Trichinella spiralis in the muscle of pig : Trichinella spiralis in the muscle of pig
Not all flatworms are ugly parasites : Not all flatworms are ugly parasites http://ip30.eti.uva.nl/bis/limno.php?menuentry=soorten&id=284
Examples of trematodes : Examples of trematodes Gyrodactylus (monogenetic, ectoparasitic fluke on fishes and frogs),
Clonorchis sinensis (Chinese liver fluke of man),
Fasciolopsis buski (intestinal fluke of man),
Fasciola hepatica (liver fluke of sheep. It causes 'liver rot' disease to sheep).
Schistosoma haematobium (blood fluke of man,
Slide 4 :
Fasciola : Fasciola Ecology of fasciolosis, ponds and creeks in direct vicinity of pasture
Fasciola & Fasciolopsis : Fasciola & Fasciolopsis Important parasite of livestock, ocasionally infects humans
Symptoms similar to Clonorchis but Fasciola is much bigger
Fasciolopsis buski the human intestinal fluke has similar ecology
Usually asymptomatic if not heavy burden
Trematodes or flukes : Trematodes or flukes Posses two suckers which they use to attach within the host
Muscular pharynx permits the worm to pump food into the blind gut
Know your flukes : Know your flukes The tegument (“skin”) is highly active in nutrient uptake
Actin spines are found in many species and help the worms to anchor themselves
Trematode life cycles : Trematode life cycles
Slide 10 : Life cycle of endoparasites is complicated involving 2 or 3 hosts.
Produce an enormous number of offspring by combining sexual and asexual reproduction cycles
Many larval forms are seen in the life cycle
Life cycle of liver fluke : Life cycle of liver fluke
The miracidium : The miracidium Highly motile due to the cilia on its surface
Have simple eyes and several chemical and mechanical receptors which they use to find the intermediate snail host
Penetration glands secrete proteases and other lytic enzymes on contact with appropriate host
Life cycle of the human blood fluke, Schistosoma haematobium that causes urinary or visceral schistosomiasis. : Life cycle of the human blood fluke, Schistosoma haematobium that causes urinary or visceral schistosomiasis.
Swimmer’s Itch - Cercarial Dermatitis : Swimmer’s Itch - Cercarial Dermatitis The schistosome cercaria (originating in specific snail species) accidentally enters human skin.
Swimmer’s itch cases have been reported from nearly every state. (Most predominant in the north). In addition, swimmer's itch has been reported from more than 30 countries.
Disappears without treatment (after up to 7 days)
Dicrocoelium dendriticum the lancet fluke : Dicrocoelium dendriticum the lancet fluke One metacercaria becomes the ‘brain worm’ and lodges into the brain and manipulates the behavior of the ant.
In the evening when the temperature drops they experience spasms of their manidibles
Leucochloridium sp. : Leucochloridium sp. A tiny digenic trematode l
In the gut of small song birds
Worm eggs are passed with the feces and are taken up by amber snails.
Miracidia hatch, penetrate the gut epithelium and develop into sporocysts within the hepatopankreas.
Within the sporocyst cercaria develop which infect birds that eat infected snails.
Slide 17 : Amber snails, Leucochloridium sp.
(uninfected) Infected Snail Sporocyst dissected from a snail