Chemical composition and fermentation characteristics of elephant grass silage with biodiesel industry co-products

The objective of this research was to evaluate the effect of three concentrations (3, 6, and 9%) of forage turnip (Raphanus sativus) and physic nut (Jatropha curcas) cakes on dry matter, crude protein, ether extract, neutral detergent fiber, acid detergent fiber, lignin, acid detergent insoluble nitrogen neutral detergent insoluble nitrogen contents, in vitro dry matter digestibility, pH values and concentrations of N-NH3 in elephant grass silages. It was used an entirely randomized design in factorial arrangement [(2x3)+1]. Experimental PVC silos were used and ensiled material was kept for 62 days. The addition of cakes increased the dry matter contents (P<0.05). The fibrous fractions were reduced (P<0.05) with the inclusion of cakes during the grass ensilage and the CP contents increased (P<0.05). The forage turnip cake provided the same pH and N-NH3 values in ideal levels and the physic nut, added to 9%, increased those values (P<0.05). IVDMD was reduced (P<0.05) when the cakes were added. These co-products can be used in small amounts for elephant grass ensilage in order to provide improvement in chemical and fermentation characteristics of the silages. Nevertheless, physic nut cake shows limitations for its use in animal feeding due to the presence of toxic compounds, making necessary studies for their identification and elimination.

Supplementation of Nellore young bulls on Marandu grass pastures in the dry period of the year

The objective of this study was to evaluate performance and daytime ingestive behavior of 84 Nellore young bulls in the post-weaning phase kept on Brachiaria brizantha cv. Marandu pastures during the dry season. Treatments were protein mineral supplementation (1 g/kg body weight) and protein+energy mineral supplementation (3 g/kg body weight). The experimental area comprised 12 paddocks in a total area of 27.36 ha, divided in two blocks of six paddocks each, having three replications per treatment in each block, with 42 animals/treatment. The data were subjected to variance analysis with repeated measures over time via procedure PROCMIXED of SAS (Statistical Analysis System, version 9.0) and means were compared by the Tukey test at 5% probability. The initial average weight of animals was 204.8 kg; final weights were 260.9 and 276.9 kg for animals that received protein and protein+energy supplement, respectively. The forage availability, sward height and stocking rate values did not differ with supplementation, but they showed difference between the experimental periods. The average time spent grazing during daylight of animals fed protein+energy supplement was shorter as compared with those which consumed protein supplement. Animals kept under the same pasture conditions during the dry season show better performance when they receive protein+energy supplement than protein supplement.

Bermuda grass sod production as related to nitrogen rates

O N é o nutriente que proporciona as maiores respostas no crescimento das gramas, e a adubação nitrogenada adequada pode proporcionar a formação do tapete com boa qualidade em menor tempo. Neste trabalho, objetivou-se avaliar a influência da adubação nitrogenada na produção e qualidade de tapetes de grama-bermuda. O experimento foi instalado e conduzido em área de produção comercial de grama, localizada na cidade de Capela do Alto, SP. A grama utilizada foi a Cynodon dactylon (Pers) L., conhecida como grama-bermuda. O delineamento experimental utilizado foi o de blocos casualizados, com cinco tratamentos e quatro repetições. Os tratamentos foram constituídos por cinco doses de N: 0, 150, 300, 450 e 600 kg ha-1. O aumento das doses de N aumentou a taxa de cobertura do solo pela gramabermuda, reduzindo o tempo para formação do tapete. O máximo acúmulo de matéria seca de rizomas + estolões + raízes foi proporcionado pela dose de 354 kg ha-1 de N, e a resistência dos tapetes, pela dose de 365 kg ha-1 de N. Doses de N entre 354 e 365 kg ha-1, aumentaram a resistência dos tapetes e, com isso, a capacidade deles serem manuseados após a colheita, podendo promover assim maior rendimento da área.

