20 research outputs found
Progress in Identifying High Nature Value Montados: Impacts of Grazing on Hardwood Rangeland Biodiversity
Due to their complex structure and traditional low-intensity management, Portuguese oak woodland rangelands
known as montados are often considered high nature value (HNV) farming systems, and as such, they may be deemed eligible for subsidies and incentives by governmental and nongovernmental agencies. Too little is
known about how the HNV concept might be applied to conserve complex silvopastoral systems. These systems, due to their structural and functional complexity at multiple scales, tend to support high levels of biodiversity. Montados are in sharp decline as a result of the rapid specialization of land management that, through simplification, undermines multifunctionality. Understanding how changes in management influence these systems and their biodiversity is needed for prioritizing conservation efforts and for ensuring they remain HNV systems. On
the basis of a field survey in 58 plots distributed among 29 paddocks on 17 farms, we conducted an integrated analysis of the relationship between grazing intensity and biodiversity in montados of similar biophysical and structural characteristics. Data on management were obtained through interviews, and biodiversity data (vegetation, macrofungi, birds, herpetofauna) were obtained through specific field protocols. Additional spatial data,
such as soil characteristics, slope, land cover, and linear landscape elements, were also analyzed. The results show no overall biodiversity variation as a result of different management practices. However, different groups of species react differently to specific management practices, and within a pasture, grazing impacts are heterogenous. In low grazing intensity plots, macrofungi species richness was found to be higher, while bird species richness was lower. Using tree regeneration as proxy for montado sustainability, results show less tree regeneration
in areas with higher forage quality and more intense grazing. Pathways for future progress are proposed, including creating areas within a paddock that attract grazing away from where regeneration is desired
Progress in Identifying High Nature Value Montados: Impacts of Grazing on Hardwood Rangeland Biodiversity
Due to their complex structure and traditional low-intensity management, Portuguese oak woodland rangelands
known as montados are often considered high nature value (HNV) farming systems, and as such, they may be
deemed eligible for subsidies and incentives by governmental and nongovernmental agencies. Too little is
known about how the HNV concept might be applied to conserve complex silvopastoral systems. These systems,
due to their structural and functional complexity at multiple scales, tend to support high levels of biodiversity.
Montados are in sharp decline as a result of the rapid specialization of land management that, through simplification, undermines multifunctionality. Understanding how changes in management influence these systems and
their biodiversity is needed for prioritizing conservation efforts and for ensuring they remain HNV systems. On
the basis of a field survey in 58 plots distributed among 29 paddocks on 17 farms, we conducted an integrated
analysis of the relationship between grazing intensity and biodiversity in montados of similar biophysical and
structural characteristics. Data on management were obtained through interviews, and biodiversity data (vegetation, macrofungi, birds, herpetofauna) were obtained through specific field protocols. Additional spatial data,
such as soil characteristics, slope, land cover, and linear landscape elements, were also analyzed. The results
show no overall biodiversity variation as a result of different management practices. However, different groups
of species react differently to specific management practices, and within a pasture, grazing impacts are heterogenous. In low grazing intensity plots, macrofungi species richness was found to be higher, while bird species richness was lower. Using tree regeneration as proxy for montado sustainability, results show less tree regeneration
in areas with higher forage quality and more intense grazing. Pathways for future progress are proposed, including creating areas within a paddock that attract grazing away from where regeneration is desired
Progress in analytical approaches integrating Livestock and Biodiversity to identify HNV Montados
The World Congress Silvo-Pastoral Systems 2016 aims to gather researchers from different disciplines, practitioners and policy makers at different governance levels that deal with the management and sustainability of silvo-pastoral systems. In this way the congress will create a fertile context to progress through interdisciplinarity research approaches that can help translate scientific knowledge into new adaptive management solutions, and thus bridge from science to practice. The aim is also to gather and compare knowledge from silvo-pastoral systems around the world, which share drought as a limiting factor, so that they can be discussed and evaluated
Livro Verde dos Montados
O Livro Verde dos Montados apresenta diversos objectivos que se interligam:
Em primeiro lugar, o Livro Verde pretende reunir e sistematizar, de uma forma simples e acessível ao público, o conhecimento produzido em Portugal pelos investigadores e técnicos de várias instituições de investigação ou de gestão que estudam o Montado. Assume-se como uma oportunidade de caracterizar o sistema tendo em conta as suas várias dimensões, identificando as principais ameaças à sua preservação assim como os caminhos que podem ajudar à sua sustentabilidade. Não sendo um documento científico, baseia-se no conhecimento científico e pretende constituir a base para uma plataforma de organização, tanto dos investigadores como do conhecimento científico actualmente produzido em Portugal sobre o Montado.Em segundo lugar, o Livro Verde deverá contribuir para um entendimento partilhado do que é o Montado, por parte do público, de técnicos e de especialistas, conduzindo a uma classificação mais clara do que pode ser considerado Montado e de quais os tipos distintos de Montados que podem ser identificados.
