Effects of supplementation with corn distillers' dried grains on animal performance, nitrogen balance, and enteric CH4 emissions of young Nellore bulls fed a high-tropical forage diet.

The inclusion of corn-dried distillers' grains (DDG) could be an alternative supplement to increase animal performance, nitrogen efficiency usage (NEU), and decrease enteric methane (CH4) emissions. Our goal was to determine whether DDG could replace a traditional supplement (cottonseed meal) without affecting animal performance, N balance, and CH4 emissions. The experiment was conducted during the forage growing season (December to April), with 15 d adaptation, and a 112 d experimental period. The experimental design was completely randomized with four treatments: a mineral supplement (MS), cottonseed meal supplement (CS), 50% replacement of CS by DDG (50DDG), and 100% replacement of CS by DDG (100DDG). Cottonseed meal and DDG were used as protein supplement. A total of 12 paddocks, 3 per treatment, were used to measure forage mass: morphological and chemical composition of forage, forage allowance, and animal performance. Six animals per treatment were used to evaluate DM intake, digestibility, CH4 emissions, microbial protein production (MCP), and NEU of each treatment. Eighty-one Young Nellore bulls (48 testers, 12 per treatments and 33 adjusters) with initial BW of 255 ±â€¯5 kg (10-12 months old) were supplemented with each supplement type at a level of 0.3% of BW. Pasture management was continuous stocking with a variable stocking rate (put-and-take). Enteric CH4 was measured using the gas tracer technique. The MCP was quantified using purine derivatives and the NEU mass balance. No differences were found in nutrient intake (P > 0.228). Individual animal performance and gain per area were higher in the treatments with concentrates compared with that of MS; however, there was no difference among treatments CS, 50DDG, and 100DDG. The ADG was 0.83 for MS and 1.08 kg/animal/d when supplemented (P < 0.05). Gain per hectare was 709 kg/ha for MS and 915 kg/ha when supplemented with concentrates (P < 0.05). There was no difference in CH4 production among treatments that average 180 g/animal/d; however, CH4 per kg of gain was reduced with CS. The CH4 conversion factor averaged 5.91%. There was no difference in the synthesis of MCP and NEU. Corn DDG can replace 100% of cottonseed meal as a protein source for supplementation of young Nellore bulls grazing in tropical pastures without affecting animal performance, NEU, MCP, and CH4 emissions.

Sward structure and ingestive behavior of cows in tropical pastures managed under different forage allowances / Estrutura do dossel forrageiro e comportamento ingestivo de vacas em pastos tropicais manejados sob diferentes ofertas de forragem

This study evaluated how changing the structure of Brachiaria brizantha cv. Marandu pasture under different forage allowances (FA) of 4, 7, 10 and 13kg DM/100kg BW (body weight) affected animal behavior over a two-year evaluation period. The experiment was conducted as a randomized block design with three replications (paddock). Sward height, total forage, and stem mass were lower for pastures managed with lower FA. Lower leaf mass was observed for lower FA in the second year. In hand-plucked samples, leaf and stem percentages remained unchanged in the morning but leaf percentage increased while stems decreased in the afternoon. Permanence time decreased linearly with increasing FA. In turn, a quadratic effect was observed for displacement rate. The bite rate was similar among different FAs. The results demonstrate that FA varying between 7 and 10kg DM/100kg BW are more suitable to balance the amounts of leaves and stems in the sward. The studied FA levels do not limit forage availability. Permanence time decreases and displacement rate increases as FA increases.(AU)

O objetivo foi avaliar como mudanças na estrutura de pastos de Brachiaria brizantha cv. Marandu, sob diferentes ofertas de forragem (OF) de 4, 7, 10 e 13kg MS/100kg PC, afetam o comportamento animal durante um período de avaliação de dois anos. O delineamento utilizado foi em blocos ao acaso, com três repetições (piquetes). A altura do dossel, a massa de forragem total e de colmos foram menores em pastos manejados com menores OF. A menor massa de folhas foi observada na menor OF no segundo ano. Nas amostras de pastejo simulado, as porcentagens de folhas e colmos não diferiram pela manhã, mas a porcentagem de folhas aumentou, enquanto a de colmos diminuiu à tarde. O tempo de permanência dos animais diminuiu linearmente com o aumento das OF. Efeito quadrático foi observado para taxa de deslocamento. A taxa de bocados foi similar entre as OF. Os resultados demonstram que variar as OF entre 7 e 10kg MS/100kg PC é mais adequado para balancear as quantidades de folhas e colmos no dossel forrageiro. Os níveis de OF estudados não limitam a forragem disponível. O tempo de permanência diminuí e a taxa de deslocamento aumenta com o aumento das OF.(AU)

Sward structure and ingestive behavior of cows in tropical pastures managed under different forage allowances / Estrutura do dossel forrageiro e comportamento ingestivo de vacas em pastos tropicais manejados sob diferentes ofertas de forragem

