Effects of area and isolation of woodland patches on herbaceous plant species richness across Great Britain   总被引：5，自引：2，他引：5  

Petit  Sandrine  Griffiths  Leila  Smart  Simon S.  Smith  Geoff M.  Stuart  Rick C.  Wright  Simon M. 《Landscape Ecology》2004,19(5):463-471

Richness of Ancient Woodland Indicator plant species was analysed in 308 woodland patches that were surveyed during the Countryside Survey of Great Britain carried out in 1998. The Countryside Survey recorded vegetation plots and landscape structure in 569 stratified 1 km sample squares and developed a remotely-sensed land cover map of the UK. Using these datasets, we tested the hypothesis that Ancient Woodland Indicator species richness in woodland fragments was limited by patch area, shape and spatial isolation and that woodland patches located in the lowland region of Great Britain would respond differently than those in the upland region. The variation in Ancient Woodland Indicator species richness in the British lowlands (n = 218) was mainly explained by patch area and two measures of connectivity, the length of hedgerows and lines of trees in the 1 km square and the area of woodland within 500 m of the vegetation plot. By contrast, variation in Ancient Woodland Indicator species richness in the British uplands (n = 90) was related to Ellenberg scores of the vegetation communities sampled – a surrogate for habitat quality – and no significant effect of spatial structure was detected. It therefore appears that the degree of fragmentation of woodland in the British lowlands limits the distribution of Ancient Woodland Indicator species, while in the uplands, failed colonisation is a matter of habitat quality rather than a result of landscape structure.This revised version was published online in May 2005 with corrections to the Cover Date.  相似文献   

Ontogeny of the digestive tract of Centropomus parallelus larvae     

Andressa Teles  Wanessa Melo Costa  Dib Ammar  Yara M. Rauh Müller  Evelise M. Nazari  Vinicius Ronzani Cerqueira 《Fish physiology and biochemistry》2015,41(2):549-559

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Brewery residues as a source of organic carbon in Litopenaeus schmitti white shrimp farms with BFT systems     

Michelle Midori Sena Fugimura  Helaine dos Reis Flor  Emanuela Paula de Melo  Tiago Viana da Costa  Wilson Wasielesky Jr.  Lidia Miyako Yoshii Oshiro 《Aquaculture International》2015,23(2):509-522

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Effects of gossypol from cottonseed cake on the blood profile in sheep     

Antônio Carlos Lopes Câmara  André Menezes do Vale  Cláudio Roberto Scabelo Mattoso  Marília Martins Melo  Benito Soto-Blanco 《Tropical animal health and production》2016,48(5):1037-1042

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Requirements of protein for maintenance and growth in ram hair lambs     

Elzania Sales Pereira  Rildson Melo Fontenele  Ariosvaldo Nunes de Medeiros  Ronaldo Lopes Oliveira  Ana Claudia Nascimento Campos  Eduardo Luiz Heinzen  Leilson Rocha Bezerra 《Tropical animal health and production》2016,48(7):1323-1327

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Intake,performance, and carcass characteristics of lambs fed spineless cactus replacing wheat bran     

Sabrina Carla Rodrigues Felix  Ricardo Alexandre Silva Pessoa  Marcelo de Andrade Ferreira  Luciana Felizardo Pereira Soares  Janaina de Lima Silva  Karen Santos Felix de Abreu  Ana Caroline Cerqueira de Melo 《Tropical animal health and production》2016,48(2):465-468

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Comparison of duplex PCR and microscopic techniques for the identification of Babesia bigemina and Babesia bovis in engorged female ticks of Boophilus microplus     

Quintão-Silva MG  Melo MN  Ribeiro MF 《Zoonoses and public health》2007,54(3-4):147-151

A single-step duplex polymerase chain reaction (PCR) technique and traditional microscopic examination of haemolymph smears were used to detect Babesia bigemina and/or Babesia bovis infection in engorged female ticks of Boophilus microplus recovered from calves raised in an endemic area of the State of Minas Gerais, Brazil. In the PCR amplification of tick-derived DNA, pairs of oligonucleotide primers specific for a 278-bp sequence from B. bigemina and for a 350-bp sequence from B. bovis were used conjointly. The microscopic examination of haemolymph revealed that 16.7% of the engorged ticks were infected with Babesia spp., although no significant differences (rho > 0.05) were found in the infection rate of ticks collected from calves of different age groups. PCR analysis showed that 77.8% of the engorged ticks whose haemolymph contained sporokinetes were infected with B. bigemina, 7.8% with B. bovis and 14.4% with both protozoan species. However, the PCR assay further revealed that, amongst the engorged female ticks whose haemolymph was apparently negative for the presence of sporokinetes, 15.6% were infected with B. bigemina, 2.2% with B. bovis and 10.0% with both species. The duplex PCR method is thus more efficient and sensitive than the microscopic assay and also permits facile identification of the protozoa species present in engorged female ticks.  相似文献   