Em terceiro lugar, o Livro Verde estabelece as bases para uma estratégia coordenada de disponibilização de informação sobre o sistema Montado, visando o seu conhecimento, apreciação e valorização pela sociedade portuguesa no seu conjunto. Deste modo, o Livro Verde poderá constituir um instrumento congregador e inspirador para a realização de acções de sensibilização e informação sobre o Montado.
Em quarto lugar, pretende-se que o Livro Verde contribua para um maior reconhecimento e valorização do Montado como sistema, a nível do desenho das políticas nacionais por parte dos vários sectores envolvidos.Finalmente, o Livro Verde constituirá um documento parceiro do Livro Verde das Dehesas, produzido em Espanha em 2010, de forma a reforçar o reconhecimento e a devida valorização destes sistemas silvo-pastoris no desenho das estratégias e políticas relevantes pelas instituições europeias.
Em suma, os autores pretendem que o Livro Verde dos Montados se afirme como o primeiro passo para uma efectiva definição e implementação de uma estratégia nacional para os Montados
Efeitos da aplicação de prostaglandinas intervaladas de 10 dias sobre características reprodutivas de cabras leiteiras nulíparas cíclicas
Relataram-se os efeitos da aplicação de prostaglandina sobre características reprodutivas de cabras leiteiras nulíparas cíclicas. Cabras Alpinas (n=9) e Saanen (n=9) receberam duas doses de 22,5mg PGF2a com 10 dias de intervalo. A progesterona plasmática (ng/mL) foi determinada a partir de amostras de sangue coletadas nos dias 0 (primeira dose), 5, 10 (segunda dose), 15, 20, 25 e 30. Após início do segundo estro, as fêmeas foram monitoradas por ultrassonografia transretal a cada quatro horas até oito horas após a ovulação. A gestação foi verificada por ultrassonografia transretal nos dias 20, 25, 30, 35 e 90 após a segunda dose. As características estudadas foram semelhantes entre as raças (P>0,05). Animais em estro e o intervalo parto-estro de, respectivamente, 78,9% e 50,6±17,2h e 88,9% e 50,0±14,8h após a primeira e segunda administrações de prostaglandina, não diferiram (P>0,05). Todas as cabras ovularam e registraram-se valores do intervalo parto-ovulação após a segunda aplicação de prostaglandina de 64,5±19,5h e após início do estro de 18,0±9,1h, a taxa de ovulação de 1,3±0,5 e diâmetro do folículo ovulatório de 8,1±1,1mm. Perda embrionária ocorreu antes de 30 dias de gestação. O estro pode ser eficientemente sincronizado em cabras leiteiras núliparas com duas doses de prostaglandina intervaladas de 10 dias. _________________________________________________________________________________________ ABSTRACT: This study reported the effects of prostaglandin (PGF2a) administration 10 days apart on reproductive parameters of cyclic artificial inseminated (AI) nulliparous Alpine (n=9) and Saanen (n=9) goats. Animals received two doses of 22.5mg PGF2a 10 days apart. After 1st and 2nd PGF2a administrations, estrus was monitored at 12 h intervals, with a buck teaser. Plasma progesterone concentration (ng/mL) was determined from blood sampled on day 0 (1st PGF2a) and the following 5, 10 (2nd PGF2a), 15, 20, 25 and 30 days. After the onset of the second estrus, females were transrectally (5 MHz probe) scanned at 4 hour intervals until at least 8h after ovulation. Pregnancy was checked through transrectal ultrasound on days 20, 25, 30, 35 