? Myxobolus cerebralis
Triactinomyxon stage of Myxobolus cerebralis. Note the three "tails".
Scientific classification
Kingdom: Animalia Phylum: Myxozoa Class: Myxosporea Order: Bivalvulida Family: Myxobolidae Genus: Myxobolus Species: M. cerebralis
Binomial name
Myxobolus cerebralis Hofer, 1903
Synonyms
Myxosoma cerebralis Triactinomyxon dubium Triactinomyxon gyrosalmo

Myxobolus cerebralis is a myxosporean parasite of salmonids (salmon, trout, and their allies) that causes whirling disease in farmed salmon and trout and also in wild fish populations. It was first described from rainbow trout in Germany a century ago, but its range has spread and it has appeared in most of Europe (including Russia), the United States, South Africa^[1] and other countries. In the 1980s, it was discovered that M. cerebralis needs to infect a tubificid oligochaete (a kind of segmented worm) to complete its life-cycle^[2]. The parasite infects its hosts with its cells after piercing them with polar filaments ejected from nematocyst-like capsules. Image File history File links Myxobolus cerebralis triactinomyxon. ... Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms (as opposed to folk taxonomy). ... Phyla Subregnum Parazoa Porifera (sponges) Subregnum Agnotozoa Placozoa (trichoplax) Orthonectida (orthonectids) Rhombozoa (dicyemids) Subregnum Eumetazoa Radiata (unranked) (radial symmetry) Ctenophora (comb jellies) Cnidaria (coral, jellyfish, anemones) Bilateria (unranked) (bilateral symmetry) Acoelomorpha (basal) Orthonectida (parasitic to flatworms, echinoderms, etc. ... Classes Malacosporea Myxosporea The Myxozoa are a group of microscopic, parasitic animals. ... Orders Bivalvulida Multivalvulida The Myxosporea are a class of microscopic parasites, belonging to the phylum Myxozoa. ... Families Sphaeromyxidae Myxidiidae Ortholineidae Sinuolineidae Fabesporidae Ceratomyxidae Sphaerosporidae Chloromyxidae Auerbachiidae Alatasporidae Parvicapsulidae Myxobolidae The Bivalvulida is an order of myxosporean parasites which contains a number of species which cause economically significant losses to aquaculture and fisheries, such as Myxobolus cerebralis and Ceratomyxa shasta. ... Genera Myxobolus Spirosuturia Unicauda Dicauda Phlogospora Laterocaudata Henneguya Tetrauronema Thelohanellus Neothelohanellus Neohenneguya Trigonosporus The Myxobolidae are a family of myxosporean parasites which typically infect freshwater fishes, and includes the economically significant species, Myxobolus cerebralis. ... Synonyms MyxosomaTheolan, 1892 LentosporaPlehn, 1905 FacieplatycaudataWyatt, 1979 Myxobolus is a genus of myxozoa that includes important parasites of fish like Myxobolus cerebralis. ... In biology, binomial nomenclature is the formal method of naming species. ... Bruno Hofer (1861 – 1916) was a German fishery scientist, credited with being the founder of fish pathology. ... In scientific classification, synonymy is the existence of multiple systematic names to label the same organism. ... Orders Bivalvulida Multivalvulida The Myxosporea are a class of microscopic parasites, belonging to the phylum Myxozoa. ... A parasite is an organism that spends a significant portion of its life in or on the living tissue of a host organism and which causes harm to the host without immediately killing it. ... Genera (see text) Salmonidae is a family of ray-finned fish, the only family of order Salmoniformes. ... The Chinook or King Salmon is the largest salmon in North America and can grow up to 58 long and 125 pounds. ... Rainbow trout (Oncorhynchus mykiss) Biwa trout (Oncorhynchus masou subsp) Trout is the common name given to a number of species of freshwater fish belonging to the salmon family, Salmonidae. ... A demonstration aquaculture facility Fish farming is the principal form of aquaculture. ... Fish stocks are subpopulations of a particular species of fish, for which intrinsic parameters (growth, recruitment, mortality and fishing mortality) are the only significant factors in determining population dynamics, while extrinsic factors (immigration and emmigration) are considered to be insignificant. ... Binomial name Oncorhynchus mykiss Walbaum, 1792 The rainbow trout (Oncorhynchus mykiss, formerly Salmo iridia) is a single species of trout native to the Pacific Ocean and in North American rivers and lakes west of the Rocky Mountains. ... Europe is conventionally considered one of the seven continents of Earth which, in this case, is more a cultural and political distinction than a physiographic one, leading to various perspectives about Europes borders. ... Subfamilies Phallodrilinae Limnodriloidinae Rhyacodrilinae Tubificinae Phallodrilinae Limnodriloidinae Rhyacodrilinae Tubificinae The Tubificidae are a family of clitellate oligochaete worms like the sludge worm, Tubifex tubifex. ... Orders Arhynchobdellida Haplotaxida Rhynchobdellida The Oligochaeta or few-bristled worms (singular Oligochaete, IPA /ˈɒlɪgoʊˌkit/) are well-segmented Annelids, most with a spacious coelom that is used as a hydroskeleton. ... Classes and subclasses Class Polychaeta (paraphyletic?) Class Clitellata    Oligochaeta - Earthworms and others    Acanthobdellida    Branchiobdellida    Hirudinea - Leeches Class Myzostomida Class Archiannelida (polyphyletic) Class Echiura *Some authors consider the subclasses under Clitellata to be classes The annelids, collectively called Annelida, are a large phylum of animals, comprising the segmented worms, with about... Myxospore drawn by Dr. Thomas L. Wellborn, Jr. ... Cnidocytes are prey-capture and defensive cells found on animals of the phylum Cnidaria. ...

Whirling disease afflicts juvenile fish (fingerlings and fry) and causes skeletal deformation and neurological damage. Fish "whirl" rather than swim forward, find feeding difficult, and are more vulnerable to predators. The mortality rate is high for fingerlings, up to 90% of infected populations, and those that do survive are deformed by the parasite residing in their cartilage and bone. They act as a reservoir for the parasite, which is released into water following the fish's death. M. cerebralis is one of the most economically important myxozoans in fish as well as one of the most pathogenic. It was the first myxosporean whose pathology and symptoms were described scientifically^[3]. The parasite is not transmissible to humans. Skeleton of a Blue Whale In biology, the skeleton or skeletal system is the biological system providing physical support in living organisms. ... The nervous system of an animal coordinates the activity of the muscles, monitors the organs, constructs and processes input from the senses, and initiates actions. ... This snapping turtle is trying to make a meal of a Canada goose, but the goose is too wary. ... Cartilage is a type of dense connective tissue. ... Grays illustration of a human femur, a typically recognized bone. ...

