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991.
Laura A. Carvalho Shona K. Whyte Laura M. Braden Sara L. Purcell Anthony J. Manning Anne Muckle Mark D. Fast 《Journal of fish diseases》2020,43(4):459-473
This study was conducted to determine the effects of a co-infection with Moritella viscosa at different exposure levels of sea lice Lepeophtheirus salmonis in Atlantic salmon (Salmo salar). M. viscosa (1.14 × 106 cfu/ml) was introduced to all experimental tanks at 10 days post-lice infection (dpLs). Mean lice counts decreased over time in both the medium lice co-infection (31.5 ± 19.0 at 7 dpLs; 16.9 ± 9.3 at 46 dpLs) and high lice co-infection (62.0 ± 10.8 at 7 dpLs; 37.6 ± 11.3 at 46 dpLs). There were significantly higher mortalities and more severe skin lesions in the high lice co-infected group compared to medium lice co-infected group or M. viscosa-only infection. Quantitative gene expression analysis detected a significant upregulation of genes in skin from the high lice co-infection group consistent with severe inflammation (il-8, mmp-9, hep, saa). Skin lesions retrieved throughout the study were positive for M. viscosa growth, but these were rarely located in regions associated with lice. These results suggest that while M. viscosa infection itself may induce skin lesion development in salmon, co-infection with high numbers of lice can enhance this impact and significantly reduce the ability of these lesions to resolve, resulting in increased mortality. 相似文献
992.
Md Javed Foysal Farhana Momtaz Md Hazrat Ali Muhammad A. B. Siddik Md Reaz Chaklader Md Mahbubur Rahman Md Shamsul Haque Prodhan Anthony Cole 《Journal of fish diseases》2019,42(4):465-475
Aerolysin (aer) is one of the most important and abundant virulence factors in the infection of fish by Aeromonas veronii. A comprehensive study on the molecular characterization and pathogenicity of the aer gene from 34 A. veronii isolates from diseased carp and catfish was carried out and its interactome was analysed to observe the functional correlations between aer and other proteins within the A. veronii network. The PCR‐based amplification of aer from the 34 isolates of A. veronii showed more aer‐positive isolates from catfish with a high pathogenic potential in the in vivo challenge test than the carp fish. The analysis of aer gene sequence from challenged fish revealed significant sequence divergence according to the types and geographical distribution of the fish. The networking analysis of aer from the model A. veronii B565 revealed histidine kinase (cheA) as the most functional interacting partner. The study of the interaction between aer from the experimental A. veronii and cheA demonstrated that the A chain of cheA plays a more important role than the corresponding B chain during contact, and a linker sequence of 15 residues controlled the entire interaction process. Therefore, cheA could be an excellent drug target for controlling A. veronii infection of fish. 相似文献
993.
Md Javed Foysal Mahbubul Alam Farhana Momtaz Md Reaz Chaklader Muhammad A. B. Siddik Anthony Cole Ravi Fotedar Md Mahbubur Rahman 《Aquaculture Research》2019,50(8):2107-2116
This study was conducted to characterize the causative agent of streptococcosis in tilapia (Oreochromis niloticus) and control of Streptococcus infection by means of garlic (Allium sativum) supplementation. The morphological, biochemical and polymerase chain reaction amplification confirmed 11 isolates belong to Streptococcus iniae from the infected fish eyes and tissue samples. Random screening of 12 well‐known medicinal plant parts against S. iniae revealed the garlic extract as the most effective herbal recovery against Streptococcus infection. In vivo challenge test with dietary supplementation of garlic powder significantly improved survival rates of fish against S. iniae infections, and modulate the microbial community and cytokine gene expression profiling in the intestine of the experimental tilapia. Among the two garlic supplemented treatments, 1.0 g garlic supplemented diet significantly increased (p < 0.05) the survival rates of tilapia and the gut bacterial operational transitional units abundance for Proteobacteria and Tenericutes, the phyla associated with healthy intestinal flora. The bacterial diversity index also found high with garlic supplemented diets. Significant upregulations of IL‐10 and IL‐17F gene expression in the intestinal tissue were observed with 1.0 g garlic supplemented diet where IL‐8 and IL‐1β expression levels were relatively static. The dietary supplementation of garlic, therefore, could be effective in the prevention of S. iniae infection in fish. 相似文献
994.
