Culture of miracidia from liver fluke eggs. Back to The Fasciola home page
If you are from an academic establishment and require eggs of Fasciola hepatica for teaching or research they can be obtained from an abattoir if you are able to establish a relationship with the veterinarian in charge. A phone call to management will also be necessary for permission but permission is often allowed in exchange for a contribution in kind of tea or biscuits.
A whole gall bladder from an infected bovine or a sheep is all that is required (perhaps two or three).
More than one animal from different farms may be necessary as while livers may show pathology the animals may have been treated before being sent to slaughter and as a result the eggs may be unviable.
When you get the gall bladders back to an approved laboratory you will need to pass the bile contents of the gall bladder through a pre-sievesof 0.15mm but most importantly onto a sieve mesh of 0.53mm which retains the eggs. Copious washing with tap water will reveal the eggs, often in their thousands, which can then be washed out via a funnel into a beaker for sedimentation . Sedimentiaton (about 5 mins should be allowed for a few centimetres of water) can be repeatedal a few times to reduce bacterial or fungal contamination during storage / embryonation.
The eggs can then be stored at 5C for a maximum of 8 weeks.
Embryonation of cleaned eggs
A sample of sufficient eggs should be transferred into a flat bottomed flask or bottle with about 2cm of tap water. This is to allow sufficient surface area for oxygen. Finally stoppered with non absorbent cotton wool as a filter against bacterial invasion the flask or bottle is double wrapped in aluminium cooking foil to keep out light. The container is then incubated at either 17 days at 22C or 10 days at 27C.
Returned to the fridge embryonated eggs still in the dark can be stored until required again for several weeks (a maximum of 8).
To observe hatching of miracidia
Take a sample from the bottom of the flask or bottle and place under a microscope (either a few drops open under a dissecting microscope or in a cavity slide with a cover slip for viewing with a compound microscope).
The exposure to light stimulates the hatching of the miracidia and to see this at high magnification look for eggs with a much expanded viscous cushion which will be about to hatch under increased pressure.
© Dr. Clive Bennett 2013
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