Taxonomy

The taxonomy and naming of both M. cerebralis and of myxozoans in general have complicated histories. It was originally thought that this parasite infected fish brains (hence the specific epithet cerebralis), however it quickly became apparent that while it can be found in the nervous system, it primarily infects cartilage and skeletal tissue. Attempts to change the name to Myxobolus chondrophagus, which would more accurately describe the organism, failed because of nomenclature rules^[4]. Later, it became apparent that organisms previously called Triactinomyxon dubium and T. gyrosalmo (class Actinosporea) were in fact triactinomyxon stages of M. cerebralis, whose life cycle was expanded to include the triactinomyxon stage^[5]. Similarly, other actinosporeans were folded into the life cycles of various myxosporeans. Taxonomy (from Greek verb tassein = to classify and nomos = law, science, cf economy) may refer to: the science of classifying living things (see alpha taxonomy) a system of classification in some other field Taxonomy was once only the science of classifying living organisms, but later the word was applied in... A specific epithet is a biological epithet of a species. ... The nervous system of an animal coordinates the activity of the muscles, monitors the organs, constructs and also stops input from the senses, and initiates actions. ... Cartilage is a type of dense connective tissue. ... Skeleton of a Blue Whale In biology, the skeleton or skeletal system is the biological system providing physical support in living organisms. ... In biology, binomial nomenclature is the formal method of naming species. ... Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ... Orders Bivalvulida Multivalvulida The Myxosporea are a class of microscopic parasites, belonging to the phylum Myxozoa. ...

Today, the myxozoans, previously thought to be multicellular protozoans are considered animals by many scientists, though their status has not officially changed. Recent molecular studies suggest that they are related to Bilateria or Cnidaria, with Cnidaria being closer morphologically because both groups have extrusive filaments^[6], but with Bilateria being somewhat closer in some genetic studies^[7]. Protozoa (in Greek protos = first and zoon = animal) are single-celled creatures with nuclei that show some characteristics usually associated with animals, most notably mobility and heterotrophy. ... Phyla Subregnum Parazoa Porifera (sponges) Subregnum Agnotozoa Placozoa (trichoplax) Orthonectida (orthonectids) Rhombozoa (dicyemids) Subregnum Eumetazoa Radiata (unranked) (radial symmetry) Ctenophora (comb jellies) Cnidaria (coral, jellyfish, anemones) Bilateria (unranked) (bilateral symmetry) Acoelomorpha (basal) Orthonectida (parasitic to flatworms, echinoderms, etc. ... Illustration of the different types of symmetry of Life Forms On Earth. ... Classes Anthozoa- Corals and sea anemones Cubozoa- Sea wasps or box jellyfish Hydrozoa- Hydroids, hydra-like animals Scyphozoa- Jellyfish Cnidaria (silent c - pronounced // from New Latin cnida, fr. ...

Morphology

Diagram of the structure of a triactionmyxon stage spore of Myxobolus cerebralis

M. cerebralis has many diverse stages ranging from single cells to relatively large spores, not all of which have been studied in detail. Image File history File links Download high resolution version (644x1092, 12 KB)An actinomyxon spore of Myxobolus cerebralis. ... Image File history File links Download high resolution version (644x1092, 12 KB)An actinomyxon spore of Myxobolus cerebralis. ... It has been suggested that extracellular be merged into this article or section. ...

Triactinomyxon stage

The stages that infect fish, called triactinomyxon spores, are made of a single style that is about 150 micrometers (µm) long and three processes or "tails" that are each about 200 micrometers long. A sporoplasm packet at the end of the style contains 64 germ cells surrounded by a cellular envelope^[8]. There are also three polar capsules, each of which contains a coiled polar filament between 170 and 180 µm long.^[9] Polar filaments in both this stage and in the myxospore stage (see picture above) rapidly shoot into the body of the host, creating an opening through which the sporoplasm can enter. A micrometre (American spelling: micrometer), symbol µm, is an SI unit of length. ... Alataspora solomoni, a myxosporean parasite of Atlantic Horse Mackerel, showing the arrangement of the polar capsules on either side of the sutural line. ... Myxospore drawn by Dr. Thomas L. Wellborn, Jr. ... Orders Bivalvulida Multivalvulida The Myxosporea are a class of microscopic parasites, belonging to the phylum Myxozoa. ...

Sporoplasm stage

Upon contact with fish hosts and firing of the polar capsules, the sporoplasm contained within the central style of the triactinomyxon migrates into the epithelium or gut lining. Firstly, this sporoplasm undergoes mitosis to produce more amoeboid cells, which migrate into deeper tissue layers, in order to reach the cerebral cartilage ^[10]. Light micrograph of a newt kidney cell in early anaphase of mitosis. ... Amoeba (Chaos diffluens) Foraminiferan (Ammonia tepida) Heliozoan (Actinophrys sol) Amoeboids are cells that move or feed by means of temporary projections, called pseudopods (false feet). ...

Myxosporean stage

Myxospores, which develop from sporogonic cell stages inside fish hosts, are lenticular. They have a diameter of about 10 micrometers and are made of six cells. Two of these cells form polar capsules, two merge to form a binucleate sporoplasm, and two form protective valves^[11]. Myxospores are infective to oligochaetes, and are found among the remains of digested fish cartilage. They are often difficult to distinguish from related species because of morphological similarities across genera. Though M. cerebralis is the only myxosporean ever found in salmonid cartilage, other visually similar species may be present in the skin, nervous system, or muscle^[12]. In biology, a genus (plural genera) is a taxonomic grouping. ... The nervous system of an animal coordinates the activity of the muscles, monitors the organs, constructs and also stops input from the senses, and initiates actions. ... A top-down view of skeletal muscle Muscle is the contractile tissue of the body and is derived from the mesodermal layer of embryonic germ cells. ...

Life cycle

Life cycle of M. cerebralis. Click to enlarge.