This study evaluated how changing the structure of Brachiaria brizantha cv. Marandu pasture under different forage allowances (FA) of 4, 7, 10 and 13kg DM/100kg BW (body weight) affected animal behavior over a two-year evaluation period. The experiment was conducted as a randomized block design with three replications (paddock). Sward height, total forage, and stem mass were lower for pastures managed with lower FA. Lower leaf mass was observed for lower FA in the second year. In hand-plucked samples, leaf and stem percentages remained unchanged in the morning but leaf percentage increased while stems decreased in the afternoon. Permanence time decreased linearly with increasing FA. In turn, a quadratic effect was observed for displacement rate. The bite rate was similar among different FAs. The results demonstrate that FA varying between 7 and 10kg DM/100kg BW are more suitable to balance the amounts of leaves and stems in the sward. The studied FA levels do not limit forage availability. Permanence time decreases and displacement rate increases as FA increases.(AU)

O objetivo foi avaliar como mudanças na estrutura de pastos de Brachiaria brizantha cv. Marandu, sob diferentes ofertas de forragem (OF) de 4, 7, 10 e 13kg MS/100kg PC, afetam o comportamento animal durante um período de avaliação de dois anos. O delineamento utilizado foi em blocos ao acaso, com três repetições (piquetes). A altura do dossel, a massa de forragem total e de colmos foram menores em pastos manejados com menores OF. A menor massa de folhas foi observada na menor OF no segundo ano. Nas amostras de pastejo simulado, as porcentagens de folhas e colmos não diferiram pela manhã, mas a porcentagem de folhas aumentou, enquanto a de colmos diminuiu à tarde. O tempo de permanência dos animais diminuiu linearmente com o aumento das OF. Efeito quadrático foi observado para taxa de deslocamento. A taxa de bocados foi similar entre as OF. Os resultados demonstram que variar as OF entre 7 e 10kg MS/100kg PC é mais adequado para balancear as quantidades de folhas e colmos no dossel forrageiro. Os níveis de OF estudados não limitam a forragem disponível. O tempo de permanência diminuí e a taxa de deslocamento aumenta com o aumento das OF.(AU)

Morpho-physiological profile of Marandu palisade grass managed under different forage allowance and grazed by dairy cows / Perfil morfofisiológico de capim-Marandu manejado sob diferentes ofertas de forragem e pastejado por vacas leiteiras

The study was conducted to evaluate the morphological composition of pastures, and the chemical composition of leaves and stems of Marandu grass managed under forage allowances of 4, 7, 10 and 13 kg per 100 kg of live weight (LW). Grazing was done by Holstein cows, and the method adopted was rotated stocking with variable stocking rate and rest period of 21 days. Collection of samples was conducted by double sampling. Stocking adjustment of each plot was made according to green dry forage mass, plot area, and the forage allowance desired. The percentage of leaves varies (P 0.05) between the forage allowances, however they varied during the experimental period, with lower (P <0.05) stem percentages and greater (P < 0.05) percentage of dead material in the third and fourth GC. There was an interaction (P < 0.05) between forage allowance and GC for crude protein (CP) content in the leaves. In the stems, CP content decreased with the increasing forage allowance. Cell wall components contents were similar among the forage allowances both in the leaves and in the stems, but there was variation in the levels of the different components over the GC. Thus, the definition of an adequate forage allowance must consider the climatic conditions of the region and the time of year.

O estudo foi conduzido com o objetivo de avaliar a composição morfológica dos pastos e a composição química das folhas e colmos de capim-Marandu manejados sob as ofertas de forragem de 4, 7, 10 e 13 kg por 100 kg de peso vivo (PV). O pastejo foi realizado por vacas da raça Holandesa e o método adotado foi rotacionado, com taxa de lotação variável e período de descanso de 21 dias. A coleta de amostras foi realizada por dupla amostragem. O ajuste da carga animal de cada parcela foi feito de acordo com a massa de forragem verde seca, a área da parcela e a oferta de forragem pretendida. A porcentagem de folhas variou (P < 0,05) em função da interação entre ofertas de forragem e ciclos de pastejo (CP), apresentando comportamento diferente para cada oferta. As porcentagens de colmos e material morto não diferiram entre as ofertas de forragem, porém variaram ao longo do período experimental com menores (P < 0,05) porcentagens de colmos e maiores (P < 0,05) de material morto no terceiro e quarto CP. Houve interação (P < 0,05) entre oferta de forragem e CP sobre o teor de proteína bruta (PB) nas folhas. Já nos colmos, os teores de PB diminuíram com o aumento das ofertas. Os teores de componentes da parede celular foram semelhantes entre as ofertas, tanto nas folhas quanto nos colmos, porém ocorreu variação nos teores dos diferentes componentes ao longo dos CP. Dessa forma,podemos inferir que a composição morfológica dos pastos de capim-Marandu é alterada tanto pelas ofertas de forragem quanto pelos CP. O mesmo acontece com os teores de PB. Por outro lado, os diferentes componentes da parede celular são modificados pelo decorrer do período experimental. Dessa forma, a definição de uma oferta de forragem adequada deve considerar as condições climáticas da região e a época do ano.

