Which of the following diseases is/are poultry disease?
A. aspergillosis B. ranikhet disease C. gill rot D. black rot.

Options

A. Both A and B
B. Both C and D
C. Only C
D. Only D

Answer

To determine which of the diseases listed are poultry diseases, we can analyze each option one by one:

### Step 1: Analyze Aspergillosis
- **Definition**: Aspergillosis is a fungal disease caused by the fungus *Aspergillus fumigatus*.
- **Impact on Poultry**: This disease primarily affects chickens and leads to respiratory infections, which can result in stunted growth or retarded development.
- **Conclusion**: Aspergillosis is a poultry disease.

### Step 2: Analyze Ranikhet Disease
- **Definition**: Ranikhet disease, also known as Newcastle disease, is a viral infection.
- **Impact on Poultry**: It specifically targets chickens and is caused by the Newcastle disease virus (a type of paramyxovirus).
- **Conclusion**: Ranikhet disease is a poultry disease.

### Step 3: Analyze Gill Rot
- **Definition**: Gill rot is a disease that primarily affects fish.
- **Impact on Poultry**: Since it occurs in aquatic animals, it does not affect poultry.
- **Conclusion**: Gill rot is not a poultry disease.

### Step 4: Analyze Black Rot
- **Definition**: Black rot is an infection that affects grafts and is not related to poultry.
- **Impact on Poultry**: This disease does not impact birds or poultry in any way.
- **Conclusion**: Black rot is not a poultry disease.

### Final Conclusion
From the analysis:
- **Poultry Diseases**: Aspergillosis and Ranikhet disease.
- **Non-Poultry Diseases**: Gill rot and Black rot.

Thus, the correct answer is **A (Aspergillosis) and B (Ranikhet disease)**.

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