Myxobolus cerebralis has a two-host life-cycle involving a salmonid fish and a tubificid oligochaete. So far, the only worm known to be susceptible to M. cerebralis infection is Tubifex tubifex^[13], though what scientists currently call T. tubifex may in fact be more than one species^[14]. First, myxospores are ingested by tubificid worms. In the gut lumen of the worm, the spores extrude their polar capsules and attach to the gut epithelium by polar filaments. The shell valves then open along the suture line and the binucleate germ cell penetrates between the intestinal epithelial cells of the worm. This cell multiplies, producing many amoeboid cells by an asexual cell fission process called merogony. As a result of the multiplication process, the intercellular space of the epithelial cells in more than 10 neighbouring worm segments may become infected^[15]. Download high resolution version (500x624, 165 KB)The life cycle of the myxosporean parasite, Myxobolus cerebralis. ... Download high resolution version (500x624, 165 KB)The life cycle of the myxosporean parasite, Myxobolus cerebralis. ... Binomial name Tubifex tubifex (Müller, 1774) Tubifex tubifex, also called the sludge worm, is a species of tubificid segmented worm that inhabits the sediments of lakes and rivers on several continents. ... For the Physics term GUT, please refer to Grand unification theory The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and... In anatomy, the lumen is the cavity or channel within a tube or tubular structure, such as the vascular lumen of a blood vessel, along which blood flows. ... Alataspora solomoni, a myxosporean parasite of Atlantic Horse Mackerel, showing the arrangement of the polar capsules on either side of the sutural line. ... In zootomy, epithelium is a tissue composed of a layer of cells. ... Myxospore drawn by Dr. Thomas L. Wellborn, Jr. ... Amoeba (Chaos diffluens) Foraminiferan (Ammonia tepida) Heliozoan (Actinophrys sol) Amoeboids are cells that move or feed by means of temporary projections, called pseudopods (false feet). ... Binary fission Binary fission is the form of asexual reproduction used by most prokaryotes to reproduce. ... Merogony is a word with two biological meanings: Merogony is an asexual replication process used by some Protozoan parasites that increases the number of infective cells by multiple fission. ...

Around 60–90 days post-infection, sexual cell stages of the parasite undergo sporogenesis, and develop into pansporocysts, each of which contains eight triactinomyxon-stage spores. These spores are released from the oligochaete anus into the water^[16]. Alternatively, a fish can become infected by eating an infected oligochaete^[17]. Infected tubificids can release triactinomyxons for at least 1 year^[18]. The triactinomyxon spores swim through the water to infect a salmonid through the skin. Penetration of the fish by these spores takes only a few seconds. Within five minutes, a sac of germ cells called a sporoplasm has entered the fish epidermis, and within a few hours, the sporoplasm splits into individual cells that will spread through the fish^[19]. Epidermis is the outermost layer of the skin. ...

Within the fish, there are both intracellular and extracellular stages that reproduce in its cartilage by asexual endogeny, meaning that new cells grow from within old cells. The final stage within fish is the myxospore, which is formed by sporogony. They are released into the environment when the fish decomposes or is eaten^[20]. Some recent research indicates that some fish may expel viable myxospores while still alive^[21]. In the life-cycle of apicomplexan protozoa, sporozoites are cells that infect new hosts. ...

Myxospores are extremely tough: "it was shown that Myxobolus cerebralis spores can tolerate freezing at ­-20°C for at least 3 months, aging in mud at 13°C for at least 5 months, and passage through the guts of northern pike Esox lucius or mallards Anas platyrhynchos without loss of infectivity" to worms^[22]. Triactinomyxons are much shorter lived, surviving 34 days or less, depending on temperature^[23]. caught by an angler in the river Dráva, Hungary. ... Binomial name Anas platyrhynchos Linnaeus, 1758 Subspecies (Common Mallard) (Greenland Mallard) (Mexican Duck) The Mallard (Anas platyrhynchos (litt: flat billed duck[1])), also known in North America as the Wild Duck, is a common and widespread dabbling duck which breeds throughout the temperate and sub-tropical areas of North America...

Pathology

Skeletal deformation in a mature Brook trout caused by M. cerebralis infection. Photo by Dr. Thomas L. Wellborn, Jr.

M. cerebralis infections have been reported from a wide range of salmonid species: 8 species of "Atlantic" salmonids, Salmo; 4 species of "Pacific" salmonids, Onchorhynchus; 4 species of Char, Salvelinus; the Grayling, Thymallus thymallus; and the Huchen, Hucho hucho^[24]. M. cerebralis causes damage to its fish hosts through attachment of triactinomyxon spores and the migrations of various stages through tissues and along nerves, as well as by digesting cartilage ^[25]. The fish's tail may darken, but aside from lesions on cartilage, internal organs generally appear healthy ^[26]. Other symptoms include skeletal deformities and "whirling" behavior (tail-chasing) in young fish, which was thought to have been caused by a loss of equilibrium, but is actually caused by damage to the spinal cord and lower brain stem^[27]. Experiments have shown that fish can kill Myxobolus in their skin (possibly using antibodies), but that the fish do not attack the parasites once they have migrated to the central nervous system. This response varies from species to species^[28]. This image is scanned from the collection of Dr. Thomas L. Wellborn, Jr. ... This image is scanned from the collection of Dr. Thomas L. Wellborn, Jr. ... Binomial name Salvelinus fontinalis (Mitchill, 1814) The brook trout (Salvelinus fontinalis) is a species of fish in the salmon family (family Salmonidae) of order Salmoniformes. ... Species (see text) Salmo Linnaeus, 1758, is a genus of fish in the salmon family (Salmonidae) that includes many familiar species of salmon and trout. ... Onchorhynchus is the genus of all pacific coast salmonids. ... Species (see text) Salvelinus is a genus of Salmonid fish, referring to Char or Charr. ... Binomial name Thymallus thymallus (Linnaeus, 1758) For other uses of grayling, see Grayling. ... Binomial name Hucho hucho (Linnaeus, 1758) The huchen (Hucho hucho) is a species of freshwater fish in the salmon family (family Salmonidae) of order Salmoniformes. ... Wikipedia does not yet have an article with this exact name. ...

In T. tubifex, the release of triactinomyxon spores from the intestinal wall damages the worm’s mucosa; this may happen thousands of times in a single worm, and it is believed that this can impair nutrient absorption^[29]. Also, infected worms have lower body mass and may be discolored^[30]. Spores are released from the worm almost exclusively when the temperature is between 10°C and 15°C, so fish in warmer or cooler waters are less likely to be infected, and infection rates vary seasonally^[31]. The intestine is the portion of the alimentary canal extending from the stomach to the anus and, in humans and other mammals, consists of two segments, the small intestine and the large intestine. ... The mucous membranes (or mucosa) are linings of ectodermic origin, covered in epithelium, that line various body cavities and internal organs. ...

