• The Lancet Liver Fluke (Dicrocoelium dendriticum)
• Phylogenetic placement- Platyhelminthes
• Habitat- The adult life of the Lancet Liver Fluke is lived in the bile duct of grazing mammals such as sheep or cows, but it grows to maturity inside of the Terrestrial Snail and ant as it attempts to find a suitable host.
II. Anatomy
III. Form & Function
The Lancet Liver fluke lives the majority of its life in the bile duct of grazing mammals, such as sheep or cows, where it feeds on liver tissue through an oral sucker on the anterior of its body. The fluke has no separate system to eliminate waste, so any waste is also expelled through this oral sucker. The life of the Lancet liver fluke begins when sexually mature flukes reproduce in the liver. The newly laid fluke eggs are expelled in the feces of the grazing mammal, where they wait until they are consumed with the feces by the Terrestrial Snail (Cochlicopa lubrica). Once inside the snail, they flukes hatch and grow to their juvenile stage. Upon reaching this stage, the flukes begin to drill through the wall of the gut towards the digestive tract. This action reaches the attention of the snail, who attempts to defend itself by encasing the flukes in cysts and expel them in its mucus. Once the flukes are expelled by the snail, they lie in wait of an ant, who extracts moisture from the mucus trail of the terrestrial snail. Once an ant consumes this moisture, and brings it back to the colony for other ants, the flukes drill out of the ant’s stomach and into the brain, where they begin to control the ant. The controlled ant acts normal during day to day function in the colony, but from dusk until dawn the ants sit at the tops of blades of grass instead of moving back to the colony with the other ants. This is all an effort to be eaten by a grazing mammal, who often feed at these hours. Once a grazing mammal eats the grass the ant was sitting upon, the flukes end up inside the mammal’s intestine. The flukes then move from the intestine to the bile duct of the liver, where they feed upon liver tissue and reproduce. The eggs laid by the flukes are expelled in the feces of the mammal, and the cycle begins once again.
IV. Impact on World/Humanity
• Cases of human infestation by the lancet liver fluke are very rare and can be treated with Praziquantel at 25 milligrams per kilogram three times a day for one day.
• The flukes can cause liver failure if enough flukes infest the bile duct of a mammal, such as a sheep or cow, often causing economic loss among farmers.
V. Journal Article Review
Link to article---> http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1701347/pdf/brmedj02303-0034.pdf
The Journal Article found was not on the Lancet Liver Fluke, but on the fascoiasis
Hepatica liver fluke. The flukes are similar in the symptoms and damage caused by infection, so such an article is still pertinent. The Article in question details the infection of many adults and children who ate wild watercress from a bed near infected sheep and cattle. Soon after the consumption of the parasites, those infected began to feel symptoms of malaise, intermittent fever, night sweats, weight loss, some pain in the right coastal margin, and severe coughing in some. The adult patients were treated with intramuscular injections of emetine hydrochloride, and the children with oral doses of Chloroquine. After three weeks, all patients were discharged.
Video:
http://www.youtube.com/watch?v=ZgAEeisfHW8
Bibliography:
• Dicrocoelium dendriticum - Wikipedia, the free encyclopedia. (n.d.). Wikipedia, the free encyclopedia. Retrieved October 13, 2010, from http://en.wikipedia.org/wiki/Dicrocoelium_dendriticuHardman,
• E. W., Jones, R. L., & Davies, A. H. (1970). Fascioliasis-A Large Outbreak. Fascioliasis-A Large Outbreak, 1, 4. Retrieved October 13, 2010, from the PubMed Central database.
• Merck Veterinary Manual. (n.d.). The Merck Veterinary Manual. Retrieved October 13, 2010, from http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/22705.htm
• Panini. (n.d.). A Fluke of Nature. Panini's Home Page. Retrieved October 13, 2010, from http://hilbertspaces.com/articles/fluke/fluke.html
• Parasitic Mind Control [Documentary]: National Geographic.
-Dylan Burchett
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