and 90 after insemination. All parameters studied did not differ between breeds (P>0.05). Estrous response and interval to estrus, respectively, after 1st (78.9% and 50.6±17.2h) and 2nd PGF2a (88.9% and 50.0±14.8h) administration did not differ (P>0.05). Overall animals ovulating (100.0%), interval to ovulation after 2nd PGF2a (64.5±19.5h) and after estrous onset (18.0±9.1h), ovulation rate (1.3±0.5), diameter of ovulatory follicle (8.1±1.1mm) were recorded. Embryo loss occurred before day 30 of pregnancy. Estrus can be efficiently synchronized in nulliparous Alpine and Saanen goats with two doses of prostaglandin 10 days apart
Effect Of Ropivacaine Combined With Pancuronium On Neuromuscular Transmission And Effectiveness Of Neostigmine And 4-aminopyridine For Blockade Reversal: Experimental Study [efeito Da Associação Ropivacaina-pancurÔnio Na Transmissão Neuromuscular E Eficácia Da Neostigmine E 4-aminopiridina Na Reversão Do Bloqueio: Estudo Experimental]
Background and objectives: The local anesthetic effects on neuromuscular junction and its influence on blockade produced by nondepolarizing neuromuscular blockers are still under-investigated; however, this interaction has been described in experimental studies and in humans. The aim of this study was to evaluate in vitro the interaction between ropivacaine and pancuronium, the influence on transmission and neuromuscular blockade, and the effectiveness of neostigmine and 4-aminopyridine to reverse the blockade. Methods: Rats were divided into groups (n=5) according to the study drug: ropivacaine (5μgmL-1); pancuronium (2μg.mL-1); ropivacaine+pancuronium. Neostigmine and 4-aminopyridine were used at concentrations of 2μgmL-1 and 20μgmL-1, respectively. The effects of ropivacaine on membrane potential and miniature end-plate potential, the amplitude of diaphragm responses before and 60minutes after the addition of ropivacaine (degree of neuromuscular blockade with pancuronium and with the association of pancuronium-ropivacaine), and the effectiveness of neostigmine and 4-aminopyridine on neuromuscular block reversal were evaluated. Results: Ropivacaine did not alter the amplitude of muscle response (the membrane potential), but decreased the frequency and amplitude of the miniature end-plate potential. Pancuronium blockade was potentiated by ropivacaine, and partially and fully reversed by neostigmine and 4-aminopyridine, respectively. Conclusions: Ropivacaine increased the neuromuscular block produced by pancuronium. The complete antagonism with 4-aminopyridine suggests presynaptic action of ropivacaine.652136140Toft, P., Kirkegaard Nielsen, H., Severinsen, I., Effect of epidurally administered bupivacaine on atracurium-induced neuromuscular blockade (1990) Acta Anaesthesiol Scand, 34, pp. 649-652Taivainen, T., Meretoja, O.A., Rosenberg, P.H., The effect of epidural bupivacaine on vecuronium-induced neuromuscular blockade in children (1994) Acta Anesthesiol Scand, 38, pp. 453-456Suzuki, T., Mizutani, H., Ishikawa, K., Epidurally administered mepivacaine delays recovery of train-of-four ratio from vecuronium-induced neuromuscular block (2007) Br J Anaesth, 99, pp. 721-725Sahin, S.H., Colak, A., Sezer, A., Effect of epidural levobupivacaine on recovery from vecuronium-induced neuromuscular block in patients undergoing lower abdominal surgery (2011) Anaesth Intensive Care, 