peel, there was a reduction of 0.23, 0.14 and 0.10%, respectively. The inclusion of 10 to 20% dehydrated banana peel in the marandu grass silage improves the fermentation profile and the nutritional value of the silage.(AU)

Resumo

Supplementation strategies have been studied to increase animal performance and the quality of meat. Thus, this study was carried out to evaluate the influence of different supplementation strategies on the performance, feed intake, digestibility and ingestive behaviour of crossbred steers on Brachiaria brizantha pasture, during the dry season. The experiment was performed in Bahia, Brazil, from August 2015 to January 2016, with a dry season of 203 days. Thirty-three crossbred steers with an average weight of 269.5 ± 41.8 kg were distributed in a completely randomised design with three treatments and 11 replicates per treatment. The results were analysed using an ANOVA and a Tukey test, with a 5% probability of error. The treatments were mineral salt with urea and the supplementation of protein based on the animals' body weight (BW), as follows: 0.1 and 0.2% BW. There was no effect of supplementation strategy on the initial and final body weights. Supplementation strategies did not influence (p > 0.05) the variables related to the intake of total dry matter. There was an effect (p < 0.05) on the dry matter and crude protein digestibility coefficients. For ingestive behaviour, feed intake, grazing time and idle time tended to be altered by the supply strategies (p < 0.05), but rumination was not affected (p > 0.05) by the evaluated strategies. In conclusion, the supplementation strategies used during the dry season resulted in a similar performance; therefore, the adopted strategy can be chosen according to the economic and regional conditions of the production system. Thus, the strategy adopted could be chosen according to the economic and regional conditions of the production.(AU)

Resumo

The aim of this study was to identify differences in morphogenesis, structure, and forage accumulation rate of Urochloa brizantha cv. MG13 Braúna, from Urochloa cv. Cayana and Urochloa cv. Convert 330 (sabiá grass) during the deferment period. The experimental design was completely randomized, with four replications in experimental plots of 12.25m2. The evaluations took place for two years, 2021 and 2022. The deferment period was 90 days. Phyllochron (PHY) and leaf senescence rate (LSR) were lower at the beginning of deferred, contrary to leaf elongation rate (LER) and population density tillers (PDT). Stem growth rate (SGR) was higher in 2021 and at the beginning of deferment. Leaf growth rate (LGR) and total growth rate (TGR) were higher at the beginning of deferment. The braúna grass presented higher PDT. The SGR and the TGR of cayana grass are superior to those of braúna grass. The braúna grass produces a canopy consisting of lighter and denser byts, compared to other weeds. In Uberlândia, MG, braúna grass with an initial height of 30cm produces less stem, while cayana grass produces more forage during deferral.

O objetivo deste estudo foi identificar diferenças nos padrões de morfogênese, de estrutura e de taxa de acúmulo de forragem da Urochloa brizantha cv. MG13 Braúna, da Urochloa cv. Cayana e da Urochloa cv. Convert 330 (capim-sabiá), durante o período de diferimento. O delineamento experimental foi inteiramente ao acaso, com quatro repetições, em parcelas experimentais de 12,25m2. As avaliações ocorreram por dois anos, 2021 e 2022. O período de diferimento foi de 90 dias. O filocrono (FIL) e a taxa de senescência foliar (TSF) foram menores no início do diferimento, contrariamente à taxa de alongamento foliar (TAlF) e à densidade populacional de perfilhos (DPP). A taxa de crescimento de colmo (TCC) foi maior em 2021 e no início do diferimento. As taxas de crescimento de folha (TCF) e a taxa de crescimento total (TCT) foram maiores no início do diferimento. O capim-braúna apresentou maior DPP. A TCC e a TCT do capim-cayana são superiores às do capim-braúna. O capim-braúna produz um dossel constituído por perfilhos mais leves e mais densos, em comparação aos demais capins. Em Uberlândia, MG, o capim-braúna com altura inicial de 30cm produz menos colmo, enquanto o capim-cayana produz mais forragem durante o diferimento.

Resumo

The present study evaluated germination, production, and morphological composition of Urochloabrizantha intercropped with corn and sorghum; and silage fermentation losses and aerobic stability of intercrop silage using microbial inoculant. Twenty experimental parcels (5.0 × 3.6 m) were used in a blocked randomized design to evaluate four treatments obtained from a 2 × 2 factorial arrangements: I) crop material (corn vs. sorghum) and II) Brachiaria (U. brizantha) establishment (present vs. absent). Corn- and sorghum-brachiaria integrated systems showed similar brachiaria germination, forage yield, and morphological composition. There was no crop and brachiaria interaction effect on the variables related to corn and sorghum plants and the total productivity. Brachiaria decreased the stem diameter and increased the population of maize and sorghum plants. However, it did not affect systems productivity. Microbial inoculation did not affect corn silage effluent losses and reduced sorghum silage effluent losses. In corn silage, brachiaria did not affect gas losses, while in sorghum silage, brachiaria increased the gas losses. Total losses were higher in sorghum silage than in corn silage, which resulted in a lower DM recovery. The treatments did not affect the pH of the silage after aerobic exposure. However, brachiaria increased silage temperature evaluated at 32 and 40 hours after aerobic exposure. Thus, corn or sorghum consortium has similar brachiaria morphological composition and productivity. Moreover, in intercropped silage, brachiaria increases effluent losses and reduces silage aerobic stability.