PERFIL MORFOFISIOLÓGICO DE CAPIM-MARANDU MANEJADO SOB DIFERENTES OFERTAS DE FORRAGEM E PASTEJADO POR VACAS LEITEIRAS

O estudo foi conduzido com o objetivo de avaliar a composição morfológica dos pastos e a composição química das folhas e colmos de capim-Marandu manejados sob as ofertas de forragem de 4, 7, 10 e 13 kg por 100 kg de peso vivo (PV). O pastejo foi realizado por vacas da raça Holandesa e o método adotado foi rotacionado, com taxa de lotação variável e período de descanso de 21 dias. A coleta de amostras foi realizada por dupla amostragem. O ajuste da carga animal de cada parcela foi feito de acordo com a massa de forragem verde seca, a área da parcela e a oferta de forragem pretendida. A porcentagem de folhas variou (P

Morpho-physiological profile of Marandu palisade grass managed under different forage allowance and grazed by dairy cows / Perfil morfofisiológico de capim-Marandu manejado sob diferentes ofertas de forragem e pastejado por vacas leiteiras

The study was conducted to evaluate the morphological composition of pastures, and the chemical composition of leaves and stems of Marandu grass managed under forage allowances of 4, 7, 10 and 13 kg per 100 kg of live weight (LW). Grazing was done by Holstein cows, and the method adopted was rotated stocking with variable stocking rate and rest period of 21 days. Collection of samples was conducted by double sampling. Stocking adjustment of each plot was made according to green dry forage mass, plot area, and the forage allowance desired. The percentage of leaves varies (P < 0.05) due to the interaction between forage allowance and grazing cycles (GC) with different behavior for each forage allowance. The percentage of stems and dead material did not differ (P>0.05) between the forage allowances, however they varied during the experimental period, with lower (P <0.05) stem percentages and greater (P < 0.05) percentage of dead material in the third and fourth GC. There was an interaction (P < 0.05) between forage allowance and GC for crude protein (CP) content in the leaves. In the stems, CP content decreased with the increasing forage allowance. Cell wall components contents were similar among the forage allowances both in the leaves and in the stems, but there was variation in the levels of the different components over the GC. Thus, the definition of an adequate forage allowance must consider the climatic conditions of the region and the time of year.(AU)

O estudo foi conduzido com o objetivo de avaliar a composição morfológica dos pastos e a composição química das folhas e colmos de capim-Marandu manejados sob as ofertas de forragem de 4, 7, 10 e 13 kg por 100 kg de peso vivo (PV). O pastejo foi realizado por vacas da raça Holandesa e o método adotado foi rotacionado, com taxa de lotação variável e período de descanso de 21 dias. A coleta de amostras foi realizada por dupla amostragem. O ajuste da carga animal de cada parcela foi feito de acordo com a massa de forragem verde seca, a área da parcela e a oferta de forragem pretendida. A porcentagem de folhas variou (P < 0,05) em função da interação entre ofertas de forragem e ciclos de pastejo (CP), apresentando comportamento diferente para cada oferta. As porcentagens de colmos e material morto não diferiram entre as ofertas de forragem, porém variaram ao longo do período experimental com menores (P < 0,05) porcentagens de colmos e maiores (P < 0,05) de material morto no terceiro e quarto CP. Houve interação (P < 0,05) entre oferta de forragem e CP sobre o teor de proteína bruta (PB) nas folhas. Já nos colmos, os teores de PB diminuíram com o aumento das ofertas. Os teores de componentes da parede celular foram semelhantes entre as ofertas, tanto nas folhas quanto nos colmos, porém ocorreu variação nos teores dos diferentes componentes ao longo dos CP. Dessa forma,podemos inferir que a composição morfológica dos pastos de capim-Marandu é alterada tanto pelas ofertas de forragem quanto pelos CP. O mesmo acontece com os teores de PB. Por outro lado, os diferentes componentes da parede celular são modificados pelo decorrer do período experimental. Dessa forma, a definição de uma oferta de forragem adequada deve considerar as condições climáticas da região e a época do ano. (AU)

The endocannabinoid system in renal cells: regulation of Na(+) transport by CB1 receptors through distinct cell signalling pathways.

BACKGROUND AND PURPOSE: The function of the endocannabinoid system (ECS) in renal tissue is not completely understood. Kidney function is closely related to ion reabsorption in the proximal tubule, the nephron segment responsible for the re-absorption of 70-80% of the filtrate. We studied the effect of compounds modulating the activity of cannabinoid (CB) receptors on the active re-absorption of Na(+) in LLC-PK1 cells. EXPERIMENTAL APPROACH: Changes in Na(+) /K(+) -ATPase activity were assessed after treatment with WIN55,212-2 (WIN), a non-selective lipid agonist, and haemopressin (HP), an inverse peptide agonist at CB1 receptors. Pharmacological tools were used to investigate the signalling pathways involved in the modulation of Na(+) transport. KEY RESULTS: In addition to CB1 and CB2 receptors and TRPV1 channels, the mRNAs encoding for enzymes of the ECS were also expressed in LLC-PK1. WIN (10(-7) M) and HP (10(-6) M) altered Na(+) re-absorption in LLC-PK1 in a dual manner. They both acutely (after 1 min) increased Na(+) /K(+) -ATPase activity in a TRPV1 antagonist-sensitive way. WIN's stimulating effect persisted for 30 min, and this effect was partially blocked by a CB1 antagonist or a PKC inhibitor. In contrast, HP inhibited Na(+) /K(+) -ATPase after 30 min incubation, and this effect was attenuated by a CB1 antagonist or a PKA inhibitor. CONCLUSION AND IMPLICATIONS: The ECS is expressed in LLC-PK1 cells. Both CB1 receptors and TRPV1 channels regulate Na(+) /K(+) -ATPase activity in these cells, and are modulated by lipid and peptide CB1 receptor ligands, which act via different signalling pathways.

