Sheep pick up infection of liver fluke from

Options

A. Redia
B. Cercaria
C. Metacercaria
D. Capsule

Answer

**Step-by-Step Solution:**

1. **Understanding the Organism**: The liver fluke, scientifically known as *Fasciola hepatica*, is a parasitic flatworm that infects the liver and bile ducts of its hosts, primarily sheep and cattle.

2. **Identifying Hosts**: The life cycle of the liver fluke involves two hosts:
- **Primary Host**: Sheep (or cattle) where the adult fluke resides and lays eggs.
- **Secondary Host**: Snail, which is essential for the development of the fluke's larval stages.

3. **Life Cycle Overview**:
- The adult liver fluke in the sheep lays eggs, which are excreted in the feces.
- These eggs hatch into a free-swimming larval form called **miracidium**.
- The miracidium infects the snail, where it undergoes several developmental stages, including **sporocyst**, **rediae**, and **cercaria**.

4. **Key Developmental Stages**:
- **Rediae**: A stage that develops from the sporocyst within the snail.
- **Cercaria**: This is a larval stage that has a tail and is released from the snail into the environment.
- **Metacercaria**: This is the encysted form of the cercaria, which loses its tail and is found on vegetation.

5. **Infection of Sheep**: The sheep pick up the infection by ingesting the **metacercaria** stage, which is encysted and typically found on aquatic plants.

6. **Conclusion**: Therefore, the correct answer to the question "Sheep pick up infection of liver fluke from" is **metacercaria**.

**Final Answer**: Sheep pick up infection of liver fluke from **metacercaria**.

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