Chrysoula Gubili Robert Schabetsberger Christine Poellabauer Becky Bates Rosa M. Wagstaff Lewis M. Woodward Ursula Sichrowsky Alexander Scheck David T. Boseto Eric Feunteun Anthony Acou Robert Jehle 《Fisheries Management and Ecology》2019,26(1):31-41
Understanding the population structure of tropical anguillids residing in the Pacific is vital for their conservation management. Here, the population genetic structure of five sympatric freshwater eels (Anguilla marmorata Quoy & Gaimard, A. megastoma Kaup, A. obscura Steindachner, A. reinhardtii Günther and A. australis Richardson) across 11 western South Pacific (WSP) islands was investigated based on partial nucleotide sequences of the mtDNA control region and the nuclear GTH2b genes of 288 newly collected samples jointly with existing sequences. WSP anguillids are characterised by overall high levels of genetic diversity. Both mtDNA and nuclear sequences provided no evidence for distinct geographic clines or barriers in any of the species across the WSP. The occurrence of admixed individuals between A. marmorata and A. megastoma was confirmed, and a new possible occurrence of a further species was revealed (A. interioris Whitley on Bougainville Island). All species showed evidence for demographic population growth in the Pleistocene, and a subsequent population reduction for A. megastoma. Common spawning grounds and mixing of larvae by ocean currents could promote the lack of pronounced isolation by distance, a finding that has significant implications for the future management of anguillids in the area. 相似文献
995.
The recent characterization of triallate-resistant lines of wild oat (Avena fatua L.) deficient in triallate sulfoxidation provides an experimental system to investigate and differentiate the effects of triallate and triallate sulfoxide on wax and lipid biosynthesis. Greenhouse applications of triallate dramatically reduced epicuticular wax deposition in susceptible (S) but not resistant (R) wild oats. Triallate treatment had no effect on in-vivo concentrations of C12 to C26 fatty acids and fatty alcohols in R plants, while elongated fatty acid fractions (C>18) were significantly reduced in S plants. In contrast, treatment with triallate sulfoxide reduced in-vivo concentrations of elongated fatty acids equally in R and S, supporting the hypothesis that triallate sulfoxide is more inhibitory than triallate towards fatty acid elongases. Although de-novo synthesis of short-chain fatty acids was not affected by triallate or triallate sulfoxide in R or S plants, synthesis of elongated fatty acid fractions was dramatically reduced in S plants by triallate. Fatty acid biosynthesis in R and S plants was equally sensitive to triallate sulfoxide. The results support the idea that in-vivo triallate sulfoxidation is necessary for herbicidal activity, and confirm that reduced rates of triallate sulfoxidation confer resistance in R wild oats. © 1997 SCI. 相似文献
996.
Hannah Bailey Ann Kendall Anthony D. Martin Sherry L. Hyndman David W. 《Landscape Ecology》2020,35(12):2843-2861
Landscape Ecology - Freshwater coastal wetlands provide numerous ecosystem services, including habitat, nutrient uptake, coastal stabilization, and aesthetic value, but the integrity of these... 相似文献
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999.
Xia LIANG Jizheng HE Fusuo ZHANG Qirong SHEN Jinshui WU Iain M. YOUNG Anthony G. O'DONNELL Ligang WANG Enli WANG Julian HILL Deli CHEN 《农业科学与工程前沿(英文版)》2020,7(3):347-355
Soil is the foundation for sustainable food production and environmental protection. Created by unsustainable land management practices and a range of social, economic and environmental drivers, soil degradation and pollution have been an ongoing threat to international food security and environmental quality. Soil degradation and pollution assessments are, however, often focused on the soil itself with little scope to devise new soil management approaches that match food production systems and/or environmental protection. This study draws lessons from an Australia-China Joint Research Center Program, Healthy Soils for Sustainable Food Production and Environmental Quality: a research platform that has brought together multi-disciplinary approaches from world-renowned universities and research organizations in Australia and China. To this end, a framework is presented for future soil management in a new way that combines excellence in research, industry and policymakers in a partnership that will ensure not only the right focus of the research but also that high-quality outputs will be transferable to industry and end-users. 相似文献
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