Plantas do Gênero Xylopia: Composição Química e Potencial Farmacológico / Plants of the Xylopia Genus: Chemical Composition and Pharmacological Potential

RESUMO A família Annonaceae possui representantes de grande interesse medicinal e o gênero Xylopia é um dos que merecem destaque. Composta por aproximadamente 160 espécies distribuídas na América do Sul, América central, África e Ásia, as espécies desse gênero podem ser arbustivas ou arbóreas. No Brasil são encontradas nas regiões Norte, Nordeste, Centro-Oeste e Centro Sul. Este gênero produz uma variedade de metabólitos incluindo alcalóides, amidas, lignóides, acetogeninas e terpenóides e têm sido investigados como fonte potencial de acetogeninas, compostos esses que apresentam uma ampla variedade de propriedades biológicas com destaque para: citotóxica, antitumoral, antiparasitária, antimicrobial, inseticida e antimalarial. Neste estudo, efetuou-se uma revisão das principais espécies de Xylopiaencontradas no Brasil, já estudadas e descritas na literatura, abordando os aspectos químico-farmacológicos, destacando os constituintes químicos isolados bem como a ação farmacológica evidenciada.

ABSTRACT The family Annonaceae has representatives of great medical interest, and the Xylopia species deserves attention. The Xylopia genus is composed by approximately 160 species, with geographic distribution in tropical and subtropical regions of America, Africa and Asia. This genus can present shrubs or trees. In Brazil, they can be found at the North, North-west, Central-West and Central-South Regions. The phytochemical investigations resulted mainly in the isolation of alkaloids, diterpenos, quinolines and acetogenins, with the latter presenting very interesting biological properties such as the cytotoxic, antiprotozoal and the insecticide activities.This study aimed to review the botanical, chemical and pharmacological aspects of the Xylopia genus found in Brazil, highlighting the chemical components, as the well-known pharmacological effect .

Oxidative stress on cardiotoxicity after treatment with single and multiple doses of doxorubicin.

The mechanism of doxorubicin (DOX)-induced cardiotoxicity remains controversial. Wistar rats (n = 66) received DOX injections intraperitoneally and were randomly assigned to 2 experimental protocols: (1) rats were killed before (-24 h, n = 8) and 24 h after (+24 h, n = 8) a single dose of DOX (4 mg/kg body weight) to determine the DOX acute effect and (2) rats (n = 58) received 4 injections of DOX (4 mg/kg body weight/week) and were killed before the first injection (M0) and 1 week after each injection (M1, M2, M3, and M4) to determine the chronological effects. Animals used at M0 (n = 8) were also used at moment -24 h of acute study. Cardiac total antioxidant performance (TAP), DNA damage, and morphology analyses were carried out at each time point. Single dose of DOX was associated with increased cardiac disarrangement, necrosis, and DNA damage (strand breaks (SBs) and oxidized pyrimidines) and decreased TAP. The chronological study showed an effect of a cumulative dose on body weight (R = -0.99, p = 0.011), necrosis (R = 1.00, p = 0.004), TAP (R = 0.95, p = 0.049), and DNA SBs (R = -0.95, p = 0.049). DNA SBs damage was negatively associated with TAP (R = -0.98, p = 0.018), and necrosis (R = -0.97, p = 0.027). Our results suggest that oxidative damage is associated with acute cardiotoxicity induced by a single dose of DOX only. Increased resistance to the oxidative stress is plausible for the multiple dose of DOX. Thus, different mechanisms may be involved in acute toxicity versus chronic toxicity.

Substituição de monensina sódica por bicarbonato de sódio em dietas de novilhas confinadas / Evaluation of the replacement of Monensin with Sodium Bicarbonate in diets for confined bovines

Avaliaram-se os efeitos da substituição da monensina sódica pelo bicarbonato de sódio em dietas de novilhas em confinamento em relação ao desempenho animal, à conversão alimentar e ao parâmetro de fermentação ruminal. Foram utilizadas 56 novilhas mestiças, confinadas por 112 dias, submetidas a dietas com duas porcentagens de concentrado, 50% e 80% da matéria seca, com adição de monensina sódica ou bicarbonato de sódio, em fatorial 2x2. O volumoso utilizado para compor as dietas testadas foi composto de silagem de milho e cana-de-açúcar na proporção de 60:40, respectivamente. O nitrogênio amoniacal foi maior nos animais alimentos com dietas com alto grão. A monensina, na dieta 80:20, proporcionou maiores valores de nitrogênio amoniacal, uma e nove horas após o consumo da ração. O uso de bicarbonato promoveu os maiores valores de pH ruminal na dieta com 50% de concentrado, de seis a 18 horas após o consumo. Não houve efeito do aditivo sobre o desempenho animal. A alta inclusão de grãos na dieta propiciou aumento do desempenho animal e da eficiência alimentar. Conclui-se que o uso de bicarbonato de sódio em dietas para terminação de animais em confinamento é uma opção viável em substituição à monensina sódica para a manipulação da fermentação ruminal.

