Do liver flukes lay eggs?
Adult fluke lay eggs that are passed out onto pasture in the faeces. At suitable temperatures, a miracidium develops within the egg, hatches and migrates in thin films of moisture, actively seeking the snail host.
How does Fasciola hepatica reproduce?
Liver flukes reproduce both sexually and asexually. Adults are hermaphroditic, capable of both cross- and self-fertilization. The larvae stage known as sporocyst reproduces asexually with its offspring developing into rediae, which also multiply asexually. Adults live in the bile ducts of their mammalian host.
Where do the eggs of liver flukes hatch?
Liver Flukes The eggs pass into the lumen of the small intestine and leave the body in the feces. If deposited in fresh water, the eggs hatch into ciliated miracidia, which, upon penetration of the correct species of snail, undergo several developmental stages and produce large numbers of cercariae.
When the liver fluke egg hatches What organism does it infect first?
The first host is a snail, while the second intermediate host is a lizard, toad, gecko, or skink. Cats become infected with this fluke after ingesting an infected second intermediate host. The prepatent period for the fluke is 8 weeks.
What is the infective stage of Fasciola?
Metacercariae are quiescent infective stages which can survive on aquatic vegetation or in water for several weeks. Mammals become infected when they ingest metacercariae with food or water (many human infections have been linked to the consumption of watercress).
How many eggs do liver flukes lay?
After 3–4 months, the juvenile flukes reach the deep-seated bile ducts where they mature sexually and initiate egg production. The adults lay, on average, between 8000 and 25 000 eggs per day.
What are the characteristics of Fasciola hepatica?
The Adult Worm – Averaging 30mm in length and 13 mm in width, Fasciola hepatica is one of the largest flukes in the world. The adult worm has a very characteristic leaf shape with the anterior end being broader than the posterior end and an anterior cone-shaped projection.
Is Fasciola hepatica a hermaphrodite?
Life Cycle. Fasciola hepatica is a hermaphrodite and auto-fertilization is achievable, although cross-fertilization between two adult flukes is the most common form of sexual reproduction.
What do the eggs of Fasciola hepatica look like?
Eggs of F. hepatica are operculated with characteristic yellowish brown colour ( Andrews, 1999 ). They are not readily differentiated from eggs of F. gigantica ( Chen et al ., 1990 ). The miracidium of F. hepatica (130×28 μm) comes out of the egg and swims at great speed.
How are eggs and miracidium of Fasciola studied?
Light Microscopy (LM) and Scanning Electron Microscopy (SEM) were used to study the egg and miracidium of Fasciola gigantica and redia, cercaria and metacercaria from field infected Lymnaea (cailliaudi) natalensis snails, to analyze the differences between eggs and intra-molluscan stages of F. hepatica and F. gigantica in a zone of sympatry.
Which is an intermediate host for Fasciola hepatica?
At least 20 snail species have been identified as intermediate hosts for one or more Fasciola spp. Snail species may differ with respect to their suitability to serve as intermediate hosts for F. hepatica versus F. gigantica; host ranges for both Fasciola spp. are a subject of ongoing research.
Where is Fasciola hepatica found in the world?
Fasciola hepatica is found on all inhabited continents, in more than 70 countries, particularly where sheep or cattle are raised. Human infections have been reported in parts of Europe, the Middle East, Latin America (e.g., Bolivia and Peru), the Caribbean, Asia, Africa, and rarely in Australia.