Question: What's the worst Paracite for Animals?

Marisol Collins answered on 13 Nov 2016:

Hallo! What a great question! There are some pretty nasty parasites out there, too many to mention! One that comes to mind is a type of flat worm called a liver fluke. It’s called Fasciola hepatica, and it feeds on blood. There are many different types of liver fluke, but there is one that can affect sheep and cattle, and it causes a lot of problems in many parts of the world. I’ll describe how the parasite lives – are you ready for a crazy story? Here goes..

The adult parasite looks a bit like a flat leaf, about 2-3 centimetres long. It has a really interesting lifecycle, that involves many different stages as it grows from egg to adult. This includes some time swimming around in water, then finding a special little water snail (it has to be this type of tiny snail, no other), working its way inside the snail, growing a bit inside the snail, coming out of the snail, and forming a tough little shell and waiting in water, or on plants in the water, to be drunk or eaten by a grazing sheep or cow. It then finds its way through the wall of the intestine of the animal, through the body to the liver, where it stays as an adult. As you can imagine, lots of these invading at once can make an animal very ill! That is some parasite though, eh?