O presente estudo tem por objetivo avaliar a germinação, produção e composição morfológica de Urochloabrizantha consorciada com milho e sorgo, perdas de fermentação da silagem e estabilidade aeróbia da silagem consorciada com inoculante microbiano. Vinte parcelas experimentais (5.0 × 3.6 m) foram usadas em um delineamento em blocos casualizados para avaliar quatro tratamentos em arranjo fatorial 2 x 2: I) Cultura (milho vs. sorgo) e II) Estabelecimento da Brachiaria (U. brizantha) (presente vs. ausente). Os sistemas integrados milho e sorgo-brachiaria apresentaram germinação, produção de forragem e composição morfológica semelhante. Não houve efeito da interação cultura e braquiária sobre as variáveis relacionadas às plantas de milho e sorgo e a produtividade total. A brachiaria diminuiu o diâmetro do caule e aumentou a população de plantas de milho e sorgo. No entanto, não afetou a produtividade dos sistemas. A inoculação microbiana não afetou as perdas de efluente da silagem de milho e reduziu as perdas de efluente da silagem de sorgo. Na silagem de milho, a brachiaria não afetou as perdas de gás, enquanto na silagem de sorgo, a brachiaria aumentou as perdas de gás. As perdas totais foram maiores na silagem de sorgo do que na silagem de milho, o que resultou em menor recuperação da MS. Os tratamentos não afetaram o pH da silagem pós exposição aeróbia. Contudo, a brachiaria aumentou a temperatura da silagem 32 e 40 horas após exposição aeróbia. Portanto, os consórcios milho e sorgo-brachiaria apresentam composição morfológica e produtividade semelhantes. Além disso, na silagem consorciada, a brachiaria aumenta as perdas por efluentes e reduz a estabilidade aeróbia.

Resumo

The objective was to investigate the feeding behavior of sheep in marandu grass (Brachiaria brizantha cv. Marandu) pastures under continuous stocking with the same average height and different horizontal structures. The treatments were composed of less heterogeneous pastures (P-H, 24% coefficient of variation of plant heights and more heterogeneous pastures (P+H, 46% coefficient of variation of plant heights) and the locations of the picket, front and back, were also evaluated. A randomized block design was used, with split plots in space and four replications in two years. Crossbred lambs were used, managed under continuous stocking and variable stocking rate, to maintain average height of pastures at 30 cm. Greater masses of total forage, live leaf, live stem and dead material, and greater time of sheep in rumination, occurred in the front, in relation to the paddock background. In P-H, grazing time (GT) did not vary between regions. In P+H, GT was lower at the front than at the background. Idle time (IT) was similar between P-H and P+H. However, the animals remained more IT in the front than in the background. The feeding behavior of grazing sheep is modified in marandu grass pastures under continuous stocking with the same average height, but with different spatial variability of the vegetation.

Objetivou-se investigar o comportamento ingestivo de ovinos em pastos de capim-marandu (Brachiaria brizantha cv. Marandu) sob lotação contínua com mesma altura média e diferentes estruturas horizontais. Os tratamentos foram compostos de pastos menos heterogêneo (P-H, 24% de coeficiente de variação das alturas das plantas) e pastos mais heterogêneo (P+H, 46% de coeficiente de variação das alturas das plantas), também foi avaliado os locais do piquete, frente e fundo. O delineamento utilizado foi de blocos ao acaso, com parcelas subdivididas no espaço e quatro repetições em dois anos. Foram utilizadas borregas mestiças, manejadas sob lotação continua e com taxa de lotação variável, para manter altura média dos pastos em 30cm. Maiores massas de forragem total, folha viva, colmo vivo e material morto, e maior tempo dos ovinos em ruminação, ocorreram na frente, em relação ao fundo do piquete. No P-H, o tempo em pastejo (TP) não variou entre as regiões. No P+H, o TP foi menor na frente do que no fundo. O tempo em ócio (TO) foi semelhante entre os P-H e P+H. Porém, os animais permaneceram mais TO na frente que no fundo. O comportamento ingestivo de ovinos em pastejo é modificado em pastos de capim-marandu sob lotação contínua com mesma altura média, porém com diferentes variabilidades espaciais da vegetação.

