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1.
Comparative survival and growth performance of European lobster larvae,Homarus gammarus,reared on dry feed and conspecifics 下载免费PDF全文
Adam Powell James Hinchcliffe Kristina Sundell Nils‐Gunnar Carlsson Susanne P. Eriksson 《Aquaculture Research》2017,48(10):5300-5310
A bottleneck of crustacean larval culture concerns nutrition and associated cannibalism in communal rearing systems, which impact on larval survival, development and growth. For early‐stage European lobster, Homarus gammarus larvae, feeding ecology and body composition are largely unknown. We initiated four progressive feeding experiments (novel feed types, feeding regime and feed size and cannibalism effects) on growth and survival, to inform and update husbandry protocols. Performance of larvae offered a dry commercial feed was not significantly different compared with a conventional wet plankton feed of the same ration and size grade (both within 600–1,000 μm). Further experiments found that the same ration of dry feed offered six times daily improved development and growth, over the conventional regime of three times daily. Small‐grade dry feed (particles: 250–360 μm) improved larval performance compared with a larger feed (360–650 μm). Larvae were also fed different proportions of dry feed and/or conspecifics in both communal and individual rearing systems (the latter preventing cannibalism via segregation). Individually reared larvae, fed only dead conspecifics, displayed the greatest survival (80%) to postlarvae. This underlines the impact of cannibalism on survival and nutrition in H. gammarus larviculture. A final experiment analysed H. gammarus zoea 1 composition, identifying deficiencies in ash and carbohydrate in lobster feeds. This suggests a need for a species‐specific, formulated dry feed for H. gammarus larviculture. Our research represents the first investigation of H. gammarus larval composition and dietary requirements and highlights decreased growth potential associated with providing nutrition solely from generic commercial feed. 相似文献
2.
Aphanomyces astaci presence in Japan: a threat to the endemic and endangered crayfish species Cambaroides japonicus? 下载免费PDF全文
Agata Mrugała Tadashi Kawai Eva Kozubíková‐Balcarová Adam Petrusek 《水产资源保护:海洋与淡水生态系统》2017,27(1):103-114
- Spread of the crayfish plague pathogen, Aphanomyces astaci, by North American crayfish species is considered one of the main reasons for substantial declines and local extinctions of native European crayfish populations. Owing to human introductions, several American crayfish species have become established throughout the world, and thus pose a potential threat to indigenous crayfish populations susceptible to crayfish plague.
- In Japan, two such widespread alien species, Procambarus clarkii and Pacifastacus leniusculus, were introduced for aquaculture purposes in the late 1920s and since then successfully expanded their ranges.
- Aggressive interactions with alien crayfish along with habitat modifications have been considered primarily responsible for drastic declines in populations of the Japanese endemic crayfish, Cambaroides japonicus, observed in the last few decades. However, the presence of the crayfish plague pathogen, to which Japanese crayfish are susceptible, may be expected, and could contribute to these declines.
- Only recently, A. astaci has been reported from Taiwan, and to our knowledge no study focusing on its presence outside of the Western Palearctic has been conducted.
- To fill this gap, 54 P. clarkii and 47 P. leniusculus individuals from five different Japanese locations were screened using molecular methods recommended by the World Organization for Animal Health. Aphanomyces astaci DNA was detected in all studied populations, altogether in 61% and 21% of examined individuals of P. clarkii and P. leniusculus, respectively.
- The results provide the first evidence of A. astaci presence in Japan and highlight the threat of pathogen transmission to C. japonicus populations.
3.
Nikki Baggaley Allan Lilly Kirsty Blackstock Karen Dobbie Adam Carson Fraser Leith 《Soil Use and Management》2020,36(1):19-26
Surface runoff, erosion, compaction and the leaching of potential pollutants from land can degrade the soil resource and damage the water environment, reducing crop yields, causing loss of valuable nutrients and organic matter, together with increasing flood risk. Increasingly, it is recognized that scientific information must be translated into practical tools to change practices and protect the soil and water resource. Working alongside agencies in Scotland, we applied a suite of simple, transparent, rule-based models to identify areas most at risk of exporting sediment and pollutants that may degrade water quality based on field-scale (1:25,000) soil maps. The maps have been used by Scottish Environment Protection Agency, Scottish Water and Scottish Government to assess soil risks to waters from field to regional scale. The work brought scientists together with policy makers, agencies and the water industry to pool their knowledge to apply these practical tools for decision-making. It highlights the need to apply existing knowledge to answer salient questions. All three examples described show that providing the right type of information, which is based on fundamental soils data, can directly influence the implementation of policies, investment and monitoring decisions and provide evidence in support of government. However, this requires both researchers and agency scientists to develop skills as knowledge brokers and to normalize the use of soil data in everyday agency settings. 相似文献
4.