The effects of replacing monensin with sodium bicarbonate in diets for confined heifers on weight gain (WG), dry matter intake (DMI), feed:gain ratio (FGR) and rumen fermentation parameters were evaluated. Fifity six heifers were utilized (Santa Gertrudis x Braunvieh). Diets were formulated with two levels of concentrate (50% and 80% concentrate) with sodium monensin or sodium bicarbonate. The DMI was higest in heifers with an intake of 80% concentrate. There was not difference when the same concentrate levels were evaluated in relation to the DMI. The heifers at 80% concentrate showed highest WG. There was no significant difference in relation to WG between monensin and bicarbonate treatments and levels concentrate proportions. There were significant effects regarding FGR between treatments. The heifers on 80% concentrate showed lowest FGR. In the evaluation of N-NH3, the highest values were observed, on the whole, at 80:20 diets in relation to 50:50 diets. In the additive use, the monensin on 80:20 diets promoted the highest values of N-NH3 at 1 for 9 hours after feed intake. In the values of ruminal pH, the bicarbonate increased the values on 50:50 at 6 for18 hours after feed intake, in relation to the 80:20 diet. In this case, it was concluded that the use of sodium bicarbonate in diets for confined finishing heifers is a viable option for the replacement of monensin sodium.

Substituição de monensina sódica por bicarbonato de sódio em dietas de novilhas confinadas / Evaluation of the replacement of Monensin with Sodium Bicarbonate in diets for confined bovines

Avaliaram-se os efeitos da substituição da monensina sódica pelo bicarbonato de sódio em dietas de novilhas em confinamento em relação ao desempenho animal, à conversão alimentar e ao parâmetro de fermentação ruminal. Foram utilizadas 56 novilhas mestiças, confinadas por 112 dias, submetidas a dietas com duas porcentagens de concentrado, 50% e 80% da matéria seca, com adição de monensina sódica ou bicarbonato de sódio, em fatorial 2x2. O volumoso utilizado para compor as dietas testadas foi composto de silagem de milho e cana-de-açúcar na proporção de 60:40, respectivamente. O nitrogênio amoniacal foi maior nos animais alimentos com dietas com alto grão. A monensina, na dieta 80:20, proporcionou maiores valores de nitrogênio amoniacal, uma e nove horas após o consumo da ração. O uso de bicarbonato promoveu os maiores valores de pH ruminal na dieta com 50% de concentrado, de seis a 18 horas após o consumo. Não houve efeito do aditivo sobre o desempenho animal. A alta inclusão de grãos na dieta propiciou aumento do desempenho animal e da eficiência alimentar. Conclui-se que o uso de bicarbonato de sódio em dietas para terminação de animais em confinamento é uma opção viável em substituição à monensina sódica para a manipulação da fermentação ruminal.(AU)

The effects of replacing monensin with sodium bicarbonate in diets for confined heifers on weight gain (WG), dry matter intake (DMI), feed:gain ratio (FGR) and rumen fermentation parameters were evaluated. Fifity six heifers were utilized (Santa Gertrudis x Braunvieh). Diets were formulated with two levels of concentrate (50% and 80% concentrate) with sodium monensin or sodium bicarbonate. The DMI was higest in heifers with an intake of 80% concentrate. There was not difference when the same concentrate levels were evaluated in relation to the DMI. The heifers at 80% concentrate showed highest WG. There was no significant difference in relation to WG between monensin and bicarbonate treatments and levels concentrate proportions. There were significant effects regarding FGR between treatments. The heifers on 80% concentrate showed lowest FGR. In the evaluation of N-NH3, the highest values were observed, on the whole, at 80:20 diets in relation to 50:50 diets. In the additive use, the monensin on 80:20 diets promoted the highest values of N-NH3 at 1 for 9 hours after feed intake. In the values of ruminal pH, the bicarbonate increased the values on 50:50 at 6 for18 hours after feed intake, in relation to the 80:20 diet. In this case, it was concluded that the use of sodium bicarbonate in diets for confined finishing heifers is a viable option for the replacement of monensin sodium.(AU)

Digestibilidade aparente da dieta com capim-elefante ensilado com diferentes aditivos / Apparent digestibility of diet with elephant grass ensiled with different additives

