Agriculturally productive yet biodiverse: human benefits and conservation values along a forest-agriculture gradient in Southern Ethiopia     

Baudron  Frédéric  Schultner  Jannik  Duriaux  Jean-Yves  Gergel  Sarah E.  Sunderland  Terry 《Landscape Ecology》2019,34(2):341-356

Landscape Ecology - It remains unclear how agricultural landscapes can best serve multiple purposes such as simultaneously maintaining agricultural productivity and conserving biodiversity. Our...  相似文献   

Eco‐efficiency as a strategy for optimizing the sustainability of pest management     

Roger D Magarey  Sarah SH Klammer  Thomas M Chappell  Christina M Trexler  Godshen R Pallipparambil  Ernie F Hain 《Pest management science》2019,75(12):3129-3134

Agricultural industrialization and the subsequent reliance on pesticides has resulted in numerous unintended consequences, such as impacts upon the environment and by extension human health. Eco‐efficiency is a strategy for sustainably increasing production, while simultaneously decreasing these externalities on ecological systems. Eco‐efficiency is defined as the ratio of production to environmental impacts. It has been widely adopted to improve chemical production, but we investigate the challenges of applying eco‐efficiency to pesticide use. Eco‐efficiency strategies include technological innovation, investment in research and development, improvement of business processes, and accounting for market forces. These components are often part of integrated pest management (IPM) systems that include alternatives to pesticides, but its implementation is often thwarted by commercial realities and technical challenges. We propose the creation and adoption of an eco‐efficiency index for pesticide use so that the broad benefits of eco‐efficient strategies such as IPM can be more readily quantified. We propose an index based upon the ratio of crop yield to a risk quotient (RQ) calculated from pesticide toxicity. Eco‐efficiency is an operational basis for optimizing pest management for sustainability. It naturally favors adoption of IPM and should be considered by regulators, researchers, and practitioners involved in pest management. © 2019 Society of Chemical Industry  相似文献   

Optimizing aphid biocontrol with the predator Aphidoletes aphidimyza,based on biology and ecology     

Franois‐Xavier Boulanger  Sarah Jandricic  Karel Bolckmans  Felix L Wckers  Apostolos Pekas 《Pest management science》2019,75(6):1479-1493

Aphidoletes aphidimyza is one of the most important predators used in the augmentative biological control of aphids, key pests of many crops worldwide. Adult females are very efficient in locating aphid infestations over a relatively long range, up to 45 m, and deposit eggs near or within aphid colonies. The predatory larvae are aphid generalists preying on several agriculturally important aphid species. The successful use of this biocontrol agent in agricultural systems depends on several biotic and abiotic factors. Among biotic factors, aphid species, plant structure, interspecific competition and intraguild predation may significantly impact the predator´s population dynamics. Key abiotic conditions include day lengths (above a critical threshold to prevent diapause), availability of mating sites in the crop, temperature (above 15 °C to enable egg laying), air relative humidity (above 70%) and availability of pupation sites. Although several successes have been reported in open field crops with naturally occurring or released populations, commercial releases are primarily used in protected crops. Optimized emergence boxes combining provisioning of food sources for the adults, integration with the technological advances that occurred in the greenhouse environment lately, insights into the nutritional ecology in open field crops and exploration of the genetic variability are proposed as future directions to improve adoption and efficacy of A. aphidimyza in crop protection. © 2018 Society of Chemical Industry  相似文献   

Computed tomography of testicular torsion in a juvenile dog with unilateral cryptorchidism     

Sarah A. Slaughter  Andrew D. Eitzer  Sara E. Tolliver  Sarah N. Holman  Sara A. Colopy  Seamus E. Hoey  Samantha J. Loeber 《The Canadian veterinary journal. La revue veterinaire canadienne》2022,63(5):515

A 14-week-old male unilaterally cryptorchid Clumber spaniel was presented for acute lethargy. Physical examination revealed abdominal pain, and a single testis was palpated in the scrotum. Abdominal ultrasound and computed tomography (CT) revealed a poorly vascularized, ovoid structure immediately caudal to the left kidney with scant regional peritoneal effusion. Left intra-abdominal testicular torsion was confirmed at surgery, and routine cryptorchidectomy was performed. The patient recovered uneventfully from anesthesia and surgery.Key clinical message:The most common CT characteristics of testicular torsion were present in this case and correlated well with sonographic findings to allow for rapid, accurate diagnosis and surgical planning of unilateral, non-neoplastic, intra-abdominal cryptorchid testicular torsion in a juvenile dog. Contrast enhanced CT facilitated accurate localization of the undescended testis and evaluation of testicular perfusion and may be a useful alternative to ultrasound for diagnosing testicular torsion, especially in indeterminate cases.  相似文献   

Seasonal speedup along the western flank of the Greenland Ice Sheet   总被引：1，自引：0，他引：1  

Joughin I  Das SB  King MA  Smith BE  Howat IM  Moon T 《Science (New York, N.Y.)》2008,320(5877):781-783

