Cod and related species in the family Gadidae are susceptible to a variety of diseases and parasites.
Cod and related species in the family Gadidae are susceptible to a variety of diseases and parasites.
Lernaeocera branchialis , the "cod worm", is a copepod that infects gadoids. The first host used by cod worm is a flatfish or lumpsucker, which it captures with grasping hooks at the front of its body. It penetrates the lumpsucker with a thin filament, which it uses to suck the host's blood. The nourished cod worm then mates with another one on the lumpsucker. [1] [2] The female worm, with her now-fertilized eggs, then finds a cod, or a cod-like fish, such as a haddock or whiting. There, the worm clings to the gills while it metamorphoses into a plump, sinusoidal, worm-like body, with a coiled mass of egg strings at the rear. The front part of the worm's body penetrates the body of the cod until it enters the rear bulb of the host's heart. There, firmly rooted in the cod's circulatory system, the front part of the parasite develops like the branches of a tree, reaching into the main artery. In this way, the worm extracts nutrients from the cod's blood, remaining safely tucked beneath the cod's gill cover until it releases a new generation of offspring into the water. [1] [2]
Atlantic cod act as intermediate, paratenic, or definitive hosts to a large number of parasite species; 107 taxa are listed by Hemmingsen and MacKenzie (2001) [3] with seven new records by Perdiguero-Alonso et al. (2008). [3] The predominant groups of cod parasites in the northeast Atlantic were trematodes (19 species) and nematodes (13 species), including larval anisakids, which comprised 58.2% of the total number of individuals. [3] Parasites of Atlantic cod include copepods, digeneans, monogeneans, acanthocephalans, cestodes, nematodes, myxozoans and protozoans: [3]
Trematoda – metacercariae
Trematoda – adult
Cestoda – larval forms
Cestoda – adult
Nematoda – larval forms
Nematoda – adults
Acanthocephala – post-cystacanths
Acanthocephala – adults
Hirudinea – adults
Copepoda - larval forms
Copepoda – adults
Cod is the common name for the demersal fish genus Gadus, belonging to the family Gadidae. Cod is also used as part of the common name for a number of other fish species, and one species that belongs to genus Gadus is commonly not called cod.
The Atlantic cod is a benthopelagic fish of the family Gadidae, widely consumed by humans. It is also commercially known as cod or codling. Dry cod may be prepared as unsalted stockfish, and as cured salt cod or clipfish.
Acanthocephala is a phylum of parasitic worms known as acanthocephalans, thorny-headed worms, or spiny-headed worms, characterized by the presence of an eversible proboscis, armed with spines, which it uses to pierce and hold the gut wall of its host. Acanthocephalans have complex life cycles, involving at least two hosts, which may include invertebrates, fish, amphibians, birds, and mammals. About 1420 species have been described.
The haddock is a saltwater ray-finned fish from the family Gadidae, the true cods. It is the only species in the monotypic genus Melanogrammus. It is found in the North Atlantic Ocean and associated seas, where it is an important species for fisheries, especially in northern Europe, where it is marketed fresh, frozen and smoked; smoked varieties include the Finnan haddie and the Arbroath smokie.
Merlangius merlangus, commonly known as Whiting or merling, is an important food fish in the eastern North Atlantic Ocean and the northern Mediterranean, western Baltic, and Black Sea. In Anglophonic countries outside the Whiting's natural range, the name "whiting" has been applied to various other species of fish.
The thorny-headed worm family Polymorphidae contains endoparasites which as adults feed mainly in fish and aquatic birds. When this taxon was erected by Meyer in 1931, a subfamily Polymorphinae was established in it. As the Polymorphidae as presently understood would then be monotypic, with no basal genera outside the Polymorphinae, the proposed subfamily is redundant for the time being and therefore most modern treatments simply omit it. Polymorphus minutus is an economically significant parasite in goose and duck farming.
Acartia hudsonica is a species of marine copepod belonging to the family Acartiidae. Acartia hudsonica is a coastal, cold water species that can be found along the northwest Atlantic coast.
Echinorhynchidae is a family of acanthocephalan parasitic worms from the order Echinorhynchida. The adult worms live in the intestines of fishes, amphibians and reptiles. The family contains the following genera, organised by subfamily.
Caligus curtus is a sea louse species. It is a parasite of the Atlantic cod.