Foram estudados os efeitos da adição de 15 por cento de diferentes aditivos - casca de café, farelo de cacau e farelo de mandioca - à forragem verde de capim-elefante (peso/peso), no momento da ensilagem, sobre a digestibilidade aparente de dietas. Foram usados 20 ovinos machos, não castrados, com média de 22,27±3,24kg de peso corporal, em um delineamento inteiramente ao acaso, com quatro tratamentos e cinco repetições. Os tratamentos foram: T1 = capim-elefante ensilado sem aditivo; T2 = capim-elefante ensilado com 15 por cento de casca de café; T3 = capim-elefante ensilado com 15 por cento de farelo de cacau; T4 = capim-elefante ensilado com 15 por cento de farelo de mandioca. Os animais receberam dieta isoproteica (10 por cento de proteína bruta) em proporção de 60 por cento de volumoso e 40 por cento de concentrado, na base da matéria seca. Utilizou-se o método de coleta total de fezes durante sete dias. Os coeficientes de digestibilidade aparente da matéria seca, proteína bruta, fibra em detergente neutro e fibra em detergente ácido e de digestibilidade verdadeira da proteína bruta foram maiores no capim-elefante ensilado sem aditivo. O coeficiente de digestibilidade do extrato etéreo foi mais alto na silagem sem aditivo e na silagem com farelo de cacau. Os coeficientes de digestibilidade da matéria orgânica e dos carboidratos totais foram mais elevados na silagem sem aditivo e na silagem com farelo de mandioca. Os maiores valores de nutrientes digestíveis totais foram observados nas dietas que continham silagem sem aditivo e silagem com farelo de mandioca. A silagem de capim-elefante com 15 por cento de farelo de mandioca, bem como a silagem sem aditivo apresentaram melhor digestibilidade dos nutrientes.

The effects of adding 15 percent of different additives (coffee hulls, cocoa meal and, cassava meal) to green elephant grass forage (weight/weight) at the time of ensiling on the apparent digestibility of diets were studied using 20 male sheep in a completely randomized design, with four treatments and five replications. The treatments were: T1 = elephant grass ensiled without additive; T2 = elephant grass ensiled with 15 percent coffee hulls; T3 = elephant grass ensiled with 15 percent cocoa meal; and T4 = elephant grass ensiled with 15 percent cassava meal. The animals were fed isonitrogen diet (10 percent crude protein) in 60 percent roughage and 40 percent concentrate rate, on dry matter basis. Total feces collection method was used for seven days. The apparent digestibility coefficients of dry matter, crude protein, neutral detergent fiber, and acid detergent fiber and the true digestibility coefficient of crude protein were higher in elephant grass ensiled without additive. The ether extract digestibility coefficient was higher in the silages without additive and with cocoa meal. The digestibility coefficients of organic matter and total carbohydrates were higher in the silage without additive and in the silage with cassava meal. The highest values of total digestible nutrients were observed in diets containing silages without additive and with cassava meal. The elephant grass silage with 15 percent cassava meal, together with the silage without additive, showed better nutrients digestibility.

Digestibilidade aparente da dieta com capim-elefante ensilado com diferentes aditivos / Apparent digestibility of diet with elephant grass ensiled with different additives

Foram estudados os efeitos da adição de 15 por cento de diferentes aditivos - casca de café, farelo de cacau e farelo de mandioca - à forragem verde de capim-elefante (peso/peso), no momento da ensilagem, sobre a digestibilidade aparente de dietas. Foram usados 20 ovinos machos, não castrados, com média de 22,27±3,24kg de peso corporal, em um delineamento inteiramente ao acaso, com quatro tratamentos e cinco repetições. Os tratamentos foram: T1 = capim-elefante ensilado sem aditivo; T2 = capim-elefante ensilado com 15 por cento de casca de café; T3 = capim-elefante ensilado com 15 por cento de farelo de cacau; T4 = capim-elefante ensilado com 15 por cento de farelo de mandioca. Os animais receberam dieta isoproteica (10 por cento de proteína bruta) em proporção de 60 por cento de volumoso e 40 por cento de concentrado, na base da matéria seca. Utilizou-se o método de coleta total de fezes durante sete dias. Os coeficientes de digestibilidade aparente da matéria seca, proteína bruta, fibra em detergente neutro e fibra em detergente ácido e de digestibilidade verdadeira da proteína bruta foram maiores no capim-elefante ensilado sem aditivo. O coeficiente de digestibilidade do extrato etéreo foi mais alto na silagem sem aditivo e na silagem com farelo de cacau. Os coeficientes de digestibilidade da matéria orgânica e dos carboidratos totais foram mais elevados na silagem sem aditivo e na silagem com farelo de mandioca. Os maiores valores de nutrientes digestíveis totais foram observados nas dietas que continham silagem sem aditivo e silagem com farelo de mandioca. A silagem de capim-elefante com 15 por cento de farelo de mandioca, bem como a silagem sem aditivo apresentaram melhor digestibilidade dos nutrientes.(AU)

The effects of adding 15 percent of different additives (coffee hulls, cocoa meal and, cassava meal) to green elephant grass forage (weight/weight) at the time of ensiling on the apparent digestibility of diets were studied using 20 male sheep in a completely randomized design, with four treatments and five replications. The treatments were: T1 = elephant grass ensiled without additive; T2 = elephant grass ensiled with 15 percent coffee hulls; T3 = elephant grass ensiled with 15 percent cocoa meal; and T4 = elephant grass ensiled with 15 percent cassava meal. The animals were fed isonitrogen diet (10 percent crude protein) in 60 percent roughage and 40 percent concentrate rate, on dry matter basis. Total feces collection method was used for seven days. The apparent digestibility coefficients of dry matter, crude protein, neutral detergent fiber, and acid detergent fiber and the true digestibility coefficient of crude protein were higher in elephant grass ensiled without additive. The ether extract digestibility coefficient was higher in the silages without additive and with cocoa meal. The digestibility coefficients of organic matter and total carbohydrates were higher in the silage without additive and in the silage with cassava meal. The highest values of total digestible nutrients were observed in diets containing silages without additive and with cassava meal. The elephant grass silage with 15 percent cassava meal, together with the silage without additive, showed better nutrients digestibility.(AU)

Large-conductance channel formation mediated by P2X7 receptor activation is regulated through distinct intracellular signaling pathways in peritoneal macrophages and 2BH4 cells.

