The Experts below are selected from a list of 7542 Experts worldwide ranked by ideXlab platform
Molly J T Kibenge - One of the best experts on this subject based on the ideXlab platform.
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countermeasures against viral diseases of Farmed Fish
Antiviral Research, 2012Co-Authors: Frederick S B Kibenge, Marcos Godoy, Mark D Fast, Samuel T Workenhe, Molly J T KibengeAbstract:Abstract Farmed Fish provide an increasing fraction of the human food supply, and are of major economic importance in many countries. As in the case of terrestrial agriculture, bringing together large numbers of animals of a single species (i.e., monoculture) increases the risk of infectious disease outbreaks, including viral infections. Aquaculture, in which Farmed Fish are kept at high population densities in close proximity with wild Fish reservoirs, is ideal for the emergence of wild-type pathogens that exist benignly in local wild Fish and/or the spreading of aquatic pathogens to wild Fish that enter into or come into close proximity with net cages and with Fish escaping from them. This paper provides a general review for the nonspecialist of viral diseases of Farmed Fish and how they could be prevented or treated. It has five principal objectives: (1) to provide an update on the most important and emerging viral diseases of salmonid aquaculture; (2) to review general aspects of innate antiviral defense against virus infections in Fish, including recent advances in antiviral signaling; (3) to discuss current principles and practices of vaccinating Fish; (4) to review antiviral drugs that have activity against viruses of Farmed Fish, and current barriers to employing them in aquaculture; and (5) to discuss the growing use of “functional feeds” in salmonid aquaculture to mitigate viral diseases. In conclusion, despite the challenging aquatic environment, it is expected that well thought-out combinations of vaccination and immunostimulants and/or antiviral drugs could provide solid protection against viral diseases of Farmed Fish.
Stephen E Swearer - One of the best experts on this subject based on the ideXlab platform.
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Rapid growth causes abnormal vaterite formation in Farmed Fish otoliths.
The Journal of Experimental Biology, 2017Co-Authors: Tormey Reimer, Tim Dempster, Anna Wargelius, Per Gunnar Fjelldal, Tom Hansen, Kevin A. Glover, Monica Favnebøe Solberg, Stephen E SwearerAbstract:ABSTRACT Sagittal otoliths are essential components of the sensory organs that enable all teleost Fish to hear and maintain balance, and are primarily composed of calcium carbonate. A deformity, where aragonite (the normal crystal form) is replaced with vaterite, was first noted over 50 years ago but its underlying cause is unresolved. We evaluated the prevalence of vateritic otoliths from two captive rearing studies which suggested that fast growth, due to environmental rather than genetic control, led to vaterite development. We then tested this by varying light and temperature to create phenotypes with different growth rates, which resulted in fast growers (5 times larger) having 3 times more vaterite than slow growers. A decrease in either the ratio of otolith matrix proteins (otolin-1/OMM-64) or [Ca 2+ ]/[CO 3 2− ] may explain why fast growth causes vaterite deposition. As vaterite decreases hearing sensitivity, reducing growth rates in hatcheries may improve the welfare of Farmed Fish and increase the success of conservation efforts.
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high prevalence of vaterite in sagittal otoliths causes hearing impairment in Farmed Fish
Scientific Reports, 2016Co-Authors: T Reimer, Tim Dempster, Fletcher Warrenmyers, Arne Johan Jensen, Stephen E SwearerAbstract:The rapid growth of aquaculture raises questions about the welfare status of mass-produced species. Sagittal otoliths are primary hearing structures in the inner ear of all teleost (bony) Fishes and are normally composed of aragonite, though abnormal vaterite replacement is sometimes seen in the wild. We provide the first widespread evaluation of the prevalence of vaterite in otoliths, showing that Farmed Fish have levels of vaterite replacement over 10 times higher than wild Fish, regardless of species. We confirm this observation with extensive sampling of wild and Farmed Atlantic salmon in Norway, the world’s largest producer and verify that vateritic otoliths are common in Farmed salmon worldwide. Using a mechanistic model of otolith oscillation in response to sound, we demonstrate that average levels of vaterite replacement result in a 28–50% loss of otolith functionality across most of a salmonid’s known hearing range and throughout its life cycle. The underlying cause(s) of vaterite formation remain unknown, but the prevalence of hearing impairment in Farmed Fish has important implications for animal welfare, the survival of escapees and their effects on wild populations and the efficacy of restocking programs based on captive-bred Fish.
