Pebrine disease in silkworm is caused by

Options

A. Nosema
B. Eimeria
C. Opalina
D. Vorticella

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the causative agent of Pebrine disease in silkworms. We need to identify which of the given options is responsible for this disease.

2. **Analyzing the Options**: The options provided are:
- A) Nosema
- B) Emeria
- C) Opalina
- D) Vorticella

3. **Identifying the Correct Option**:
- **Nosema**: This is a protozoan parasite known to cause Pebrine disease in silkworms. It infects the silkworm and leads to significant health issues.
- **Emeria**: This organism is known to cause coccidiosis, a disease in poultry, not in silkworms.
- **Opalina**: This parasite is found in the intestines of frogs and toads and does not affect silkworms.
- **Vorticella**: This organism is a proposed biocontrol agent for mosquito larvae and does not cause Pebrine disease.

4. **Conclusion**: Based on the analysis, the correct answer to the question is **Nosema** (Option A), as it is the only organism listed that is known to cause Pebrine disease in silkworms.

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