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31.
Organogenesis and foetal haemodynamics during the normal gestation of healthy black‐rumped agoutis (Dasyprocta prymnolopha,Wagler, 1831) bred in captivity 下载免费PDF全文
FCA Sousa GT Pessoa LS Moura JR Araújo RPS Rodrigues MAPS Barbosa AN Diniz AB Souza EG Silva LU Lucena MP Sanches OF Silva‐Filho PC Guerra JM Sousa WC Neves FR Alves 《Reproduction in domestic animals》2017,52(1):60-66
The objective of this study was to define the patterns of organogenesis and foetal haemodynamics during the normal gestation of healthy agoutis (Dasyprocta prymnolopha) kept in captivity. Thirty pregnant agoutis that ranged in size from small to medium and weighed between 2.5 and 3 kg underwent B‐mode and Doppler ultrasonography for the biometric evaluation of the foetal organs. The foetal aortic blood flow proved to be predominantly systolic, and the measured flow velocity was 78.89 ± 2.95 cm/s, with a maximum pressure gradient of 2.12 ± 0.27 mmHg. The liver was characterized by its large volume, occupying the entire cranial aspect of the abdominal cavity, and it was associated cranially with the diaphragm and caudally with the stomach. The flow velocity in the portal vein was estimated to equal 12.17 ± 2.37 cm/s, with a resistivity index of 0.82 ± 0.05. The gallbladder was centrally located and protruded cranially towards the diaphragm. The spleen was visualized as an elongated structure with tapered cranial and caudal extremities, and the foetal kidneys were visualized bilaterally in the retroperitoneal region, with the right kidney positioned slightly more cranially than the left. The morphological characterization and hemodynamic analysis of the foetal organs of black‐rumped agoutis via B‐mode and Doppler ultrasonography allow determination of the vascular network and of reference values for the blood flow required for perfusing the anatomical elements essential for maintaining the viability of foetuses at different gestational ages. 相似文献
32.
T. D. Procter D. L. Pearl R. L. Finley E. K. Leonard N. Janecko R. J. Reid‐Smith J. S. Weese A. S. Peregrine J. M. Sargeant 《Zoonoses and public health》2014,61(3):208-218
An estimated 6 million pet dogs live in Canadian households with the potential to transmit zoonotic pathogens to humans. Dogs have been identified as carriers of Salmonella, Giardia and Campylobacter spp., particularly Campylobacter upsaliensis, but little is known about the prevalence and risk factors for these pathogens in pet dogs that visit dog parks. This study examined the prevalence of these organisms in the faeces of dogs visiting dog parks in three cities in south‐western Ontario, as well as risk factors for shedding Campylobacter spp. and C. upsaliensis. From May to August 2009, canine faecal samples were collected at ten dog parks in the cities of Guelph and Kitchener‐Waterloo, Ontario, Canada. Owners were asked to complete a questionnaire related to pet characteristics and management factors including age, diet and activities in which the dog participates. Faecal samples were collected from 251 dogs, and 189 questionnaires were completed. Salmonella, Giardia and Campylobacter spp. were present in 1.2%, 6.4% and 43.0% of faecal samples, respectively. Of the Campylobacter spp. detected, 86.1% were C. upsaliensis, 13% were C. jejuni and 0.9% were C. coli. Statistically significant sparing factors associated with the shedding of Campylobacter spp. included the feeding of a commercial dry diet and the dog's exposure to compost. Age of dog had a quadratic effect, with young dogs and senior dogs having an increased probability of shedding Campylobacter spp. compared with adult dogs. The only statistically significant risk factor for shedding C. upsaliensis was outdoor water access including lakes and ditches, while dogs >1 year old were at a lower risk than young dogs. Understanding the pet‐related risk factors for Campylobacter spp. and C. upsaliensis shedding in dogs may help in the development of awareness and management strategies to potentially reduce the risk of transmitting this pathogen from dogs to humans. 相似文献
33.