It has been widely hypothesized that a warmer climate in Greenland would increase the volume of lubricating surface meltwater reaching the ice-bedrock interface, accelerating ice flow and increasing mass loss. We have assembled a data set that provides a synoptic-scale view, spanning ice-sheet to outlet-glacier flow, with which to evaluate this hypothesis. On the ice sheet, these data reveal summer speedups (50 to 100%) consistent with, but somewhat larger than, earlier observations. The relative speedup of outlet glaciers, however, is far smaller (<15%). Furthermore, the dominant seasonal influence on Jakobshavn Isbrae's flow is the calving front's annual advance and retreat. With other effects producing outlet-glacier speedups an order of magnitude larger, seasonal melt's influence on ice flow is likely confined to those regions dominated by ice-sheet flow.  相似文献   

Henneguya curvata sp. n. (Myxosporea: Myxobolidae) parasitizing the gills of Serrasalmus spilopleura (Characidae: Serrasalminae), a South American freshwater fish     

Barassa B  Adriano EA  Arana S  Cordeiro NS 《Folia parasitologica》2003,50(2):151-153

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Diagnosis of trichomoniasis in 'virgin' bulls by culture and polymerase chain reaction          下载免费PDF全文

Parker S  Campbell J  McIntosh K  Gajadhar A 《The Canadian veterinary journal. La revue veterinaire canadienne》2003,44(9):732-734

The diagnostic test for Tritrichomonas foetus in bulls is microscopic examination of cultured preputial samples. Trichomonads other than T. foetus can be present in a preputial sample. Both a staining technique and a polymerase chain reaction assay were useful in differentiating between T. foetus and another trichomonad observed in samples from virgin bulls.  相似文献   

Vaccination against foot-and-mouth disease: the implications for Canada          下载免费PDF全文

Kahn S  Geale DW  Kitching PR  Bouffard A  Allard DG  Duncan JR 《The Canadian veterinary journal. La revue veterinaire canadienne》2002,43(5):349-354

Vaccination of susceptible animals against foot-and-mouth disease (FMD) is a well established strategy for helping to combat the disease. Traditionally, FMD vaccine has been used to control a disease incursion in countries where the disease has been endemic rather than in countries considered free of the disease. In 2001, the use of vaccine was considered but not implemented in the United Kingdom (1), whereas vaccine was used to help to control FMD in The Netherlands (2,3). Canadian contingency plans provide for the use of vaccine; Canada is a member of the North American Foot-and-Mouth Disease Vaccine Bank, which could supply vaccine if needed. This article explains why Canada might use FMD vaccine to combat an outbreak and the factors that are relevant to the disposal of vaccinated animals and their products. It concludes that vaccination is an important mechanism in Canada's preparedness for an outbreak of FMD and that products from vaccinated animals are safe for human consumption.  相似文献   

Eosinophilic gastroenteritis in a dog          下载免费PDF全文

McTavish S 《The Canadian veterinary journal. La revue veterinaire canadienne》2002,43(6):463-465

A 9-year-old mixed-breed dog was evaluated for chronic intermittent vomiting, hematemesis, and melena lasting several months. Biopsy specimens obtained during exploratory laparotomy revealed eosinophilic gastroenteritis. Treatment included drug therapy to reduce gastrointestinal inflammation and dietary management to limit antigenic exposure.  相似文献   

The Occurrence of dsRNA Species in Apparently Healthy and Virus-infected Ribes Cultivars, and Evidence That One Such Species Originates from a Member of the Virus Family Totiviridae     

Sarah Cox  M.A. Mayo  A. Teifion Jones 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(4):353-364

Analysis was made of dsRNA in 37 cultivars and species of Ribes, that were healthy, naturally affected with the virus-like diseases, blackcurrant yellows, blackcurrant infectious variegation, gooseberry veinbanding or blackcurrant reversion, or graft-inoculated with scions from such diseased plants. Various dsRNA species, differing in size (from ca. 2 to 11kbp), number and staining intensity in gels, were detected in some or all assays of all plants, including those held as virus-tested stock. In different plant tissues from individual plants, the dsRNA species were usually similar in size and number but, in some sources, the dsRNA profile from flowers and/or bark differed greatly from the profiles of dsRNA obtained from leaves. No dsRNA species were associated consistently with any of these diseases. A 499kbp cDNA probe was obtained that in Northern blot analysis was specific to a ca. 5kbp dsRNA species present in the blackcurrant cv. Baldwin. It also detected a similarly sized dsRNA species in plants of many other blackcurrant cultivars, but it did not react with a similarly sized dsRNA species in redcurrant and gooseberry tissues. The 156 amino acid sequence encoded by the cDNA was very similar to sequences in the RNA-directed RNA polymerases of virus species in the family Totiviridae, especially Saccharomyces cerevisiae viruses L-1 and L-A. The significance of these findings and the possible origin of these dsRNA species are discussed.  相似文献