Name the disease of silkworm caused by protozoan parasite. Mention the preventive measures against this disease.

Explanation

**Step-by-Step Solution:**

1. **Identify the Disease:**
The disease of silkworm caused by a protozoan parasite is known as **Pebrine disease**.

2. **Causative Organism:**
The specific protozoan responsible for Pebrine disease is **Nosema bombycis**.

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