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an industry scale mass marking technique for tracing Farmed Fish escapees
PLOS ONE, 2015Co-Authors: Fletcher Warrenmyers, Tim Dempster, Per Gunnar Fjelldal, Thomas Willum Hansen, Stephen E SwearerAbstract:Farmed Fish escape and enter the environment with subsequent effects on wild populations. Reducing escapes requires the ability to trace individuals back to the point of escape, so that escape causes can be identified and technical standards improved. Here, we tested if stable isotope otolith fingerprint marks delivered during routine vaccination could be an accurate, feasible and cost effective marking method, suitable for industrial-scale application. We tested seven stable isotopes, 134Ba, 135Ba, 136Ba, 137Ba, 86Sr, 87Sr and 26Mg, on Farmed Atlantic salmon reared in freshwater, in experimental conditions designed to reflect commercial practice. Marking was 100% successful with individual Ba isotopes at concentrations as low as 0.001 µg. g-1 Fish and for Sr isotopes at 1 µg. g-1 Fish. Our results suggest that 63 unique fingerprint marks can be made at low cost using Ba (0.0002 – 0.02 $US per mark) and Sr (0.46 – 0.82 $US per mark) isotopes. Stable isotope fingerprinting during vaccination is feasible for commercial application if applied at a company level within the world’s largest salmon producing nations. Introducing a mass marking scheme would enable tracing of escapees back to point of origin, which could drive greater compliance, better farm design and improved management practices to reduce escapes.
Joann C Leong - One of the best experts on this subject based on the ideXlab platform.
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dna vaccines against viral diseases of Farmed Fish
Fish & Shellfish Immunology, 2013Co-Authors: Oystein Evensen, Joann C LeongAbstract:Immunization by an antigen-encoding DNA was approved for commercial sale in Canada against a Novirhabdovirus infection in Fish. DNA vaccines have been particularly successful against the Novirhabdoviruses while there are reports on the efficacy against viral pathogens like infectious pancreatic necrosis virus, infectious salmon anemia virus, and lymphocystis disease virus and these are inferior to what has been attained for the novirhabdoviruses. Most recently, DNA vaccination of Penaeus monodon against white spot syndrome virus was reported. Research efforts are now focused on the development of more effective vectors for DNA vaccines, improvement of vaccine efficacy against various viral diseases of Fish for which there is currently no vaccines available and provision of co-expression of viral antigen and immunomodulatory compounds. Scientists are also in the process of developing new delivery methods. While a DNA vaccine has been approved for commercial use in Farmed salmon in Canada, it is foreseen that it is still a long way to go before a DNA vaccine is approved for use in Farmed Fish in Europe.
Frederick S B Kibenge - One of the best experts on this subject based on the ideXlab platform.
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countermeasures against viral diseases of Farmed Fish
Antiviral Research, 2012Co-Authors: Frederick S B Kibenge, Marcos Godoy, Mark D Fast, Samuel T Workenhe, Molly J T KibengeAbstract:Abstract Farmed Fish provide an increasing fraction of the human food supply, and are of major economic importance in many countries. As in the case of terrestrial agriculture, bringing together large numbers of animals of a single species (i.e., monoculture) increases the risk of infectious disease outbreaks, including viral infections. Aquaculture, in which Farmed Fish are kept at high population densities in close proximity with wild Fish reservoirs, is ideal for the emergence of wild-type pathogens that exist benignly in local wild Fish and/or the spreading of aquatic pathogens to wild Fish that enter into or come into close proximity with net cages and with Fish escaping from them. This paper provides a general review for the nonspecialist of viral diseases of Farmed Fish and how they could be prevented or treated. It has five principal objectives: (1) to provide an update on the most important and emerging viral diseases of salmonid aquaculture; (2) to review general aspects of innate antiviral defense against virus infections in Fish, including recent advances in antiviral signaling; (3) to discuss current principles and practices of vaccinating Fish; (4) to review antiviral drugs that have activity against viruses of Farmed Fish, and current barriers to employing them in aquaculture; and (5) to discuss the growing use of “functional feeds” in salmonid aquaculture to mitigate viral diseases. In conclusion, despite the challenging aquatic environment, it is expected that well thought-out combinations of vaccination and immunostimulants and/or antiviral drugs could provide solid protection against viral diseases of Farmed Fish.
Oystein Evensen - One of the best experts on this subject based on the ideXlab platform.
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dna vaccines against viral diseases of Farmed Fish
Fish & Shellfish Immunology, 2013Co-Authors: Oystein Evensen, Joann C LeongAbstract:Immunization by an antigen-encoding DNA was approved for commercial sale in Canada against a Novirhabdovirus infection in Fish. DNA vaccines have been particularly successful against the Novirhabdoviruses while there are reports on the efficacy against viral pathogens like infectious pancreatic necrosis virus, infectious salmon anemia virus, and lymphocystis disease virus and these are inferior to what has been attained for the novirhabdoviruses. Most recently, DNA vaccination of Penaeus monodon against white spot syndrome virus was reported. Research efforts are now focused on the development of more effective vectors for DNA vaccines, improvement of vaccine efficacy against various viral diseases of Fish for which there is currently no vaccines available and provision of co-expression of viral antigen and immunomodulatory compounds. Scientists are also in the process of developing new delivery methods. While a DNA vaccine has been approved for commercial use in Farmed salmon in Canada, it is foreseen that it is still a long way to go before a DNA vaccine is approved for use in Farmed Fish in Europe.