Resumo

The objective of this study was to evaluate the potential of improving the economic value of integrated crop-livestock systems (ICLS) compared to conventional systems specialized in monoculture. The experimental area was 16.02 ha, divided into 18 paddocks of 0.89 ha each, organized in a randomized block design, with three replicates and six models of production systems: crop system [corn ( Zea mays ) grain production], livestock system (beef cattle under grazing conditions), and four ICLS, identified as: ICLS-1, corn integrated with Marandu palisadegrass [ Urochloa brizantha (Hoechst. ex A. Rich.) R.D. Webster cv. Marandu (syn. Brachiaria brizantha cv. Marandu] sown simultaneously without herbicide; ICLS-2, corn and Marandu palisadegrass sown simultaneously with herbicide; ICLS-3, corn and Marandu palisadegrass with lagged sowing; and ICLS-4, corn and Marandu palisadegrass sown simultaneously, with herbicide in rows and between-rows of corn. We demonstrated the economic impact analysis combined with the risk optimization and discounted cash flow techniques based on Monte Carlo simulation, considering price and productivity uncertainties. The indicators of added value and return on investment of ICLS had an economic advantage compared with conventional systems. It was also found that ICLS needed a smaller operational area than conventional systems for the economic break-even point. Integrated systems provide lower financial and operational risk levels and greater economic value per hectare compared with conventional systems specialized in monoculture.(AU)

Resumo

This study aimed to evaluate phosphorus (P) concentration in serum and bone, the percentage of ash and the specific bone density of buffaloes on Ilha de Marajó before and after mineral supplementation. For this study, 14 crossbred buffaloes of Murrah and Mediterranean descent aged between 18 and 36 months were used. The average values of P before supplementation in serum and bone, the percentage of bone ash and the specific bone density were 5.68mg/dL±1.18, 16.53%±0.53, 59.95%±1.96 and 1.52g/cm3±0.32, respectively, which demonstrated P deficiency in animals raised on Ilha de Marajó. After supplementation with P for a period of seven months, the values were 6.61mg/dL±0.87, 16.90%±0.56 and 60.30%±0.95 and 1.71g/cm3±0.21, respectively. These results showed a significant increase in P concentration in blood serum, specific bone density and percentage of P in ash (P<0.05), but there was no significant increase in the percentage of ash. The average increase in P in the serum and ash did not reach normal levels in all animals; however, 28.6% of the animals had normal values of P in serum and 50% in the ash, and 64.3% had normal specific bone density values. The nonre-establishment, in some of the animals, of the variables of P serum and bone after supplementation for seven months may have occurred as a result of the low intake of the mineral mixture and by the low concentration of P in the Brachiaria brizantha cv. Marandu used for feeding animals during the experiment.

Objetivou-se avaliar as concentrações de fósforo (P) no soro e no osso, o percentual de cinzas e a densidade óssea específica em búfalas da Ilha de Marajó antes e após suplementação mineral seletiva. Foram utilizadas 14 búfalas mestiças de Murrah com Mediterrânea, com idades entre 18 e 36 meses. Os valores médios de P, antes da suplementação, no soro, no osso, o percentual de cinzas e a densidade óssea específica foram de 5,68mg/dL±1,18, 16,53%±0,53, 59,95%±1,96 e 1,52g/cm3±0,32, respectivamente, o que demonstra deficiência de P nos animais criados na Ilha de Marajó. Após a suplementação com P por um período de sete meses os valores foram 6,61mg/dl±0,87, 16,90%±0,56 e 60,30%±0,95 e 1,71g/cm3±0,21 respectivamente. Esses resultados caracterizam um aumento significativo nas concentrações de P no soro sanguíneo, na densidade óssea específica e no percentual de P nas cinzas (P<0,05), porém não houve um aumento significativo no percentual de cinzas. O aumento médio nos valores de P no soro e nas cinzas não alcançou patamares de normalidade em todas as búfalas, entretanto 28,6% delas tinham valores normais de P no soro e 50% nas cinzas, 64,3% tinham valores normais da densidade óssea específica. O não restabelecimento, em parte dos animais, das variáveis ósseas e sanguíneas após suplementação com P durante sete meses pode ter ocorrido em virtude da baixa ingestão da mistura mineral e da baixa concentração de P em Brachiaria brizantha cv. Marandu utilizada para alimentação dos animais durante o experimento.