Susceptibility

Fish size, age, concentration of triactinomyxon spores, and water temperature all affect infection rates in fish, as does the species of the fish in question^[32]. The disease has the biggest impact on fish less than five months old because their skeleton has not ossified. This makes young fish more susceptible to deformities^[33] and provides M. cerebralis more cartilage on which to feed^[34]. In one study of seven species of many strains, brook trout and rainbow trout (except one strain) were far more heavily affected by M. cerebralis after two hours of exposure than other species were, while bull trout, Chinook salmon, brown trout, and arctic grayling were least severely affected^[35]. While brown trout may harbor the parasite, they typically do not show any symptoms, and this species may have been M. cerebralis' original host^[36]. This lack of symptoms in brown trout meant that the parasite was not discovered until after nonnative rainbow trout were introduced in Europe^[37]. The susceptibility of various salmonids is listed in Salmonid susceptibility to whirling disease. Ossification is the process of bone formation, in which connective tissues, such as cartilage are turned to bone or bone-like tissue. ... Binomial name Salvelinus fontinalis (Mitchill, 1814) The brook trout (Salvelinus fontinalis) is a species of fish in the salmon family (family Salmonidae) of order Salmoniformes. ... Binomial name Oncorhynchus mykiss Walbaum, 1792 The rainbow trout (Oncorhynchus mykiss, formerly Salmo iridia) is a single species of trout native to the Pacific Ocean and in North American rivers and lakes west of the Rocky Mountains. ... Binomial name Salvelinus confluentus Suckley, 1859 The bull trout (Salvelinus confluentus) is a char of the family Salmonidae. ... Binomial name Oncorhynchus tshawytscha (Walbaum, 1792) The Chinook salmon (Oncorhynchus tshawytscha) (derived from Russian чавыча), is a species of anadromous fish in the salmon family. ... Binomial name Salmo trutta Linnaeus, 1758 Subspecies Salmo trutta fario Salmo trutta trutta The Brown Trout (Salmo trutta fario) and the Sea Trout (Salmo trutta trutta) are fish distinguished chiefly by the fact that the Brown Trout is largely a freshwater fish, while the Sea Trout shows anadromous reproduction, spawning... Binomial name Thymallus arcticus (Pallas, 1776) The Arctic grayling (Thymallus arcticus) is a species of freshwater fish in the salmon family (family Salmonidae) of order Salmoniformes. ... This page tabulates susceptibility of various salmonids to whirling disease. ...

Diagnosis

The normally uniform trout cartilage is scarred with lesions in which M. cerebralis spores develop, weakening and deforming the connective tissues.

Moderate or heavy clinical infection of fish with whirling disease can be presumptively diagnosed on the basis of changes in behavior and appearance about 35 to 80 days after initial infection, though "injury or deficiency in dietary tryptophan and ascorbic acid can evoke similar signs," so conclusive diagnosis may require finding myxospores in the fish's cartilage^[38]. In heavy infections, examining cartilage microscopically may be all that is needed to find spores^[39]. In less severe infections the most common test involves digestion of the cranial cartilage with the proteases pepsin and trypsin (the pepsin-trypsin digest—PTD) before looking for spores. The head and other tissues can be further examined using histopathology to confirm that the location and morphology of the spores matches what is known for M. cerebralis. Serological identification of spores in tissue sections using an antibody raised against the spores is also possible. Parasite identity can also be confirmed using the polymerase chain reaction to amplify the 415 base pair 18S rRNA gene from M. cerebralis^[40]. Fish should be screened at the life stage most susceptible to the parasite. Routine screening using these techniques is carried out in countries where the parasite occurs and in countries like Australia and Canada that are not known to have the parasite but where its introduction could threaten local fish. Download high resolution version (1099x736, 484 KB)A photomicrograph of the histological changes caused by Myxobolus cerebralis infection of salmonid cartilage, stained with Giemsa. ... Download high resolution version (1099x736, 484 KB)A photomicrograph of the histological changes caused by Myxobolus cerebralis infection of salmonid cartilage, stained with Giemsa. ... Tryptophan is an amino acid and essential in human nutrition. ... This article deals with the molecular aspects of ascorbic acid. ... Proteases (proteinases, peptidases or proteolytic enzymes) are enzymes that break peptide bonds between amino acids of proteins. ... This article is in need of attention from an expert on the subject. ... Trypsin(EC 3. ... Histopathology is a field of pathology which specialises in the histologic study of diseased tissue. ... Schematic of antibody binding to an antigen An antibody is a protein used by the immune system to identify and neutralize foreign objects like bacteria and viruses. ... Polymerase chain reaction (PCR) is a molecular biology technique for enzymatically replicating DNA without using a living organism, such as E. coli or yeast. ... This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ...

Impact

M. cerebralis has been reported in Germany (1893), Italy (1954), USSR (1955), including Sakhalin Island (1960), USA (1958), Bulgaria (1960), Yugoslavia (1960), Sweden (1966), South Africa (1966), Scotland (1968), New Zealand (1971), Ecuador (1971), Norway (1971), Colombia (1972), Lebanon (1973), Ireland (1974), Spain (1981) and England (1981)

Although originally a mild pathogen of Salmo trutta in central Europe and other salmonids in north east Asia, the spread of the Rainbow trout (Oncorhynchus mykiss) has greatly increased the impact of this parasite. Having no innate immunity to M. cerebralis, rainbow trout are particularly susceptible, and can release so many spores that even more resistant species in the same area, like S. trutta, can become overloaded with parasites and incur 80%–90% mortalities. Where M. cerebralis has become well-established, it has caused decline or even elimination of whole cohorts of fish^[41][42]. Download high resolution version (1357x628, 47 KB)Distribution of the fish parasite as reported in Hoffman, G. L. 1990. ... Download high resolution version (1357x628, 47 KB)Distribution of the fish parasite as reported in Hoffman, G. L. 1990. ... Location of Sakhalin in the Western Pacific. ... Yugoslavia (Jugoslavija in all south Slavic languages, in Serbian and Macedonian Cyrillic Југославија) is a term used for three separate but successive political entities that existed during most of the 20th century on the Balkan Peninsula in Europe. ... Motto: Nemo me impune lacessit (English: No one provokes me with impunity) Scotlands location within Europe Scotlands location within the United Kingdom Languages English, Gaelic, Scots Capital Edinburgh Largest city Glasgow First Minister Jack McConnell Area - Total - % water Ranked 2nd UK 78,782 km² 1. ... Royal motto (French): Dieu et mon droit (Translated: God and my right) Englands location (dark green) within the United Kingdom (light green), with the Republic of Ireland (blue) to its west Languages None official English de facto Capital None official London de facto Largest city London Area – Total Ranked... Binomial name Salmo trutta Linnaeus, 1758 Subspecies Salmo trutta fario Salmo trutta trutta The Brown Trout (Salmo trutta fario) and the Sea Trout (Salmo trutta trutta) are fish distinguished chiefly by the fact that the Brown Trout is largely a freshwater fish, while the Sea Trout shows anadromous reproduction, spawning... Binomial name Oncorhynchus mykiss Walbaum, 1792 The rainbow trout (Oncorhynchus mykiss, formerly Salmo iridia) is a single species of trout native to the Pacific Ocean and in North American rivers and lakes west of the Rocky Mountains. ...