Anette Amtmann Ibrahim Ahmed Petra Zahner-Rimmel Adam Mletzko Lisa Katharina Jordan Martin Oberle Helmut Wedekind Jürgen Christian Sven Michael Bergmann Anna Maria Becker 《Journal of fish diseases》2020,43(2):185-195
In a search for alternative, environmentally friendly and effective disinfecting agents, a commercially available protease—Neutrase®—was tested in this work for inactivation of koi herpesvirus (KHV) and of viral haemorrhagic septicaemia virus (VHSV). For comparison, the stability of these viral pathogens in similar configurations at various pH values and concentrations of peracetic acid or quicklime, typically used for disinfection, was tested. Therefore, virus suspensions were incubated with various concentrations of different agents for 24 hr and the titre of the remaining infectious particles was determined by virus titration. Furthermore, the treatment of both viruses, with the agents at concentrations that were previously appointed as effective, was also examined in the presence of solid material (quartz sand). All procedures investigated in this study, including the protease treatment, were able to reduce the titre of KHV and VHSV below the detection limit of the titration. Although further studies are necessary, this is the first report of the application of a protease for the inactivation of the selected fish pathogens, demonstrating the great potential of the latter for disinfection. 相似文献
5.
Journal of Plant Diseases and Protection - Prior to the first occurrence of chestnut blight in 1976, leaf spot caused by Cylindrosporium castaneae was one of the most important diseases of European... 相似文献
6.
Natalia Siwinska Agnieszka Zak Malwina Slowikowska Artur Niedzwiedz Rafal Ciaputa Izabela Janus Marek Lipiec Lukasz Radulski Adam Szymerowski Marcin Nowak 《Equine Veterinary Education》2023,35(2):e61-e65
Bovine tuberculosis is a contagious and zoonotic disease of animals and humans. In Europe, the number of reported cases of tuberculosis has decreased. Equidae are relatively rarely infected even in endemic areas. The presented report describes a case of chronic Mycobacterium bovis tuberculosis in a 30-year-old female donkey. The donkey initially presented with persistent lymphadenopathy; however, as the disease progressed, weight loss became apparent. To the authors' knowledge, this is the second confirmed case of tuberculosis in a donkey in Europe. 相似文献
7.
Erythrocyte and Biochemical Abnormalities as Diagnostic Markers in Dogs With Hemangiosarcoma Related Hemoabdomen 下载免费PDF全文
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9.
Factors affecting urine reagent strip blood results in dogs and nonhuman primates and interpretation of urinalysis in preclinical toxicology studies: a Multi‐Institution Contract Research Organization and BioPharmaceutical Company Perspective 下载免费PDF全文
10.
Adam C. Margetts Emma Scurrell Smita Das Kerry M. Smith 《Veterinary ophthalmology》2023,26(3):238-242
A 10-month-old female, neutered French Bulldog presented with a history of unilateral right-sided intermittent conjunctivitis and exophthalmos. The patient suffered blunt force trauma to the right eye after a tennis ball impact approximately five months prior to presentation. Examination identified the patient was visual with exophthalmos, lateral strabismus, conjunctival hyperaemia, episcleral congestion, and papilloedema. Magnetic resonance imaging and ultrasonography identified an approximately two centimeter diameter fluid-filled structure directly posterior to the globe leading to displacement of the optic nerve and distortion of the posterior globe wall. Centesis of the lesion demonstrated neutrophilic and macrophagic inflammation with evidence of prior hemorrhage. Within four weeks, the structure had re-filled to its original size and was subsequently excised in its entirety, via a lateral orbitotomy. Histopathologic findings indicated a non-keratinising orbital cyst, the lining of which was consistent with a respiratory epithelial cyst. Recurrence had not occurred seven months' post-surgery. To the author's knowledge, previous reports of retrobulbar respiratory epithelial cysts have not been documented in animals. 相似文献