Resumo

Phosphorus (P) is one of the main nutrients capable of increasing yields of tropical grasses. The definition of adequate P fertilizer rates can contribute to improving forage production of pastures. However, the efficiency in the response of different genotypes of Urochloa mosambicensis (Hack.) Dandy (Bushveld herringbone grass) to P fertilizer rates is not known. This study aimed to quantify the response of U. mosambicensis genotypes to P fertilizer levels and classify the genotypes as to efficiency and responsiveness. The experiment was carried out in pots, under controlled conditions, in a completely randomized design, in a 2 x 9 factorial with five replications. The factors consisted of equivalent P rates of 10 and 90 kg ha-1 of P2O5 (triple superphosphate) and eight genotypes of U. mosambicensis (UmCO-1 (2), UmCO-2 (2), UmCO-4 (1), UmCO-8 (1), UmCO-11 (2), UmCO-12 (2), UmCO-13 (2) and UmCO-14 (2)), in addition to a control, Urochloa brizantha syn. Brachiaria brizantha cv. BRS Piatã. Each experimental unit consisted of one pot. Biometric attributes and dry mass yield were evaluated over four cutting cycles. There was no effect of the P fertilization x genotypes interaction for the variables evaluated. However, the highest fertilizer rate increased dry mass yield and tiller population density in all genotypes and cuttings evaluated. The genotype UmCO-4 (1) and the cultivar BRS Piatã proved to be responsive to and efficient in P use. The highest P rate promoted greatest production of dry mass and greatest number of tillers in all genotypes of U. mosambicensis.(AU)

O fósforo (P) é um dos principais nutrientes capazes de aumentar a produtividade de gramíneas tropicais. A definição de doses de P pode contribuir para aumentar a produção de forragem em pastagens cultivadas. Todavia não se conhece a eficiência na resposta de diferentes genótipos de capim-corrente (Urochloa mosambicensis (Hack.) Dandy) a doses de P. Este estudo objetivou quantificar a resposta de genótipos de capim-corrente a níveis de adubação com P e classificá-los segundo a sua eficiência e responsividade. O experimento foi conduzido em vasos, em condições controladas, no delineamento inteiramente casualizado, num esquema fatorial 2 x 9, com cinco repetições. Os fatores consistiram de doses equivalentes de P de 10 e 90 kg ha-1 de P2O5 (superfosfato triplo) e oito genótipos de U. mosambicensis (UmCO1 (2), UmCO-2 (2), UmCO-4 (1), UmCO-8 (1), UmCO-11 (2), UmCO-12 (2), UmCO-13 (2) e UmCO-14 (2)), além da testemunha Urochloa brizantha syn. Brachiaria brizantha cv. BRS Piatã. Cada unidade experimental foi constituída de um vaso. Foram avaliados atributos biométricos e rendimento de massa seca ao longo de quatro ciclos de corte. Não houve efeito da interação entre adubação x genótipos para as variáveis avaliadas. Entretanto, a maior dose do fertilizante incrementou o rendimento de massa seca e densidade populacional de perfilhos em todos os genótipos e cortes avaliados. O genótipo UmCO-4 (1) e a cultivar BRS Piatã revelaram-se responsivos e eficientes no uso de P. A maior dose de P promoveu maior produção de massa seca e maior número de perfilhos em todos os genótipos de U. mosambicensis.(AU)

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The objective was to examine the effect of two short-term protein-energy supplementation (STPES) strategies at the rearing phase on the performance of Nellore calves grazing on Mombaça or Marandu grasses. The experiment used 72 calves (7-mo old, 229±3.0 kg body weight [BW]) allotted in a completely randomized block design to four treatments in a 2 × 2 factorial arrangement: two forage cultivars (Panicum maximum cv. Mombaça vs. Brachiaria brizantha cv. Marandu) and two STPES (WEAN ­ STPES immediately after weaning vs. TRAN ­ STPES in the transition of dry-rainy). The WEAN animals received 1 kg day−1 (n = 36) of a protein-energy supplement, whereas TRAN animals were subjected to STPES at 2 g/kg BW day−1 (n = 36), both for 53 days. Every 28 days, calves were weighed to measure performance, and pastures were sampled to evaluate productive and structural traits. Growth performance was analyzed considering a completely randomized block design with a 2 × 2 arrangement of treatment, whereas forage responses included repeated measures. Marandu had a higher forage mass (3,586 kg) than Mombaça (2,890 kg), but there was no difference in forage mass in each cultivar between preconditioning periods. The nutritional composition of Marandu and Mombaça cultivars did not differ and had similar results of in vitro fermentation variables. Stocking rate was higher for WEAN, in the Mombaça pastures. The STPES at weaning on Marandu provided greater gains per area. When applied in the period following the weaning and coinciding with the dry season, the STPES improves the performance of newly weaned calves kept on Marandu and Mombaça grasses.(AU)

