Single-celled parasites of the genus Spironucleus are known to produce serious illness in farmed and aquarium fish.
In farmed salmon, these parasites create foul-smelling, puss-filled abscesses in muscles and internal organs. After the first outbreaks of this disease were described in farmed salmon in the late 1980’s, it was assumed that the cause was Spironucleus barkhanus, which is a fairly common parasite in the intestine of wild grayling and Arctic char.
In these fish species, however, the parasite is benign. For his doctorate, Jørgensen completed genetic studies showing that the disease-causing parasite in farmed salmon is genetically quite different from the species one finds in wild salmonids, although they appear to be identical, even under high magnification in an electron microscope. Based on this observation, the parasite that causes disease in farmed salmon has now been described as a new species – Spironucleus salmonicida.
“Our work has shown that genetic methods need to be utilised for correct identification of single-celled parasites of the genus Spironucleus. Parasites that appear to be identical morphologically may in fact be significantly different genetically. An exact identification of organisms that produce disease is extremely important in the fight to find the cause of disease outbreaks and provides an important contribution to finding appropriate diagnostic methods”, says Anders Jørgensen.
Jørgensen carried out similar studies with other Spironucleus species, which he also incorporatd into his doctoral thesis. Spironucleus vortens, which causes disease in aquarium fish, is also found in wild carp in Norway. Even though these parasites appear to be identical, they are very different genetically. Jørgensen also addressed the cod parasite Spironucleus torosus, which is found in several genetic variants. Based on these new findings, Jørgensen discusses whether the genetic differences between the variants provides a basis for splitting them into separate species.
Finally, Jørgensen investigated relationships between a series of species. These investigations showed that parasites from other Spironucleus families form three primary groups, which reflect the different environments their host species live in. His thesis hints that each of these groups may constitute a separate genus.
Magnhild Jenssen | alfa
Complementing conventional antibiotics
24.05.2018 | Goethe-Universität Frankfurt am Main
Building a brain, cell by cell: Researchers make a mini neuron network (of two)
23.05.2018 | Institute of Industrial Science, The University of Tokyo
A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.
The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
24.05.2018 | Ecology, The Environment and Conservation
24.05.2018 | Medical Engineering
24.05.2018 | Physics and Astronomy