Impact in Europe

The impact of M. cerebralis in Europe is somewhat lessened by the fact that the species is endemic to this region, giving native fish stocks a degree of immunity. Rainbow trout, the most susceptible species to this parasite, are not native to Europe; successfully reproducing feral populations are rare, so there are few wild rainbow trout that are young enough to be susceptible to infection. On the other hand, they are widely reared for restocking sport-fishing waters and for aquaculture, where this parasite has its greatest impact. Hatching and rearing methods designed to prevent infection of Rainbow trout fry have proved successful in Europe. These techniques include hatching eggs in spore-free water and rearing fry to the "ossification" stage in tanks or raceways. These methods give particular attention to the quality of water sources in order to guard against spore introduction during water exchanges^[43]. Fry are moved to earthen ponds only when they are considered to be clinically resistant to the parasite, after skeletal ossification occurs^[44]. Fish stocks are subpopulations of a particular species of fish, for which intrinsic parameters (growth, recruitment, mortality and fishing mortality) are the only significant factors in determining population dynamics, while extrinsic factors (immigration and emmigration) are considered to be insignificant. ... In a medical sense, immunity is a state of having sufficient biological defenses to avoid infection, disease, or other unwanted biological invasion. ... Binomial name Oncorhynchus mykiss Walbaum, 1792 The rainbow trout (Oncorhynchus mykiss, formerly Salmo iridia) is a single species of trout native to the Pacific Ocean and in North American rivers and lakes west of the Rocky Mountains. ... Wyoming Mustang (feral) courtesy of U.S. BLM Wild Horse and Burro Program A feral animal or plant is one that has escaped from domestication and returned, partly or wholly, to its wild state. ... Fishing is the activity of hunting for fish. ... The examples and perspective in this article may not represent a worldwide view. ...

Impact in New Zealand

M. cerebralis was first found in New Zealand in 1971. The parasite has only been found in rivers in the South Island, away from the most important aquaculture sites. Additionally, salmonid species commercially aquacultured in New Zealand have low susceptibility to whirling disease, and the parasite has also not been shown to affect native salmonids^[45]. An important indirect effect of the parasites presence is quarantine restriction placed on exports of salmon products to Australia. Quarantine, a medical term (from Italian: quaranta giorni, forty days) is the act of keeping people or animals separated for a period of time before, for instance, allowing them to enter another country. ...

Impact in the United States

M. cerebralis has been reported in nearly two dozen (green) states in the United States according to the Whirling Disease Initiative

M. cerebralis was first recorded in North America in 1956 in Pennsylvania, having been introduced via infected trout imported from Europe, and has spread steadily south and westwards^[46]. Until the 1990s, whirling disease was considered a manageable problem affecting rainbow trout in hatcheries. However, it has recently become established in natural waters of the Rocky Mountain states (Colorado, Wyoming, Utah, Montana, Idaho, New Mexico) where it is causing heavy mortalities in several sportfishing rivers. Some streams in the western United States have lost 90% of their trout^[47]. In addition, whirling disease threatens recreational fishing, which is important for the tourism industry, a key component of the economies of some U.S. western states. For example, "the Montana Whirling Disease Task Force estimated that trout fishing generated US $300,000,000 in recreational expenditures in Montana alone"^[48]. Making matters worse, some of the fishes that M. cerebralis infects (bull trout, cutthroat trout, and steelhead) are already threatened or endangered, and the parasite could worsen their already precarious situations^[49]. For reasons that are poorly understood, but probably have to do with environmental conditions, the impact on infected fish has been greatest in Colorado and Montana and least in California, Michigan, and New York.^[50] Image File history File links Download high resolution version (1032x698, 11 KB)Range of Myxobolus cerebralis in the US. Its modified from a U.S. government map so its public domain. ... Image File history File links Download high resolution version (1032x698, 11 KB)Range of Myxobolus cerebralis in the US. Its modified from a U.S. government map so its public domain. ... Official language(s) None Capital Largest city Harrisburg Philadelphia Area  Ranked 33rd  - Total 46,055 sq mi  (119,283 km²)  - Width 160 miles (255 km)  - Length 280 miles (455 km)  - % water 2. ... Official language(s) English Capital Denver Largest city Denver Area  - Total   - Width   - Length    - % water  - Latitude  - Longitude Ranked 8th 104,185 sq mi  269 837 km² 280 miles  451 km 380 miles  612 km 0. ... Official language(s) English Capital Largest city Cheyenne Cheyenne Area  Ranked 10th  - Total 97,872 sq mi  (253,554 km²)  - Width 280 miles (450 km)  - Length 360 miles (580 km)  - % water 0. ... Official language(s) English Capital Largest city Salt Lake City Salt Lake City Area  - Total  - Width  - Length  - % water  - Latitude  - Longitude Ranked 13th 219,887 km² 435 km 565 km 3. ... Official language(s) English Capital Helena Largest city Billings Area  - Total  - Width  - Length  - % water  - Latitude  - Longitude Ranked 4th 381,156 km² 410 km 1,015 km 1 44°26 N to 49° N 104°2 W to 116°2 W Population  - Total (2000)  - Density Ranked 44th 1,087,340 2. ... Official language(s) None Capital Largest city Boise Boise Area  Ranked 14th  - Total 83,642 sq. ... Official language(s) None; English and Spanish de facto Capital Largest city Santa Fe Albuquerque Area  Ranked 5th  - Total 121,665 sq mi  (315,194 km²)  - Width 342 miles (550 km)  - Length 370 miles (595 km)  - % water 0. ... Official language(s) English Capital Helena Largest city Billings Area  - Total  - Width  - Length  - % water  - Latitude  - Longitude Ranked 4th 381,156 km² 410 km 1,015 km 1 44°26 N to 49° N 104°2 W to 116°2 W Population  - Total (2000)  - Density Ranked 44th 1,087,340 2. ... Binomial name Salvelinus confluentus Suckley, 1859 The bull trout (Salvelinus confluentus) is a char of the family Salmonidae. ... Binomial name Oncorhynchus clarki (Richardson, 1836) Subspecies See text. ... Binomial name Oncorhynchus mykiss Walbaum, 1792 The Rainbow Trout (Oncorhynchus mykiss), also called steelhead trout, is a single species of trout native to the Pacific Ocean and in North American rivers and lakes west of the Rocky Mountains. ... The endangered Sea Otter An endangered species is a population of organisms (frequently but not always a taxonomic species) which is either (a) so few in number or (b) threatened by changing environmental or predation parameters that it is at risk of becoming extinct. ... Official language(s) English Capital Largest city Sacramento Los Angeles Area  - Total   - Width   - Length    - % water  - Latitude  - Longitude Ranked 3rd 158,302 sq mi  410,000 km² 250 miles  400 km 770 miles  1,240 km 4. ... Official language(s) None (English, de-facto) Capital Largest city Lansing Detroit Area  - Total   - Width   - Length    - % water  - Latitude  - Longitude Ranked 10th 102,384 sq mi  265,172 km² 239 miles  385 km 491 miles  790 km 41. ... Official language(s) None, English de facto Capital Largest city Albany New York City Area  Ranked 27th  - Total 54,520 sq mi  (141,205 km²)  - Width 285 miles (455 km)  - Length 330 miles (530 km)  - % water 13. ...