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Background: The peroneus tertius muscle is responsible for tarsal flexion and coordinate extension of the stifle joint. The most common causes of rupture are excessive effort when trying to rise on a slippery surface, mounting, or being mounted. Rupture of the peroneus tertius muscle is characterized by an inability to flex the hock. Most cases are not curable, presenting an unfavorable to poor prognosis, and the animal has to be euthanized. This study aimed to report the clinical picture and treatment of a bilateral rupture of the peroneus tertius muscle in a cow from the municipality of Castanhal, state of Pará (Amazonian biome). Case: We report the clinical picture and treatment of a bilateral rupture of the peroneus tertius muscle in a 4-year-old cow, mixed breed, weighing approximately 400 kg, calved 3 months ago, belonging to a batch of 40 cattle kept on extensive breeding system in a pasture of Urochloa (Brachiaria) brizantha. The clinical signs appeared after the cow was mounted by a 1,100 kg bull and consisted of lameness, falling into sternal decubitus with hind limbs extended backward, hyperextension of the hocks with flexed stifle, with the tibia and metatarsus in a straight line, which lead to a 90-degree position of the femur and knee. Abrasions in the dorsal region of the fetlocks reinforce evidence of dragging hooves. Diagnosis of bilateral rupture of the peroneus tertius muscle was performed by a clinical examination and semiological test. Nonsteroidal anti-inflammatory drugs (flunixin meglumine, 2,2 mg/kg, every 24 h for 4 days) were prescribed for treatment, in addition to resting in a paddock with good availability of pasture, water, and mineral salt. After 3 months, we observed an improvement of the clinical signs, and after 6 months, an almost complete recovery. Only a slight difficulty in flexing the hock when moving remained. Discussion: In the present report, bull mounting was the probable cause of the hyperextension of both hocks and the bilateral rupture of the peroneus tertius muscle. According to the handler, these clinical signs were only evidenced after the animal was mounted. As stated in the literature, accidents such as falls, slips, mounting or being mounted, as well as excessive traction and over-elevation of the limb are considered predisposing factors for the onset of the disease. Rupture of the peroneus tertius muscle is unusual in production animals; therefore, the low occurrence of reports on this kind of rupture in the literature makes this case even more unique. The bilateral injury differs from cases described in the literature, in which the reported injuries were always unilateral. Our findings reinforce the hypothesis that the act of mounting was the triggering factor for the bilateral rupture of the animal peroneus tertius muscle. The breeding system also differs from the cases diagnosed by the same authors, since they describe the disease in bovines kept on intensive or semi-intensive breeding. In the present case, the cattle were kept on an extensive breeding system. The extension and flexion tests used in the clinical examination allowed for the diagnosis of rupture of the peroneus tertius muscle in both limbs, similarly to what has been reported by other authors. Anamnesis, clinical findings, and exclusion of different diagnoses were decisive for establishing the diagnosis. The treatment chosen was efficient, even though the case was severe, as the injury occurred in both hind limbs.

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The objective of this work was to evaluate the productivity and extraction of macronutrients by Urochloa brizantha cv. BRS Paiaguás (Syn. Brachiaria brizantha cv. BRS Paiaguás) single and intercropped with pigeon pea (Cajanus cajan cv. BRS Mandarim), subjected to four doses of nitrogen applied in topdressing (0, 80, 160 and 240 kg ha¨¹). The experiment was carried out in São Luís de Montes Belos, GO, in soil classified as dystrophic red latosol, under Cerrado conditions. Plant height and dry mass of pigeon pea, plant height, number of tillers, dry mass, and macronutrient extraction by Paiaguás palisadegrass were evaluated. Higher mass production was observed in the pasture intercropped with the legume, requiring a lower amount of N. Based on the results exposed, the cultivation of Paiaguás palisadegrass reaches higher productivity when intercropped with a legume such as pigeon pea, in addition to providing greater efficiency in the use of nutrients such as N, P and K. Nitrogen fertilization has a negative influence on the production of dry mass and height of pigeon pea plants.

Objetivou-se, com o trabalho, avaliar a produtividade e a extração de macronutrientes pelo capim-solteiro e consorciado com feijão-guandu, submetidos a quatro doses de nitrogênio aplicadas em cobertura (0, 80, 160 e 240kg ha). O experimento foi conduzido em São Luís de Montes Belos, GO, em solo classificado como Latossolo Vermelho Distrófico, sob condições de Cerrado. Foram avaliados a altura de plantas e massa seca do guandu, a altura de plantas, os números de perfilhos, a massa seca e a extração de macronutrientes pelo capim-paiaguás. Foi observada maior produção de massa na pastagem consorciada com a leguminosa, demandando menor quantidade de N. Com base nos resultados expostos, o cultivo de capim-paiaguás atinge maiores produtividades quando consorciado com uma leguminosa, como o feijão-guandu, além de proporcionar maior eficiência no uso de nutrientes, como N, Pe K. A adubação nitrogenada tem influência negativa sobre a produção de massa seca e a altura das plantas de feijão-guandu.