Variation of pathotypes and races and their correlations with clonal lineages in Verticillium dahliae 下载免费PDF全文
R. M. Jiménez‐Díaz C. Olivares‐García J. L. Trapero‐Casas M. M. Jiménez‐Gasco J. A. Navas‐Cortés B. B. Landa M. G. Milgroom 《Plant pathology》2017,66(4):651-666
Understanding pathogenic variation in plant pathogen populations is key for the development and use of host resistance for managing verticillium wilt diseases. A highly virulent defoliating (D) pathotype in Verticillium dahliae has previously been shown to occur only in one clonal lineage (lineage 1A). By contrast, no clear association has yet been shown for race 1 with clonal lineages. Race 1 carries the effector gene Ave1 and is avirulent on hosts that carry resistance gene Ve1 or its homologues. The hypothesis tested was that race 1 arose once in a single clonal lineage, which might be expected if V. dahliae acquired Ave1 by horizontal gene transfer from plants, as hypothesized previously. In a diverse sample of 195 V. dahliae isolates from nine clonal lineages, all race 1 isolates were present only in lineage 2A. Conversely, all lineage 2A isolates displayed the race 1 phenotype. Moreover, 900‐bp nucleotide sequences from Ave1 were identical among 27 lineage 2A isolates and identical to sequences from other V. dahliae race 1 isolates in GenBank. The finding of race 1 in a single clonal lineage, with identical Ave1 sequences, is consistent with the hypothesis that race 1 arose once in V. dahliae. Molecular markers and virulence assays also confirmed the well‐established finding that the D pathotype is found only in lineage 1A. Pathogenicity assays indicated that cotton and olive isolates of the D pathotype (lineage 1A) were highly virulent on cotton and olive, but had low virulence on tomato. 相似文献
34.
L. Hallau M. Neumann B. Klatt B. Kleinhenz T. Klein C. Kuhn M. Röhrig C. Bauckhage K. Kersting A.‐K. Mahlein U. Steiner E.‐C. Oerke 《Plant pathology》2018,67(2):399-410
Cercospora leaf spot (CLS) poses a high economic risk to sugar beet production due to its potential to greatly reduce yield and quality. For successful integrated management of CLS, rapid and accurate identification of the disease is essential. Diagnosis on the basis of typical visual symptoms is often compromised by the inability to differentiate CLS symptoms from similar symptoms caused by other foliar pathogens of varying significance, or from abiotic stress. An automated detection and classification of CLS and other leaf diseases, enabling a reliable basis for decisions in disease control, would be an alternative to visual as well as molecular and serological methods. This paper presents an algorithm based on a RGB‐image database captured with smartphone cameras for the identification of sugar beet leaf diseases. This tool combines image acquisition and segmentation on the smartphone and advanced image data processing on a server, based on texture features using colour, intensity and gradient values. The diseases are classified using a support vector machine with radial basis function kernel. The algorithm is suitable for binary‐class and multi‐class classification approaches, i.e. the separation between diseased and non‐diseased, and the differentiation among leaf diseases and non‐infected tissue. The classification accuracy for the differentiation of CLS, ramularia leaf spot, phoma leaf spot, beet rust and bacterial blight was 82%, better than that of sugar beet experts classifying diseases from images. However, the technology has not been tested by practitioners. This tool can be adapted to other crops and their diseases and may contribute to improved decision‐making in integrated disease control. 相似文献
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Interaction of chlorhexidine with trisEDTA or miconazole in vitro against canine meticillin‐resistant and ‐susceptible Staphylococcus pseudintermedius isolates from two UK regions 下载免费PDF全文
38.
