The Fasciola hepatica, commonly known as the liver fluke, is a parasitic flatworm of the class Trematoda, phylum Platyhelminthes that infects the hepatic bile ducts of sheep and cattle, sometimes also humans, causing fascioliasis also known as fasciolosis. Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms. ... 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) Myxozoa (slime animals) Superphylum Deuterostomia (blastopore becomes anus) Chordata (vertebrates, etc. ... Classes Monogenea Trematoda Cestoda Turbellaria The flatworms (Platyhelminthes, Greek platy: flat; helminth: worm) are a phylum of relatively simple soft-bodied invertebrate animals. ... Subclasses Aspidogastrea Digenea The Trematoda is a class within the phylum Platyhelminthes, which contains two groups of parasitic worms. ... Orders within the Digenea Strigeidida Azygiida Echinostomida Plagiorchiida Opisthorchiida The digenea (Gr. ... Liver flukes are a polyphyletic group of a trematodes (a kind of flatworm). ... In biology, binomial nomenclature is the formal method of naming species. ... Parasitism is an interaction between two organisms, in which one organism (the parasite) benefits and the other (the host) is harmed, though usually without killing the host. ... Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ... Subclasses Aspidogastrea Digenea The Trematoda is a class within the phylum Platyhelminthes, which contains two groups of parasitic worms. ... Phylum (plural: phyla) is a taxon used in the classification of life, adopted from the Greek phylai the clan-based voting groups in Greek city-states. ... Classes Monogenea Trematoda Cestoda Turbellaria The flatworms (Platyhelminthes, Greek platy: flat; helminth: worm) are a phylum of relatively simple soft-bodied invertebrate animals. ... The liver is an organ in vertebrates including humans. ... Bile (or gall) is a bitter, greenish-yellow alkaline fluid secreted by the liver of most vertebrates. ... Species See text. ... Binomial name Bos taurus Linnaeus, 1758 Cattle (called cows in vernacular and contemporary usage, kine or kyne in pre-modern English, or kye as the Scots plural of cou) are domesticated ungulates, a member of the subfamily Bovinae of the family Bovidae. ... Trinomial name Homo sapiens sapiens Linnaeus, 1758 Humans, or human beings, are bipedal primates belonging to the mammalian species Homo sapiens (Latin for wise man or knowing man) under the family Hominidae (known as the great apes). ... Fascioliasis is caused by the trematodes Fasciola hepatica (the sheep liver fluke) and Fasciola gigantica, parasites of herbivores that can infect humans accidentally. ... Fascioliasis is caused by the trematodes Fasciola hepatica (the sheep liver fluke) and Fasciola gigantica, parasites of herbivores that can infect humans accidentally. ...

Life Cycle

In order to complete its life cycle, F. hepatica requires an intermediate host. Its intermediate host is a snail, such as Lymnaea truncatula, in which the parasite can reproduce asexually. From the snail, minute cercariae emerge and swim through free-lying pools of water in pasture, and encyst as metacercariae on near-by vegetation. From here, the metacercariae are ingested by the ruminant, or in some cases, by humans eating un-cooked foods such as water-cress. Contact with low pH in the stomach causes the early immature juvenile to begin the process of excystment. In the duodenum, the parasite breaks free of the metacercariae and burrows throught the intestinal lining into the peritoneal cavity. The newly excysted juveile does not feed at this stage, but once it finds the liver parenchyma after a period of days, feeding will commence. This immature stage in the liver tissue is the pathogenic stage, causing the anaemia and clinical signs sometimes observed in infected animals. The parasite browses on liver tissue for a period of up to 5-6 weeks and eventually finds its way to the bile duct where it matures into an adult and begins to produce eggs. A number of up to 25,000 eggs per day per fluke can be produced, and in a light infection, up to 500,000 eggs per day can be deposited onto pasture by a single sheep. In parasitology, an intermediate host is an organism within which a parasite does not sexually reproduce. ... The name snail applies to most members of the molluscan class Gastropoda that have coiled shells. ... 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. ... Asexual reproduction in liverworts: a caducuous phylloid germinating Asexual reproduction (also known as agamogenesis) is a form of reproduction which does not involve meiosis, gamete formation, or fertilization. ... The miracidium is the small free-swimming larva of some Trematoda including the Schistosoma. ... Metacercariae are minute cases, usually round or spherical, which house intermediate stages of parasites. ... Metacercariae are minute cases, usually round or spherical, which house intermediate stages of parasites. ... Metacercariae are minute cases, usually round or spherical, which house intermediate stages of parasites. ... The liver is the largest internal organ of the human body. ... This article discusses the medical condition. ... X-Ray of the bile duct during a laprascopic cholecystectomy A bile duct is any of a number of long tube-like structures that carry bile. ... An average Whooping Crane egg is 102 mm long, and weighs 208 grams In some animals, an egg (Latin ovum) is the zygote, resulting from fertilization of the ovum. ... Look up Fluke in Wiktionary, the free dictionary. ... Species See text. ...

