Ranikhet disease is caused by

Options

A. bacteri
B. virus
C. fungus
D. parasite

Answer

**Step-by-Step Solution:**

1. **Identify the Disease**: The question asks about Ranikhet disease, which is known to affect poultry, particularly chickens.

2. **Determine the Causative Agent**: Ranikhet disease is caused by a specific type of virus. In this case, it is caused by the paramyxovirus.

3. **Understand the Symptoms**: While the question specifically asks for the causative agent, it is helpful to note the symptoms associated with Ranikhet disease for a comprehensive understanding. Symptoms include:
- Sneezing
- Nasal discharge
- Coughing
- Diarrhea (which can be greenish or white)
- Depression in birds
- Anorexia (loss of appetite)
- Muscular tremors

4. **Mode of Transmission**: The disease spreads through respiratory secretions such as sneezing, nasal discharge, and coughing from infected birds to healthy birds.

5. **Conclusion**: Therefore, the answer to the question "Ranikhet disease is caused by" is the paramyxovirus.

**Final Answer**: Ranikhet disease is caused by the paramyxovirus.

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