The P2X(7) receptor (P2X7R) is a ligand-gated ATP receptor that acts as a low- and large-conductance channel (pore) and is known to be coupled to several downstream effectors. Recently, we demonstrated that the formation of a large-conductance channel associated with the P2X(7) receptor is induced by increasing the intracellular Ca(2+) concentration (Faria et al., Am J Physiol Cell Physiol 297:C28-C42, 2005). Here, we investigated the intracellular signaling pathways associated with P2X(7) large-conductance channel formation using the patch clamp technique in conjunction with fluorescent imaging and flow cytometry assays in 2BH4 cells and peritoneal macrophages. Different antagonists were applied to investigate the following pathways: Ca(2+)-calmodulin, phospholipase A, phospholipase D, phospholipase C, protein kinase C (PKC), mitogen-activated protein kinase (MAPK), MAPK/extracellular signal-regulated kinase, phosphoinositide 3-kinase (PI3K), and cytoskeletal proteins. Macroscopic ionic currents induced by 1 mM ATP were reduced by 85% in the presence of PKC antagonists. The addition of antagonists for MAPK, PI3K, and the cytoskeleton (actin, intermediary filament, and microtubule) blocked 92%, 83%, and 95% of the ionic currents induced by 1 mM ATP, respectively. Our results show that PKC, MAPK, PI3K, and cytoskeletal components are involved in P2X(7) receptor large-channel formation in 2BH4 cells and peritoneal macrophages.

Degradabilidade ruminal da matéria seca, da proteína bruta e da fração fibrosa de silagens de milho, de sorgo e de Brachiaria brizantha / Ruminal degradability of dry matter, crud protein, and fiber fraction of silages of corn, sorghum, and Brachiaria brizantha

Avaliou-se a degradação da matéria seca (MS), da proteína bruta (PB), da fibra em detergente neutro (FDN), da fibra em detergente ácido (FDA) e da hemicelulose das silagens de milho, de sorgo e de Brachiaria brizantha. Foram utilizados três novilhos Nelore, machos, fistulados no rúmen, com média de peso de 200kg. Em cada animal foram incubadas amostras das três silagens nos tempos de 0, 6, 12, 24, 36, 48, 72 e 96 horas. Para as degradabilidades potencial e efetiva da MS (taxa de passagem no rúmen de 5 por cento/h), a silagem de milho foi a que apresentou valores mais altos, 80,1 e 56,7 por cento, respectivamente, seguida da silagem de sorgo, 73,0 e 45,3 por cento, e da silagem de Brachiaria, 60,8 e 33,7 por cento. Para a PB, o maior valor de degradabilidade foi verificado para a silagem de milho, 87,0 por cento, seguida das silagens de sorgo, 81,8 por cento, e de Brachiaria, 75,2 por cento. A degradabilidade da FDN foi maior para as silagens de milho e sorgo. Para FDA, a silagem de sorgo apresentou perfil de degradação menor que a silagem de milho. Os resultados sugerem melhor qualidade da silagem de milho, seguida pela do sorgo e pela de Brachiaria.

The experiment evaluated the degradation of the dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and hemicellulose of silages of corn, sorghum and Brachiaria brizantha. Three steers averaging 200kg bw were rumen fistulated. In each animal, the three silages were incubated for 0, 6, 12, 24, 36, 48, 72, and 96 hours. For the potential degradability and the effective degradability (passage rate 5 percent/h) the corn silage presented the highest values, 80.1 and 56.7 percent, respectively, followed by the sorghum silage (73.0 and 45.3 percent), and the Brachiaria silage (60.8 and 33.7 percent). For CP, the highest degradability value was also verified for the corn silage (87.0 percent), followed by the sorghum silage (81.8 percent), and Brachiaria silage (75.2 percent). For NDF, the highest degradability values were also verified for the corn and sorghum silages. However, for ADF, the sorghum silage presented degradation profile lower than the corn silage. The results suggest a better quality of the corn silage, followed by sorghum and Brachiaria silages.