39, pp. 607-610Loyola, Y.C., Braga Ade, F., Potério, G.M., Influence of lidocaine on the neuromuscular block produced by rocuronium: study in rat phrenic-diaphragmatic nerve preparation (2006) Rev Bras Anestesiol, 56, pp. 147-156Braga, A.F., Carvalho, V.H., Braga, F.S., Influence of local anesthetics on the neuromuscular blockade produced by rocuronium: effects of lidocaine and 50% enantiomeric excess bupivacaine on the neuromuscular junction (2009) Rev Bras Anestesiol, 59, pp. 725-734Carvalho, V.H., Braga, A.F., Braga, F.S., The influence of lidocaine and racemic bupivacaine on neuromuscular blockade produced by rocuronium. A study in rat phrenic nerve-diaphragm preparation (2009) Acta Cir Bras, 24, pp. 211-215Covino, B.G., Pharmacology of local anaesthetic agents (1986) Br J Anaesth, 58, pp. 701-716McLure, H.A., Rubin, A.P., Review of local anaesthetic agents (2005) Minerva Anestesiol, 71, pp. 59-74Stoelting, R.K., Hillier, S.C., Neuromuscular blocking drugs (2006) Pharmacology & Phisiology in Anesthetic Practice., pp. 208-250. , Lippincott Williams & Wilk, Philadelphia, R.K. Stoelting, S.C. Hillier (Eds.)Bulbring, E., Observation on the isolated phrenic nerve-diaphragm preparation of the rat (1946) Br J Pharmacol, 1, pp. 38-61Cardoso, L.S.M., Martins, C.R., Tardelli, M.A., Efeitos da lidocaína por via venosa sobre a farmacodinâmica do rocurÔnio (2005) Rev Bras Anestesiol, 55, pp. 371-380Matsuo, S., Rao, D.B., Chaudry, I., Interaction of muscle relaxants and local anesthetics at the neuromuscular junction (1978) Anesth Analg, 57, pp. 580-587Barash, P.G., Cullen, B.F., Stoelting, R.K., Anesthetic agents, adjuvants, and drug interaction (2009) Clinical Anesthesia, pp. 514-515. , Lippincot Williams & Wilkins Kluwer Business, Philadelphia, P.G. Barash (Ed.)Carpenter, R.L., Mulroy, M.F., Edrophonium antagonize combined lidocaine-pacuronium and verapamil-pancuronium neuromuscular blockade in cats (1986) Anesthesiology, 65, pp. 506-510Neher, E., Steinbach, J.H., Local anesthetics transiently block currents through single acetylcholine-receptor channels (1978) J Physiol, 277, pp. 153-176Pederneiras, S.G., Interação de drogas com relaxantes musculares (1988) Rev Bras Anestesiol, 38, pp. 63-73Suzuki, T., Nagai, H., Katsumata, N., Investigation of fading responses induced by non-depolarising muscle relaxants in the evoked EMG of the gastrocnemius muscle of the cat (1999) Acta Anaesthesiol Scand, 43, pp. 658-662Usubiaga, J.E., Wikinski, J.A., Morales, R.L., Interaction of intravenously administered procaine, lidocaine and succinylcholine in anesthetized subjects (1967) Anesth Analg, 46, pp. 39-45Ellis, C.H., Wnuck, A.L., De Beer, E.J., Modifying actions of procaine on the myoneural blocking actions of succinylcholine, decamethonium and d-tubocurarine in dogs and cats (1953) Am J Physiol, 174, pp. 277-282Ulbricht, W., Wagner, H.H., Block of potassium channels of the nodal membrane by 4-aminopyridine and its partial removal on depolarization (1976) Pflugers Arch, 367, pp. 77-87Harvey, A.L., Marshall, I.G., The facilitatory actions of aminopyridines and tetraethylammonium on neuromuscular transmission and muscle contractility in avian muscle (1977) Naunyn Schmiedebergs Arch Pharmacol, 299, pp. 53-60Harvey, A.L., Marshall, I.G., The actions of three diaminopyridines on the chick biventer cervicis muscle (1977) Eur J Pharmacol, 44, pp. 303-30