Prevention and control

Some biologists have attempted to disarm triactinomyxon spores by making them fire prematurely. In the laboratory, only extreme acidity or basicity, moderate to high concentrations of salts, or electrical current caused premature filament discharge; neurochemicals, cnidarian chemosensitizers, and trout mucous were ineffective^[51], as were anesthetized or dead fish^[52]. If spores could be disarmed, they would be unable to infect fish, but it is unclear whether any of the methods that worked in the laboratory could be employed in the wild. Acidity is a controversial novelette written for the popular South Asian website Chowk. ... The common (Arrhenius) definition of a base is a chemical compound that either donates hydroxide ions or absorbs hydrogen ions when dissolved in water. ...

Some strains of fish are more resistant than others, even within species^[53]; using resistant strains may help reduce the incidence and severity of whirling disease in aquaculture. There is also some circumstantial evidence that fish populations can develop resistance to the disease over time^[54]. Additionally, aquaculturists may avoid M. cerebralis infections by not using earthen ponds for raising young fish; this keeps them away from possibly infected tubificids and makes it easier to eliminate spores and oligochaetes through filtration, chlorination, and ultraviolet bombardment^[55]. To minimise tubificid population techniques include periodic disinfection of the hatchery or aquaculture ponds and the rearing of small trout indoors in pathogen-free water. Smooth-faced concrete or plastic-lined raceways that are kept clean and free of contaminated water keep aquaculture facilities free of the disease^[56]. The examples and perspective in this article may not represent a worldwide view. ...

Lastly, some drugs such as furazolidone, furoxone, benomyl, fumagillin, proguanil and clamoxyquine have been shown to impede spore development, which reduces infection rates^[57]. For example, one study showed that feeding Fumagillin to Oncorhynchus mykiss reduced the number of infected fish from between 73% and 100% to between 10% and 20%^[58]. Unfortunately, this treatment is considered unsuitable for wild trout populations^[59], and no drug treatment has ever been shown to be effective in the studies required for United States Food and Drug Administration approval^[60]. Furazolidone (also marketed as Furoxone) is an antibiotic used to treat diarrhea and enteritis caused by bacteria or protozoan infections. ... Furazolidone (also marketed as Furoxone) is an antibiotic used to treat diarrhea and enteritis caused by bacteria or protozoan infections. ... Benomyl (also marketed as Benlate) is a fungicide which was introduced in 1968 by Du Pont. ... Fumagillin is an antibiotic originally used against fungal Nosema apis infections in honeybees. ... Proguanil (proguanil hydrochloride) is a prophylactic antimalarial drug, which works by stopping the malaria parasite, Plasmodium falciparum, from reproducing once it is in the red blood cells. ... Clamoxyquine (previously known as Clamoxyquin, and Clamoxyquin pamoate), is an antiamebic and antidiarrheal drug. ... Binomial name Oncorhynchus mykiss Walbaum, 1792 The Rainbow Trout (Oncorhynchus mykiss), also called steelhead trout, is a single species of trout native to the Pacific Ocean and in North American rivers and lakes west of the Rocky Mountains. ... This article or section is in need of attention from an expert on the subject. ...

Recreational and sports fishers can help to prevent the spread of the parasite in a number of ways. Cleaning fishing equipment between fishing trips and never transporting fish from one body of water to another should protect against cross contamination of waterways. Spores are particularly persistent in felt soled wading shoes, which can be treated with 10% chlorine bleach and water for at least 15 minutes and then rinsed thoroughly. Fish bones or entrails should never be disposed of in any body of water, since spores from the carcass will be released into the waterway. Salmon and trout should not be used as bait. Commercial chlorine bleach To bleach something is to remove or lighten its color; a bleach is a chemical that can produce these effects, often via oxidization. ... Grays illustration of a human femur, a typically recognized bone. ... Bait has several different meanings: Bait (dogs) - using dogs to worry or torment a chained or confined animal Bait (fish) - food to lure fish Baitware - limited or defective computer software Bait car - vehicle rigged by the police to catch auto thieves Bait and switch - a form of fraud The Bait...

Notes

1. ↑  Bartholomew, J.L. and Reno, P.W. (2002). The history and dissemination of whirling disease. American Fisheries Society Symposium 29: 3–24.
   
2. ↑  Markiw, M.E. (1992). Salmonid Whirling didease. Fish and Wildlife Leaflet 17: 1–3. [61]
   
3. ↑  Gilbert, M. A. & Granath, W.O. Jr. (2003). Whirling disease and salmonid fish: life cycle, biology, and disease. Journal of Parasitology 89: 658–667.
   
4. ↑  Bartholomew, J.L. and Reno, P.W. (2002). The history and dissemination of whirling disease. American Fisheries Society Symposium 29: 3–24.
   
5. ↑  Kent, M. L., Margolis, L. & Corliss, J.O. (1994). The demise of a class of protists: taxonomic and nomenclatural revisions proposed for the protist phylum Myxozoa Grasse, 1970. Canadian Journal of Zoology 508: 932–937.
   
6. ↑  Hedrick, R. P. & El–Matbouli, M. (2002). Recent advances with taxonomy, life cycle, and development of Myxobolus cerebralis in the fish and oligochaete hosts. American Fisheries Society Symposium 29: 45–53.
   