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This study examined the effects of annual nitrogen (N) rates of 100 and 200 kg ha-¹ on the morphogenetic and structural traits of Ipyporã grass (Brachiaria brizantha × Brachiaria ruziziensis) under intermittent grazing during the seasons of the year. The experiment was laid out in a randomized-block design with two treatments and three area replicates. Ipyporã grass pastures were grazed by beef cattle. Morphogenetic and structural traits of the forage canopy were evaluated using the marked-tiller technique. Forage accumulation and tiller density (TD) were also evaluated. Significant interaction effects (P < 0.05) between N rates and seasons were observed for the rest period, leaf lifespan (LLS), phyllochron, stem elongation rate (SER) and final leaf length (FLL). During winter, the rest period was shorter (40 vs. 50 days) in the pastures fertilized with 200 kg ha-¹ N. Conversely, in winter, the pastures fertilized with 100 kg ha-¹ N showed higher LLS, SER and phyllochron values, but lower FLL values. There was no isolated effect of N rates (P > 0.05) on forage accumulation rate; leaf appearance, elongation or senescence rates; leaf:stem ratio; or TD. However, the effect of seasons was significant for these variables, with the highest values occurring during spring and summer. The use of 200 kg ha-¹ N in Ipyporã grass pastures reduces the seasonality of forage production.

O objetivo foi avaliar os efeitos das doses anuais de 100 e 200 kg ha-¹ de nitrogênio (N) sobre as características morfogênicas e estruturais do capim-ipyporã, em lotação intermitente durante as estações do ano. O delineamento experimental foi em blocos ao acaso, com dois tratamentos e três repetições de área. Os pastos de capim-ipyporã foram submetidos ao pastejo por bovinos de corte. Foram avaliadas as características morfogênicas e estruturais do dossel forrageiro por meio da técnica de perfilhos marcados. Também foi avaliado o acúmulo de forragem e a densidade populacional de perfilhos (DPP). Foi observada interação significativa (P < 0,05) das doses de N e estações do ano para o período de descanso (PD), duração de vida das folhas (DVF), filocrono, taxa de alongamento de colmos (TAlC) e comprimento final das folhas (CFF). Durante o inverno, o PD foi menor (40 vs 50 dias) nos pastos adubados com 200 kg ha-¹ de N. Em contra partida, no inverno, os pastos adubados com 100 kg ha-¹ de N apresentaram maiores valores para DVF, filocrono e TAlC, e menores para o CFF. Não foi observado efeito isolado de doses de N (P > 0,05) para as taxas de acúmulo de forragem; de aparecimento, alongamento e de senescência de folhas, relação folha:colmo e para a DPP. No entanto, o efeito das estações foi significativo para estas variáveis, com os maiores valores observados durante a primavera e verão. O uso de 200 kg ha-¹ de N para pastos de capim-ipyporã promove redução da estacionalidade de produção da forrageira.

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The aim of the present study was to evaluate the effects of sowing depth and inoculation with Pseudomonas fluorescens on germination, emergence, shoot and root growth of Urochloa brizantha. A completely randomized design was used, in a 6 × 2 factorial arrangement, with 12 repetitions. The following sowing depths (SD) were evaluated: 0, 1, 2, 3, 6 and 12 cm; and the seed inoculation with P. fluorescens (I): with and without. Evaluations were carried out 25 days after plant emergence. No effects of the PS × I or I interaction were observed for all variables evaluated (P> 0.05). The germination and emergence percentages decreased linearly (P <0.05) as the SD increased. No plant emergence was observed at and at 12 cm depth. The morphometric characteristics of the plants (height, number of leaves, length of root and leaf blade width) decreased linearly with the increase of SD (P <0.05). Dry matter production of the aerial part and root were not affected by SD (P> 0.05). However, an effect was observed on the shoot:root ratio, where plants sown more superficially had a greater relationship. The inoculation with Pseudomonas fluorescens in the seed, has no effect on the initial growth of Marandu grass. On the other hand, greater sowing depths affects negatively the initial growth.(AU)