Elieser S. Posner Ana A. Chew‐Guevara Marcelo Mitre‐Dieste Esther Perez‐Carrillo Erick Heredia‐Olea Jeff D. Wilson Sergio O. Serna‐Saldivar 《Cereal Chemistry》2014,91(2):139-145
Refined wheat flours commercially produced by five different U.S. and Mexican wheat blends intended for tortilla production were tested for quality and then processed into tortillas through the hot‐press forming procedure. Tortilla‐making qualities of the flour samples were evaluated during dough handling, hot pressing, baking, and the first five days on the shelf at room temperature. The predominant variables that affected the flour tortilla performance were wet gluten content, alveograph W (220–303) and P/L (0.70–0.94) parameters, farinograph water absorption (57%) and stability (10.8–18.7 min), starch damage (5.43–6.71%), and size distribution curves (uniform particle distribution). Flours produced from a blend of Dark Northern Spring (80%) and Mexican Rayon (20%) wheat had the highest water absorption, and tortillas obtained from this blend showed the highest diameter and lowest thickness. The whitest and best textured tortillas were obtained from the flour milled from three hard types of Mexican wheat blend. A Mixolab profile was generated from the best tortilla flours, those produced by mills 3 and 4. The Mixolab profile showed that a good flour for hot‐press tortillas had a relatively lower absorption and short dough mix time compared with a bread flour and should have a significantly higher gluten compared with an all‐purpose flour. Compared with bread flour, the tortilla flour had higher retrogradation and viscosity values. The Mixolab profile proved to be a good preliminary test to evaluate flours for hot‐press tortillas. 相似文献
39.
Ana T. Silva Martyn C. Lucas Theodore Castro‐Santos Christos Katopodis Lee J. Baumgartner Jason D. Thiem Kim Aarestrup Paulo S. Pompeu Gordon C. O'Brien Douglas C. Braun Nicholas J. Burnett David Z. Zhu Hans‐Petter Fjeldstad Torbjørn Forseth Nallamuthu Rajaratnam John G. Williams Steven J. Cooke 《Fish and Fisheries》2018,19(2):340-362
Much effort has been devoted to developing, constructing and refining fish passage facilities to enable target species to pass barriers on fluvial systems, and yet, fishway science, engineering and practice remain imperfect. In this review, 17 experts from different fish passage research fields (i.e., biology, ecology, physiology, ecohydraulics, engineering) and from different continents (i.e., North and South America, Europe, Africa, Australia) identified knowledge gaps and provided a roadmap for research priorities and technical developments. Once dominated by an engineering‐focused approach, fishway science today involves a wide range of disciplines from fish behaviour to socioeconomics to complex modelling of passage prioritization options in river networks. River barrier impacts on fish migration and dispersal are currently better understood than historically, but basic ecological knowledge underpinning the need for effective fish passage in many regions of the world, including in biodiversity hotspots (e.g., equatorial Africa, South‐East Asia), remains largely unknown. Designing efficient fishways, with minimal passage delay and post‐passage impacts, requires adaptive management and continued innovation. While the use of fishways in river restoration demands a transition towards fish passage at the community scale, advances in selective fishways are also needed to manage invasive fish colonization. Because of the erroneous view in some literature and communities of practice that fish passage is largely a proven technology, improved international collaboration, information sharing, method standardization and multidisciplinary training are needed. Further development of regional expertise is needed in South America, Asia and Africa where hydropower dams are currently being planned and constructed. 相似文献
40.
Double‐null partial waxy wheat (Triticum aestivum L.) flours were used for isolation of starch and preparation of white salted noodles and pan bread. Starch characteristics, textural properties of cooked noodles, and staling properties of bread during storage were determined and compared with those of wheat flours with regular amylose content. Starches isolated from double‐null partial waxy wheat flours contained 15.4–18.9% amylose and exhibited higher peak viscosity than starches of single‐null partial waxy and regular wheat flours, which contained 22.7–25.8% amylose. Despite higher protein content, double‐null partial waxy wheat flours, produced softer, more cohesive and less adhesive noodles than soft white wheat flours. With incorporation of partial waxy prime starches, noodles produced from reconstituted soft white wheat flours became softer, less adhesive, and more cohesive, indicating that partial waxy starches of low amylose content are responsible for the improvement of cooked white salted noodle texture. Partial waxy wheat flours with >15.1% protein produced bread of larger loaf volume and softer bread crumb even after storage than did the hard red spring wheat flour of 15.3% protein. Regardless of whether malt was used, bread baked from double‐null partial waxy wheat flours exhibited a slower firming rate during storage than bread baked from HRS wheat flour. 相似文献