It requires two hosts: the herbivorous animals (such as cows, sheep, goats, birds, among others) or omnivores, including humans, serve as definitive hosts, while molluscs lungfish fresh water of the genus Lymnaea act as intermediaries hosts.

The life cycle of a trematode includes several stages in their way adult:

• egg.
• miracidium.
• sporocyst.
• redia.
• cercaría.
• metacercaria.

In some species, may you be missing any of the larval stages, or there may be multiple generations of a larval stage specific.

Eggs they are produced in large quantity and have a variable morphology, although generally oval in shape. Depending on the species, the eggs may be released into the external medium, with or without embryo. With the notable exception of some cases, the eggs must come down to the water, where, under specific conditions of oxygen, temperature and light, develops the first larval stage, known as miracidia.

The miracidia it is a larva, small and ovoid, elongated, and covered by layers hair flat. At its anterior end, there is a papilla apical that can be extended, with two types of glands: the gland apical, which is located in the center, and the glands penetrationlocated on both sides of the previous one; the secretions of these glands help to break down the tissues of the host during the process of penetration of the miracidia.

To find your first host, typically a mollusc such as a freshwater snail, the miracidia penetrate its interior and is transformed into esporoquiste; this presents a wrap simple and contains germ cells that give rise to the next generation larval, the redias.

The redia it has a digestive system simple and germ cells that will generate the following larval form known as cercaria, que emerge a través de la pared de la redia o por un orificio específico. La cercaria presenta una notable diversidad morfológica según los diferentes grupos; al estar en el agua, nada en búsqueda de un segundo hospedador intermediario o una planta, donde se enquista como metacercaria.

The metacercaria must be ingested by the definitive host; in the intestine, thanks to the action of the enzyme, is released from its envelope and migrates to its final location, where it is converted to the adult state. In the esquistosomátidos, the cercaria is actively looking for the definitive host and enter in it.

Under optimal conditions of temperature, ranging between 9 °C and 26 °C, the cercariae emerge from the snail and must enquistarse to continue their development as adults in a host compatible. To do this, when in contact with a plant or other submerged object, they lose the tail and enquistan (metacercarias). In this phase can survive for prolonged periods of up to 10 months or more, if the environmental conditions are favorable.

Some small mammals, birds, amphibians, fish, or certain insect larvae feed on freshwater snails. In favourable conditions, predators and snail populations can increase rapidly, maintaining a balance, although they can also experience a significant shift. This is seen, for example, in the intensive rearing of ducks and geese in Germany, which is performed to control the F. liver (LEVINE, 1970).

The preferred treatment for all infections by tapeworms is praziquantel, an antiparasitic and broad spectrum that contains a 10 % praziquantel for the treatment and control of intestinal parasitoses in domestic poultry caused by tapeworms. The same applies to the rare trematodiasis intestinal.