Objetivou-se avaliar os efeitos de profundidades de semeadura e da inoculação com Pseudomonas fluorescens sobre a germinação, emergência, crescimento aéreo e radicular da Urochloa brizantha. O delineamento foi inteiramente casualizado, em arranjo fatorial 6 × 2, com 12 repetições. Foram avaliadas a profundidade de semeadura (PS): 0, 1, 2, 3, 6 e 12 cm; e a inoculação da semente com P. fluorescens (I): sem e com. As avaliações foram realizadas 25 dias após a emergência das plântulas. Não foram observados efeitos da interação PS × I nem de I para todas as variáveis avaliadas(P> 0.05). Os percentuais de germinação e emergência diminuíram linearmente (P< 0.05) em função do aumento da PS, sendo que na profundidade de 12 cm, não foi observada emergência de plantas. As características morfométricas das plantas (altura, número de folhas, comprimento de raiz e largura de lâmina foliar) diminuíram linearmente em função do aumento da PS (P< 0.05). As produções de massa seca de parte aérea e de raiz não foram afetadas pela PS (P> 0.05), porém, foi observada diminuição da relação parte aérea:raiz com o aumento da OS (P< 0.05). A inoculação com Pseudomonas fluorescens na semente não apresenta efeitos sobe o crescimento inicial do capim Marandú. Por outro lado, profundidades de semeadura maiores afetam negativamente o crescimento inicial.(AU)

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In tropical grass seed production fields, reducing plant size can increase the solar radiation to the base of the plant canopy and improve the quantity and quality of the seeds produced. This research studied the responses of the production components, the productivity, and the seed quality of U. brizantha cv. MG-5 to different canopy sequential cuttings under cultivation conditions in rain fed systems. Two experiments were carried out (agricultural year 2015/16 (s1) and 2016/17 (s2)) in a randomized block experimental design with four repetitions. The treatments consisted of sequential cut-off, indicating the month of the last cut and the agricultural year: for the 2015/16 agricultural year: Aug - s1, Sep - s1, Oct - s1, Nov - s1, Dec - s1, Jan - s1, and Feb - s1; for the 2016/17 agricultural year: Aug - s2; Set - s2; Nov - s2; Dec - s2; Jan - s2, and Feb - s2. Plant growth biometrics, seed quality variables, and productivity were evaluated. The sequential cut strategy increased the productivity and quality of pure seeds when the final cuts were done between November and December. Cuts performed after December increased the reproductive components. However, in the region in question, rainfall levels compromised seed filling; and therefore productivity and quality since the flowering of these cuttings (January and February) occurs in May.

Em campos de produção de sementes de forrageiras tropicais, a redução do porte das plantas pode ser uma estratégia de melhorar os índices de radiação solar no dossel inferior da lavoura, com possíveis consequências positivas para a produtividade e qualidade das sementes produzidas. Neste contexto, foi desenvolvido um trabalho com propósito de estudar as respostas dos componentes de produção, produtividade e qualidade de sementes de U. brizantha cv. MG-5 em razão de cortes sequenciais da parte aérea, em condições de cultivo em sistema de sequeiro. Para tanto foram implantados dois experimentos (ano agrícola 2015/16 - s1 e ano agrícola 2016/17 - s2), em que se adotou o delineamento experimental em blocos casualizados, com quatro repetições. Os tratamentos foram constituídos por cortes sequenciais da parte aérea, sendo que os cortes mensais e a nomenclatura dos respectivos tratamentos indicam o mês do último corte e ano agrícola: Ago - s1; Set - s1; Out - s1; Nov - s1; Dez - s1; Jan - s1 e Fev - s1 para o ano agrícola 2015/16 (s1) e Ago - s2; Set - s2; Nov - s2; Dez - s2; Jan - s2 e, Fev - s2 para o ano agrícola 2016/17 (s2). Foram avaliadas variáveis biométricas de crescimento da planta, e variáveis de qualidade e produtividade de sementes. O manejo de cortes sequenciais incrementa a produtividade e qualidade de sementes puras para cortes finais realizados entre novembro e dezembro. Cortes realizados posteriormente a dezembro aumentam os componentes reprodutivos, entretanto, na região em questão, os índices pluviométricos comprometem o enchimento das sementes e consequentemente a produtividade e qualidade, visto que o florescimento destas épocas de cortes (janeiro e fevereiro) ocorrem em maio.

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Ergot is a fungal disease and causes reductions in seed productivity and quality. We aimed to identify promising genotypes of brachiaria evaluating: (1) seed production potential (number of tillers, racemes per inflorescence, spikelets per raceme, raceme length, weight and number of seeds, and germination) and (2) resistance of seeds to Ergot (infected tillers, infected seeds). Five genotypes of Brachiaria grasses, four non-natural hybrids named BH1619, BH1810, BH1516 and Mavuno Palisadegrass (Urochloa brizantha x Urochloa ruziziensis), and Marandu Palisadegrass (U. brizantha Hoechst cv. Marandu) were evaluated. The BH1619 hybrid, despite the high weight of seeds, produced less viable, pure seeds. The hybrid BH1516 had a lower percentage of flowered tillers (42%) and seeds infected with ergot (8%). Marandu Palisadegrass had a higher percentage of infected tillers (95%) and infected seeds (38%). The hybrid BH1516 was the most resistant to ergot, followed by Mavuno Palisadegras sand BH1619. Among all materials, Mavuno Palisadegrass and BH1516 have a higher potential for seed production due to the higher percentage of flowered tillers and production of pure seeds with high germination capacity. The BH1516 hybrid was resistant to ergot, making it a better choice for use in infected areas used for seed or forage production.(AU)