Lernaeocera branchialis, sometimes called cod worm, is a parasite of marine fish, found mainly in the North Atlantic. It is a marine copepod which starts life as a small pelagic crustacean larva. It is among the largest of copepods, ranging in size from 2 to 3 millimetres when it matures as a copepodid larva to more than 40 mm as a sessile adult.
Pennella is a genus of large copepods which are common parasites of large pelagic fishes. They begin their life cycle as a series of free-swimming planktonic larvae. The females metamorphose into a parasitic stage when they attach to a host and enter into its skin. The males are free swimming. Due to their large size and mesoparasitic life history there have been a number of studies of Pennella, the members of which are among the largest of the parasitic Copepoda. All species are found as adults buried into the flesh of marine bony fish, except for a single species, Pennella balaenopterae which can be found in the muscles and blubber of cetaceans and occasionally other marine mammals, and is the largest species of copepod.
Loma morhua, also known as Loma branchialis, is a species of microsporidian parasite, infecting fish. It forms xenoparasitic complexes of the cell-hypertrophy tumour type, and is found in the gills of the Atlantic cod Gadus morhua. It is apansporoblastic, unikaryotic, disporoblastic and undergoes partial development in parasitophorous vacuoles, while lacking plasmodial stages. It produces one or two spores in a vacuole, having tubules in the parasitophorous vacuoles.
Lethrinus rubrioperculatus, common names the spotcheek emperor, red-eared emperor, red-ears, red-edged emperor, scarlet-cheek emperor, and spot cheek emperor, is a species of emperor fish.
Gadimyxa atlantica is a species of parasitic myxozoan. Together with G. arctica and G. sphaerica, they infect Gadus morhua and Arctogadus glacialis by developing coelozoically in bisporic plasmodia in their urinary systems. These 3 species' spores exhibit two morphological forms: wide and subspherical, being both types bilaterally symmetrical along the suture line. The wide spores have a mean width ranging from 7.5-10μm, respectively, while the subspherical ones range from 5.3-8μm in mean width. The subspherical forms of Gadimyxa are similar to Ortholinea, differing in the development of the spores and in the arrangement of the polar capsules. Polychaetes Spirorbisspecies act as invertebrate hosts of G. atlantica.
Gadimyxa sphaerica is a species of parasitic myxozoan. Together with G. arctica and G. atlantica, they infect Gadus morhua and Arctogadus glacialis by developing coelozoically in bisporic plasmodia in their urinary systems. These 3 species' spores exhibit two morphological forms: wide and subspherical, being both types bilaterally symmetrical along the suture line. The wide spores have a mean width ranging from 7.5-10μm, respectively, while the subspherical ones range from 5.3-8μm in mean width. The subspherical forms of Gadimyxa are similar to Ortholinea, differing in the development of the spores and in the arrangement of the polar capsules.
Gadimyxa arctica is a species of parasitic myxozoan. Together with G. atlantica and G. sphaerica, they infect Gadus morhua and Arctogadus glacialis by developing coelozoically in bisporic plasmodia in their urinary systems. These 3 species' spores exhibit two morphological forms: wide and subspherical, being both types bilaterally symmetrical along the suture line. The wide spores have a mean width ranging from 7.5-10μm, respectively, while the subspherical ones range from 5.3-8μm in mean width. The subspherical forms of Gadimyxa are similar to Ortholinea, differing in the development of the spores and in the arrangement of the polar capsules.
Cucullanus is a genus of parasitic nematodes. The genus includes more than 100 species.
Neoandracantha is a genus of parasitic worms from the phylum Acanthocephala. The genus was created in 2017 by Amin & Heckmann for the single species Neoandracantha peruensis.
Lernaeenicus sprattae is a species of copepod in the family Pennellidae. It is a parasite of the European sprat and certain other fish and is sometimes known as the sprat eye-maggot.
Jean-Lou Justine, French parasitologist and zoologist, is a professor at the National Museum of Natural History in Paris, France, and a specialist of fish parasites and invasive land planarians.
This article incorporates CC-BY-2.0 text from the reference: Perdiguero-Alonso D., Montero F. E., Raga J. A. & Kostadinova A. (2008). "Composition and structure of the parasite faunas of cod, Gadus morhua L. (Teleostei: Gadidae), in the North East Atlantic". Parasites & Vectors 2008, 1: 23. doi:10.1186/1756-3305-1-23