Pronuclear Embryo Yield in Canindé and Saanen Goats for DNA Microinjection     

RR Moura  ES Lopes‐Junior  DIA Teixeira  IA Serova  LE Andreeva  LM Melo  VJF Freitas 《Reproduction in domestic animals》2010,45(5):e101-e106

The objective of this study was to examine the effect of donor breed on pronuclear‐stage embryo yield to be used for DNA microinjection in a transgenesis goat program. Twelve Canindé and twelve Saanen goats were heat synchronized using a progestagen‐cloprostenol treatment. Forty‐eight hours before the sponge removal, superovulation was induced with a total administration of 4.4 mg/kg bodyweight NIH‐FSH‐P1, given twice daily in decreasing doses over 3 days. In addition, goats received 100 μg of GnRH and they were hand‐mated at 36 and 48 h after progestagen removal. Embryo recovery was performed by oviduct flushing at 72 h after sponge removal. Embryos were microinjected with a DNA construct and noticeable swelling of the nuclei was the criterion for successful microinjection. The total diameter, cytoplasm diameter, zona pellucida thickness and pronuclei diameter were measured for each microinjected embryo. A higher (p < 0.05) percentage of fertilized ova was observed in Canindé (89.9%) than Saanen (36.2%) goats. In addition, Canindé donors produced a higher percentage of pronuclear embryos when compared with Saanen: 72.5% vs 20.6% (p < 0.05), respectively. Successful microinjection was verified in 96.7% and 73.3% of times in Canindé and Saanen embryos, respectively (p < 0.05). Significant differences were observed for all morphometric parameters except for cytoplasm diameter. In conclusion, under our study experimental conditions, Canindé were more efficient than Saanen goats concerning the pronuclear embryo yield and manipulation. The use of Canindé goats in transgenesis programs could be increase the interest in their breeding and could be contribute to saving them from extinction.  相似文献   

Ecosystem services from coffee agroforestry in Central America: estimation using the CAF2021 model     

van Oijen  Marcel  Haggar  Jeremy  Barrios  Mirna  Büchi  Lucie  Cerda  Rolando  Cerretelli  Stefania  López  Erick  de Melo Virginio Filho  Elias  Ospina  Alejandra 《Agroforestry Systems》2022,96(7):969-981

The goal of sustainable coffee production requires multiple functions from agroforestry systems. Many are difficult to quantify and data are lacking, hampering the choice of shade tree species and agronomic management. Process-based modelling may help quantify ecosystem services and disservices. We introduce and apply coffee agroforestry model CAF2021 (https://doi.org/10.5281/zenodo.5862195). The model allows for complex systems with up to three shade tree species. It simulates coffee yield, timber and fruit production by shade trees, soil loss in erosion, C-sequestration, N-fixation, -emission and -leaching. To calibrate the model, we used multivariate data from 32 different treatments applied in two long-term coffee agroforestry experiments in Costa Rica and Nicaragua. Without any further calibration, the model was then applied to agroforestry systems on 89 farms in Costa Rica and 79 in Guatemala where yields had been reported previously in farmer interviews. Despite wide variation in environmental and agronomic conditions, the model explained 36% of yield variation in Costa Rica but only 15% in Guatemala. Model analysis quantified trade-offs between yield and other ecosystem services as a function of fertilisation and shading.

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Cloning and characterization of gene-resistant analogs (RGAs) involved in rust (Puccinia psidii) resistance in Eucalyptus grandis     

Marcelo Luiz Laia  Acelino Couto Alfenas  Sergio Hermnio Brommonschenkel  Shinitiro Oda  Eduardo Jose de Melo  Inae Marie de Arau jo Silva  Janana Fernandes Goncalves  Ariadne Marques 《林业研究》2015,(3)

Disease-resistant genes play an important role in defending against a variety of pathogens and insect pests in plants. Most of the disease-resistant genes encode pro-teins with conserved leucine rich r...  相似文献