Resumo

Short-term grazing behavior variables are sensitive to the canopy structure and have an impact on daily forage intake. This study evaluated the effect of pre- and post-grazing canopy heights on the forage harvesting process at a patch scale in a mixture of Brachiaria brizantha (Hochst. ex A. Rich.) Stapf. syn. Urochloa brizantha R.D. Webster cv. Marandu (palisade grass) and Arachis pintoi Krapov. & W.C. Greg. cv. Belomonte (forage peanut). Treatments were allocated to a split-plot arrangement in a completely randomized design. The plots, in their entirety, consisted of two pre-grazing canopy heights: 25 cm (CH25) and 35 cm (CH35); subplots consisted of three levels of defoliation severity: no defoliation (DS0); 20% depletion of pre-grazing canopy height (DS20); and 40% depletion of pre-grazing canopy height (DS40), with eight replications. Heifers were allowed to graze the patches (0.7 × 0.7 m) and their grazing behavior was recorded. Canopy structure measurements were taken both before and after grazing. Patches from CH35 presented greater stem mass for grass (p = 0.001) and legume (p = 0.002) than did patches from CH25. Bite rate, bite mass and instantaneous intake rate were greater for CH25 than for CH35 (p < 0.001, p = 0.068, and p = 0.074), and bite mass and instantaneous intake rate were lower for DS20 compared to DS0 (p = 0.032 and p = 0.016). Greater stem mass in the grazing strata negatively influenced the instantaneous intake rate.

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This study examined the effect of different supplementation strategies for ewes in the last third of gestation, kept on a deferred Brachiaria brizantha cv. Marandu pasture, on their performance and the growth curve of their lambs. A total of 54 ewes, of no defined breed, with an average weight of 41.10±3.10 kg, were used in a completely randomized design, divided into three groups (18 ewes per treatment). In total, 61 lambs were born, 28 females and 33 males, with 3.70±0.55 and 3.68±0.69 kg birth weight, respectively. Treatments were as follows: multiple mixture ad libitum, concentrate supplement at 0.4% live weight (LW), and concentrate supplement at 0.8% LW. Average daily weight gain (ADG, g/animal/day) and total weight gain (TWG, kg/animal) were evaluated in ewes and lambs. Reproductive efficiency indices were measured in the ewes and biometric variables in the lambs. The ADG and TWG of ewes in the last third of gestation were higher in animals supplemented at 0.8% LW. Reproductive efficiency results were superior in ewes supplemented at 0.4% LW. The effect of ewe supplementation on lamb growth curve as estimated by the Gompertz model did not reveal differences between the curves of lambs born to ewes that received supplementation at 0.4 and 0.8% LW. However, supplementing ewes with a multiple mixture induced a reduction in the growth curve parameters of their lambs. The use of concentrated supplementation, at levels of 0.4 and 0.8% of LW, provides greater productive and reproductive performance for ewes and lambs.(AU)

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Foliar fertilization with macro and micro minerals for the forage grasses establishment can be a less costly alternative for the farmer, however the possible beneÀ ts of this management technique still need to be better studied. The objective with this work was to evaluate the physiological, productive and structural responses of grasses of the Urochloa genus, depending on the application or not of foliar fertilizer during the plant establishment. Four experiments were carried out, in each of which one of the following forage grasses was evaluated: Urochloa brizantha cv. Marandu, Urochloa spp. Mulatto II, Urochloa spp. Mavuno and Urochloa spp. Ipyporã. All the experiments were carried out from November 2018 to March 2019, in a completely randomized design, with four replications. The experimental area of each experiment consisted of four plots with 12.25 m², where half the area of the plots received foliar fertilizer (FH PASTAGEM FOLIAR, with 14% N; 12% P; 12% K; 0.38 % Mg; 10.2% S; 0.24% Cu; 0.18% Mn and 0.63% Zn) and the other half did not. The response variables were evaluated: spad index, leaf area index, canopy light interception, forage production and root density. In all experiments, the foliar fertilizer application during the establishment of Marandu, Mulato II, Mavuno and Ipyporã grasses did not inÁ uence (P>0,05) the spad and leaf area indexes, forage production and root density.(AU)