Growth of the Symbiotic Fungus of the Grass-cutting Ant Atta capiguara (Hymenoptera: Formicidae): Effect of Grass Extracts

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Selectivity of Workers of the Grass-Cutting Ants Atta bisphaerica and Atta capiguara (Hymenoptera: Formicidae) to Vegetable Oils

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Método não destrutivo de estimativa da área foliar de plantas daninhas de ambiente aquático: tanner-grass e capim-fino

The continuous inputs from agriculture areas and human or industrial sewer have been provided a widely demographic explosion of tropical tanner-grass and para grasss plants in the rivers and water reservoirs of Brazil. Considering the importance of these noxious weeds there is a vast necessity of basic studies on aspects related to reproduction, growing, development, nutritional requirements, responses to control systems and others. In most studies, leaf area knowledge is crucial and it is one of the most difficult characteristics to be measured because it usually requires expensive equipments or it uses a destructive technique. The objective of this work was to develop equations for leaf blade dimensional parameters to allow determination of the leaf area of African tanner-grass (Brachiaria subquadripara (Trin.) Hitchc) and para grass (Brachiaria mutica (Forsk.) Stapf.). Correlations between real leaf area and dimensional parameters of leaf blade such as length along the main vein (L) and maximum width (W) perpendicular to the main axis were studied. Only the linear equations allowed a good leaf area estimate. It is suggested to opt for a simple linear equation involving respective products of length times maximum width considering linear coefficient equal to zero. Thus, B. subquadripara (SS) and B. mutica (SM) non destructive leaf blade area estimates may be performed by the following formulas: SS = 0.7719 (L x W) and SM = 0.7479 (L x W), with coefficients of determination (R(2)) of 0.9594 and 0.9408, respectively.

Recovery of Trichostrongylus colubriformis infective larvae from three grass species contaminated in the autumn

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Vertical migration of Haemonchus contortus third stage larvae on Brachiaria decumbens grass

The present study aimed at evaluating the vertical migration of Haemonchus contortus third stage larvae (1-3) on Brachiaria decumbens grass, as well as at verifying whether larval numbers on pasture varies over the day due to climatic conditions. Feces containing H. contortus L3 were deposited on the soil in the middle of herbage which was initially 30 cm high. Seven days later, samples of different herbage strata (0-10, 10-20 and >20 cm), remaining feces and a layer of approximately 1 cm soil were collected. Tests were carried out in four periods: September 2006, December 2006, March 2007, and June 2007. Samples were collected at sunrise, mid-day, sunset, and mid-night. The humidity and temperature conditions observed in different months influenced larval migration from the feces to the grass. In September, December and March, it rained after fecal deposition on pasture, which favored migration of larvae from the feces to the herbage. Conversely, in June 2007, when there was no rainfall after fecal deposition and temperatures were lower, L3 were mainly recovered from feces. As regards the vertical migration of larvae, the numbers of H. contortus L3 in the forage strata remained relatively constant over the day. This indicates there is not a determined period in which sheep on pasture are at higher risk of infection. Finally, in all collection periods a considerable amount of third stage larvae was observed on the herbage top, which is the first plant part consumed by sheep. (C) 2008 Elsevier B.V. All rights reserved.

Reproductive morphology of the early-divergent grass Streptochaeta and its bearing on the homologies of the grass spikelet

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Microsporogenesis is simultaneous in the early-divergent grass Streptochaeta, but successive in the closest grass relative, Ecdeiocolea

Simultaneous microsporogenesis is described for the first time in a grass, Streptochaeta spicata Schrad., a tropical Brazilian species that belongs in the early-divergent subfamily Anomochlooideae. Microsporogenesis is successive in all other Poaceae examined so far, and most other members of the order Poales, to which grasses belong. The only other reports of simultaneous microsporogenesis in Poales are in Rapateaceae and some members of the cyperid clade (Juncaceae, Cyperaceae, Prionium and Thurnia). Among the graminids, Ecdeiocolea (the putative closest relative to Poaceae) is successive, as are Joinvillea, Flagellaria and all other Poaceae, indicating that the simultaneous condition is autapomorphic in Streptochaeta, though Anomochloa has yet to be examined. Anther wall development in Streptochaeta is of the reduced type, as also in another early-divergent grass Pharus, though most other Poales, including most grasses, have the monocot type. In Streptochaeta, as in Pharus, the endothecium lacks thickenings, unlike other grasses that have a persistent endothecium with thickenings. The centrifixed anthers and nonplumose stigmas of Streptochaeta suggest entomophily.