Degradabilidade ruminal da matéria seca, da proteína bruta e da fração fibrosa de silagens de milho, de sorgo e de Brachiaria brizantha / Ruminal degradability of dry matter, crud protein, and fiber fraction of silages of corn, sorghum, and Brachiaria brizantha

Avaliou-se a degradação da matéria seca (MS), da proteína bruta (PB), da fibra em detergente neutro (FDN), da fibra em detergente ácido (FDA) e da hemicelulose das silagens de milho, de sorgo e de Brachiaria brizantha. Foram utilizados três novilhos Nelore, machos, fistulados no rúmen, com média de peso de 200kg. Em cada animal foram incubadas amostras das três silagens nos tempos de 0, 6, 12, 24, 36, 48, 72 e 96 horas. Para as degradabilidades potencial e efetiva da MS (taxa de passagem no rúmen de 5 por cento/h), a silagem de milho foi a que apresentou valores mais altos, 80,1 e 56,7 por cento, respectivamente, seguida da silagem de sorgo, 73,0 e 45,3 por cento, e da silagem de Brachiaria, 60,8 e 33,7 por cento. Para a PB, o maior valor de degradabilidade foi verificado para a silagem de milho, 87,0 por cento, seguida das silagens de sorgo, 81,8 por cento, e de Brachiaria, 75,2 por cento. A degradabilidade da FDN foi maior para as silagens de milho e sorgo. Para FDA, a silagem de sorgo apresentou perfil de degradação menor que a silagem de milho. Os resultados sugerem melhor qualidade da silagem de milho, seguida pela do sorgo e pela de Brachiaria.(AU)

The experiment evaluated the degradation of the dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and hemicellulose of silages of corn, sorghum and Brachiaria brizantha. Three steers averaging 200kg bw were rumen fistulated. In each animal, the three silages were incubated for 0, 6, 12, 24, 36, 48, 72, and 96 hours. For the potential degradability and the effective degradability (passage rate 5 percent/h) the corn silage presented the highest values, 80.1 and 56.7 percent, respectively, followed by the sorghum silage (73.0 and 45.3 percent), and the Brachiaria silage (60.8 and 33.7 percent). For CP, the highest degradability value was also verified for the corn silage (87.0 percent), followed by the sorghum silage (81.8 percent), and Brachiaria silage (75.2 percent). For NDF, the highest degradability values were also verified for the corn and sorghum silages. However, for ADF, the sorghum silage presented degradation profile lower than the corn silage. The results suggest a better quality of the corn silage, followed by sorghum and Brachiaria silages.(AU)

Pharmacological properties of a pore induced by raising intracellular Ca2+.

Recent studies on the P2X(7) receptor in 2BH4 cells and peritoneal macrophages have demonstrated that the raise in intracellular Ca(2+) concentration induces a pore opening similar to P2X(7) receptor pore. Herein, we have investigated whether the pore activated by the elevation of intracellular Ca(2+) concentration is associated to P2X(7) receptor. Using patch clamp in cell attached, whole cell configuration, and dye uptake, we measured the pore opening in cell types that express the P2X(7) receptor (2BH4 cells and peritoneal macrophages) and in cells that do not express this receptor (HEK-293 and IT45-RI cells). In 2BH4 cells, the stimulation with ionomycin (5-10 microM) increased intracellular free Ca(2+) concentration and induced pore formation with conductance of 421 +/- 14 pS, half-time (t(1/2)) for ethidium bromide uptake of 118 +/- 17 s, and t(1/2) for Lucifer yellow of 122 +/- 11 s. P2X(7) receptor antagonists did not block these effects. Stimulation of HEK-293 and IT45-RI cells resulted in pore formation with properties similar to those found for 2BH4 cells. Connexin hemichannel inhibitors (carbenoxolone and heptanol) also did not inhibit the pore-induced effect following the increase in intracellular Ca(2+) concentration. However, 5-(N,N-hexamethylene)-amiloride, a P2X(7) receptor pore blocker, inhibited the induced pore. Moreover, intracellular signaling modulators, such as calmodulin, phospholipase C, mitogen-activated protein kinase, and cytoskeleton components were important for the pore formation. Additionally, we confirmed the results obtained for electrophysiology by using the flow cytometry, and we discarded the possibility of cellular death induced by raising intracellular Ca(2+) at the doses used by using lactate dehydrogenase release assay. In conclusion, increased concentration in intracellular Ca(+2) induces a novel membrane pore pharmacologically different from the P2X(7) associated pore and hemigap-junction pore.

Trophic activity derived from bone marrow mononuclear cells increases peripheral nerve regeneration by acting on both neuronal and glial cell populations.

A rat model of complete sciatic nerve transection was used to evaluate the effect of bone marrow mononuclear cells (BMMC) transplanted to the injury site immediately after lesion. Rats treated with BMMC had both sensory and motor axons reaching the distal stump earlier compared to untreated animals. In addition, BMMC transplantation reduced cell death in dorsal root ganglia (DRG) compared to control animals. Transplanted BMMC remained in the lesion site for several days but there is no evidence of BMMC differentiation into Schwann cells. However, an increase in the number of Schwann cells, satellite cells and astrocytes was observed in the treated group. Moreover, neutralizing antibodies for nerve growth factor (NGF) (but not for brain-derived neurotrophic factor and ciliary-derived neurotrophic factor) added to the BMMC-conditioned medium reduced neurite growth of sensory and sympathetic neurons in vitro, suggesting that BMMC release NGF, improve regeneration of the sciatic nerve in the adult rat and stimulate Schwann and satellite cell proliferation or a combination of both.