7. ↑  Monteiro, A. S., Okamura, B., and P. W. H. Holland. (2002). Orphan worm finds a home: Buddenbrockia is a Myxozoan. Molecular Biology and Evolution 19: 968–971. [62]
   
8. ↑  Hedrick, R. P. & El–Matbouli, M. (2002). Recent advances with taxonomy, life cycle, and development of Myxobolus cerebralis in the fish and oligochaete hosts. American Fisheries Society Symposium 29: 45–53.
   
9. ↑  Markiw, M.E. (1992). Salmonid Whirling didease. Fish and Wildlife Leaflet 17: 1–3. [63]
   
10. ↑  Markiw, M.E. (1989). Portals of entry for salmonid whirling disease in rainbow trout. Diseases of Aquatic Organisms 6: 6-10.
    
11. ↑  Hedrick, R. P. & El–Matbouli, M. (2002). Recent advances with taxonomy, life cycle, and development of Myxobolus cerebralis in the fish and oligochaete hosts. American Fisheries Society Symposium 29: 45–53.
    
12. ↑  Markiw, M.E. (1992). Salmonid Whirling didease. Fish and Wildlife Leaflet 17: 1–3. [64]
    
13. ↑  Markiw, M.E. (1992). Salmonid Whirling didease. Fish and Wildlife Leaflet 17: 1–3. [65]
    
14. ↑  Gilbert, M. A. & Granath, W.O. Jr. (2003). Whirling disease and salmonid fish: life cycle, biology, and disease. Journal of Parasitology 89: 658–667.
    
15. ↑  El-Matbouli, M., and Hoffmann, R.W. (1998). Light and electron microscopic studies on the chronological development of Myxobolus cerebralis to the Actinosporean stage in Tubifex Tubifes. International Journal For Parasitology 28: 195–217.
    
16. ↑  Hedrick, R. P. & El–Matbouli, M. (2002). Recent advances with taxonomy, life cycle, and development of Myxobolus cerebralis in the fish and oligochaete hosts. American Fisheries Society Symposium 29: 45–53.
    
17. ↑  Hedrick, R. P. & El–Matbouli, M. (2002). Recent advances with taxonomy, life cycle, and development of Myxobolus cerebralis in the fish and oligochaete hosts. American Fisheries Society Symposium 29: 45–53.
    
18. ↑  El-Matbouli, M., and Hoffmann, R.W. (1998). Light and electron microscopic studies on the chronological development of Myxobolus cerebralis to the Actinosporean stage in Tubifex Tubifes. International Journal For Parasitology 28: 195–217.
    
19. ↑  Hedrick, R. P. & El–Matbouli, M. (2002). Recent advances with taxonomy, life cycle, and development of Myxobolus cerebralis in the fish and oligochaete hosts. American Fisheries Society Symposium 29: 45–53.
    
20. ↑  Hedrick, R. P. & El–Matbouli, M. (2002). Recent advances with taxonomy, life cycle, and development of Myxobolus cerebralis in the fish and oligochaete hosts. American Fisheries Society Symposium 29: 45–53.
    
21. ↑  Nehring, R. B. Thompson, K. G. Taurman, K. A. & Shuler, D.L. (2002). Laboratory studies indicating that living brown trout Salmo trutta expel viable Myxobolus cerebralis myxospores. American Fisheries Society Symposium 29: 125–134.
    
22. ↑  El-Matbouli, M., and Hoffmann, R.W. (1991). Effects of freezing, aging, and passage through the alimentary canal of predatory animals on the viability of Myxobolus cerebralis spores. Journal of Aquatic Animal Health 3: 260–262.
    
23. ↑  Markiw, M.E. (1992). Experimentally induced whirling disease. II. Determination of longevity of the infective triactinomyxon stage of Myxobolus cerebralis by vital staining. Journal of Aquatic Animal Health 4 (1): 44–47.
    
24. ↑  Lom, J. & Dyková, I. (1992). Protozoan Parasites of Fishes, Elsevier, Amsterdam. ISBN 0444894349.
    
25. ↑  Hedrick, R. P. & El–Matbouli, M. (2002). Recent advances with taxonomy, life cycle, and development of Myxobolus cerebralis in the fish and oligochaete hosts. American Fisheries Society Symposium 29: 45–53.
    
26. ↑  Markiw, M.E. (1992). Salmonid Whirling didease. Fish and Wildlife Leaflet 17: 1–3. [66]
    
27. ↑  Gilbert, M. A. & Granath, W.O. Jr. (2003). Whirling disease and salmonid fish: life cycle, biology, and disease. Journal of Parasitology 89: 658–667.
    
28. ↑  Gilbert, M. A. & Granath, W.O. Jr. (2003). Whirling disease and salmonid fish: life cycle, biology, and disease. Journal of Parasitology 89: 658–667.
    
29. ↑  Hedrick, R. P. & El–Matbouli, M. (2002). Recent advances with taxonomy, life cycle, and development of Myxobolus cerebralis in the fish and oligochaete hosts. American Fisheries Society Symposium 29: 45–53.
    
30. ↑  Gilbert, M. A. & Granath, W.O. Jr. (2003). Whirling disease and salmonid fish: life cycle, biology, and disease. Journal of Parasitology 89: 658–667.
    
31. ↑  Gilbert, M. A. & Granath, W.O. Jr. (2003). Whirling disease and salmonid fish: life cycle, biology, and disease. Journal of Parasitology 89: 658–667.
    
32. ↑  Vincent, E. R. (2002). Relative susceptibility of various salmonids to whirling disease with emphasis on rainbow and cutthroat trout.. American Fisheries Society Symposium 29: 109–115.
    
33. ↑  Halliday, M.M. (1976). The Biology Of Myxosoma cerebralis: The Causative Organism Of Whirling Disease Of Salmonids. Journal of Fish Biology 9: 339–357.
    
34. ↑  Gilbert, M. A. & Granath, W.O. Jr. (2003). Whirling disease and salmonid fish: life cycle, biology, and disease. Journal of Parasitology 89: 658–667.
    
35. ↑  Vincent, E. R. (2002). Relative susceptibility of various salmonids to whirling disease with emphasis on rainbow and cutthroat trout.. American Fisheries Society Symposium 29: 109–115.
    
36. ↑  Hoffmann, G. (1962). Whirling Disease Of Trout. U.S. Department Of The Interior, Fishery Leaflet 508: 1–3.
    
37. ↑  Gilbert, M. A. & Granath, W.O. Jr. (2003). Whirling disease and salmonid fish: life cycle, biology, and disease. Journal of Parasitology 89: 658–667.
    