Use of sugarcane bagasse and grass hydrolysates as carbon sources for xylanase production by Bacillus circulans D1 in submerged fermentation

The use of sugarcane bagasse and grass as low cost raw material for xylanase production by Bacillus circulans D1 in submerged fermentation was investigated. The microorganism was cultivated in a mineral medium containing hydrolysate of bagasse or grass as carbon source. High production of enzyme was obtained during growth in media with bagasse hydrolysates (8.4 U/mL) and in media with grass hydrolysates (7.5 U/mL). Xylanase production in media with hydrolysates was very close to that obtained in xylan containing media (7.0 U/ mL) and this fact confirm the feasibility of using this agro-industrial byproducts by B. circulans D1 as an alternative to save costs on the enzyme production process. (c) 2005 Elsevier Ltd. All rights reserved.

Grass-dominated stream sites exhibit low fish species diversity and dominance by guppies: an assessment of two tropical pasture river basins

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Indirect method for quantifying the content of photosynthetic pigments in genotypes of dwarf elephant grass

O objetivo deste ensaio foi determinar equações que indiretamente associem os valores obtidos no medidor de clorofila SPAD-502 aos teores de clorofila e carotenóides de genótipos de capim-elefante anão. Folhas de genótipos de capim-elefante anão foram utilizadas e, depois de coletadas, foram transportadas em caixas de isopor, protegidas da luz, até o laboratório de Fisiologia Vegetal da UENF. Posteriormente, os discos foliares de área conhecida foram extraídos. Com o auxílio do medidor portátil de clorofila (MPC) SPAD-502, foi obtida a média de 5 leituras/disco foliar e utilizaram-se 6 discos para cada intervalo, distribuídos de acordo com a seguinte escala de valores do MPC: 0-10; 10-20; 20-30; 30-40; 40-50; 50-60. O medidor de clorofila SPAD-502 possibilitou uma rápida e eficaz estimativa do conteúdo de clorofila total, clorofila-a e clorofila-b em genótipos de capim-elefante anão.

Daily intake of lactating crossbred cows grazing elephant grass rotationally

O objetivo deste trabalho foi o de estimar o consumo total e o diário de matéria seca do pasto, de vacas mestiças Holandês - Zebu, em piquetes de capim-elefante (Pennisetum purpureum Schum.). Três grupos de 24 vacas foram usados em piquetes (4,5 vacas/ha), pastejados por três dias e submetidos a diferentes períodos de descanso durante dois anos. Os tratamentos consistiram de descansos de 30 dias sem concentrado e 30, 37,5 e 45 dias com a suplementação de 2 kg de concentrado (20,6% de proteína bruta). de julho a outubro, as vacas receberam, como suplementação, cana-de-açúcar mais 1% de uréia. O consumo total de matéria seca foi estimado a partir da digestibilidade in vitro da matéria seca da extrusa e da produção fecal obtida com óxido crômico. Independentemente do tratamento, o consumo total foi 2,7; 2,9 e 2.9±0,03%, e o consumo de matéria seca do pasto foi de 1,9; 2,1 e 2,1±0,03% do peso vivo (p<0,05), respectivamente, no primeiro, segundo e terceiro dia de ocupação do piquete. Somente no verão, o consumo do pasto foi semelhante nos três dias de pastejo. A mistura cana-de-açúcar e uréia substituiu o pasto, principalmente no primeiro dia de pastejo, ocasião em que o consumo do pasto era mais baixo.