Disease Biology

In the United Kingdom, Fasciola hepatica is an frequent cause of disease in ruminants - this is most common between March and December. Cattle and sheep are infected when they consume the infectious stage of the parasite from low-lying, marshy pasture. The effects of liver fluke are referred to as fascioliasis, and include anaemia, weight loss and sub-mandibular oedema. Diarrhoea is only an occasional consequence of liver fluke. Liver fluke is diagnosed by yellow-white eggs in the faeces. They are distinguishable from the eggs of Fascioloides magna, although the eggs of F. magna are rarely passed in sheep, goats or cattle. A ruminant is any hooved animal that digests its food in two steps, first by eating the raw material and regurgitating a semi-digested form known as cud, then eating the cud. ... Pastureland Pasture is land with lush herbaceous vegetation cover used for grazing of ungulates as part of a farm or ranch. ... This article discusses the medical condition. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Edema (BE: oedema, formerly known as dropsy) is swelling of any organ or tissue due to accumulation of excess fluid. ... Diarrhoea is the correct way to spell the word Diarrhoea. ... Rabbit feces are usually 0. ... Fascioloides magna (Large American liver fluke, Giant liver fluke) Fascioloides magna is up to 100 mm long, thick, and oval; it is distinguished from Fasciola spp by the lack of an anterior projecting cone. ...

A serious consequence of the liver damage caused by fascioliasis is that latent Clostridium novyi spores can be activated by the low oxygen conditions in the damaged tracts the parasite forms in the liver - this can lead to "black disease", caused by Clostridium novyi type B or immune-mediated haemolytic anaemia (IMHA) leading to haemoglobinuria caused by Clostridium novyi type D. The liver is the largest internal organ of the human body. ... Species Clostridium acetobutylicum Clostridium aerotolerans Clostridium botulinum Clostridium colicanis Clostridium difficile Clostridium formicaceticum Clostridium novyi Clostridium perfringens Clostridium sordelli Clostridium tetani Clostridium piliforme Clostridium tyrobutyricum etc. ... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless (gas) very pale blue (liquid) Atomic mass 15. ... In medicine, haemoglobinuria is a condition in which the oxygen transport protein haemoglobin is found in abnormally high concentrations in the urine. ...

Treatment

The drug of choice in the treatment of fasciolosis is triclabendazole, a member of the benzimidazole family of anthelmintics. The drug works by preventing the polymerisation of the molecule tubulin into the cytoskeletal structures, microtubules. Unfortunately, resistance to this drug is rising worldwide. Some populations of liver fluke, for example in Australia, the Netherlands, southern Ireland and the UK have shown to be persistant after treatment with this drug, which is administered orally at a dose rate of 10mg per kg weight of the animal. Albendazole and praziquantel have been used. Triclabendazole (commercial name Fasinex) is a member of the Benzimidazole family of anthelmintics. ... Benzimidazole is a heterocyclic aromatic organic compound. ... Anthelmintics (in the U.S., antihelminthics) are drugs that expel parasitic worms (helminthes) from the body or kill them. ...