38. ↑  Markiw, M.E. (1992). Salmonid Whirling didease. Fish and Wildlife Leaflet 17: 1–3. [67]
    
39. ↑ Markiw, M.E. (1992). Salmonid Whirling didease. Fish and Wildlife Leaflet 17: 1–3. [68]
    
40. ↑  Andree, K.B., MacConnell, E. and Hedrick, R.P. (1998). A nested polymerase chain reaction for the detection of genomic DNA of Myxobolus cerebralis in rainbow trout Oncorhynchus mykiss. Diseases of Aquatic Organisms 34: 145–54.
    
41. ↑  Nehring, R.B. (1996). Whirling Disease In Feral Trout Populations In Colorado. In E.P. Bergersen And B.A.Knoph (eds.), Proceedings: Whirling Disease Workshop––where Do We Go From Here? Colorado Cooperative Fish And Wildlife Research Unit, Fort Collins.: pp.159.
    
42. ↑  Vincent, E.R. (1996). Whirling Disease—the Montana Experience, Madison River.. In, E.P. Bergersen And B.A.Knoph (eds.), Proceedings: Whirling Disease Workshop—where Do We Go From Here? Colorado Cooperative Fish And Wildlife Research Unit, Fort Collins.: pp.159.
    
43. ↑  Ghittino, P. (1970). Present Status Of Whirling Disease In Italian Trout Farms. Riv. It. Piscic. Ittiopat 5: 89–92.
    
44. ↑  Halliday, M.M. (1976). The Biology Of Myxosoma cerebralis: The Causative Organism Of Whirling Disease Of Salmonids. Journal of Fish Biology 9: 339–357.
    
45. ↑  Stone M A B, MacDiarmid S C, Pharo H J. (1997). Import health risk analysis: salmonids for human consumption. Ministry of Agriculture Regulatory Authority, New Zealand.[69]
    
46. ↑  Bergersen, E.P., and Anderson, D.E. (1997). The distribution and spread of Myxobolus cerebralis in the United States. Fisheries 22 (8): 6–7.
    
47. ↑  Tennyson, J. Anacker, T. & Higgins, S. (January 13, 1997). Scientific breakthrough helps combat trout disease. U.S. Fish and Wildlife Service Whirling Disease Foundation News Release.[70]
    
48. ↑  Gilbert, M. A. & Granath, W.O. Jr. (2003). Whirling disease and salmonid fish: life cycle, biology, and disease. Journal of Parasitology 89: 658–667.
    
49. ↑  Gilbert, M. A. & Granath, W.O. Jr. (2003). Whirling disease and salmonid fish: life cycle, biology, and disease. Journal of Parasitology 89: 658–667.
    
50. ↑  Wisconsin Department of Agriculture, Trade and Consumer Protection. Division of Animal Health. (October 2001). "Fish Health Advisory: Whirling Disease in Trout." [71] (.pdf).
    
51. ↑  Wagner, E. J. Cannon, Q. Smith, M. Hillyard, R. & Arndt, R. (2002). Extrusion of Polar Filaments of the Myxobolus cerebralis Triactinomyxon by salts, electricity, and other agents. American Fisheries Society Symposium 29: 61–76.
    
52. ↑  El-Matbouli, M., Hoffman, R.W., Shoel, H., McDowell, T. S., & Hedrick, R.P. (1999). Whirling disease: host specificity and interaction between the actinosporean stage of Myxobolus cerebralis and rainbow trout (Oncorhynchus mykiss) cartilage. Diseases of Aquatic Organisms 35: 1–12.
    
53. ↑  Vincent, E. R. (2002). Relative susceptibility of various salmonids to whirling disease with emphasis on rainbow and cutthroat trout.. American Fisheries Society Symposium 29: 109–115.
    
54. ↑  Whirling Disease Foundation News. July, 2003. Research on whirling disease resistant rainbow trout.[72]
    
55. ↑  Markiw, M.E. (1992). Salmonid Whirling didease. Fish and Wildlife Leaflet 17: 1–3. [73]
    
56. ↑  Markiw, M.E. (1992). Salmonid Whirling didease. Fish and Wildlife Leaflet 17: 1–3. [74]
    
57. ↑  Markiw, M.E. (1992). Salmonid Whirling didease. Fish and Wildlife Leaflet 17: 1–3. [75]
    
58. ↑  El-Matbouli, M., and Hoffmann, R.W. (1991). Effects of freezing, aging, and passage through the alimentary canal of predatory animals on the viability of Myxobolus cerebralis spores. Journal of Aquatic Animal Health 3: 260–262.
    
59. ↑  El-Matbouli, M., and Hoffmann, R.W. (1998). Light and electron microscopic studies on the chronological development of Myxobolus cerebralis to the Actinosporean stage in Tubifex Tubifes. International Journal For Parasitology 28: 195–217.
    
60. ↑  Gilbert, M. A. & Granath, W.O. Jr. (2003). Whirling disease and salmonid fish: life cycle, biology, and disease. Journal of Parasitology 89: 658–667.
    

See also

• Ceratomyxa shasta - another pathogenic myxosporean parasite of salmonids.
• Infectious salmon anemia (ISA) - a viral infection of Atlantic Salmon.
• Kudoa thyrsites - a myxosporean parasite of many species, which causes fish tissues to liquefy on death.
• Tetracapsuloides bryosalmonae - the enigmatic myxosporean which causes "Proliferative Kidney Disease" in salmonids.

Binomial name Ceratomyxa shasta (Noble, 1950) Ceratomyxa shasta is a myxosporean parasite that infects salmonid fish on the Pacific coast of North America. ... Infectious salmon anemia or anaemia (ISA) is a viral disease of Atlantic Salmon (Salmo salar) which affect fish farms in Canada, Norway and Scotland, causing severe losses to infected farms. ... Binomial name Kudoa thrysites (Gilchrist, 1924) Kudoa thrysites is a myxosporean parasite of marine fishes. ... Binomial name Tetracapsuloides bryosalmonae Canning , 1999 Synonyms Tetracapsuloides bryosalmonae is a myxosporean parasite of salmonid fishes, which causes Proliferative kidney disease (PKD), one of the most serious parasitic diseases of salmonid populations in Europe and North America[1], which causes losses of up to 90% in infected populations. ...

External links

• Report of the World Trade Organization on Australian restrictions on salmon imports
• The Whirling Disease Foundation
• The Whirling Disease Initiative

   

Image File history File links LinkFA-star. ...