The black tongue disease in dogs is associated with the deficiency of

Options

A. Menadione
B. Niacin
C. Retinol
D. Calciferol

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the disease known as "black tongue" in dogs and what deficiency it is associated with.

2. **Identifying the Options**: The options provided are:
- A) Manadione
- B) Niacin
- C) Retinol
- D) Calciferol

3. **Researching Black Tongue Disease**: Black tongue disease in dogs is a condition that has been observed to be similar to a human condition called pellagra, which is caused by a deficiency of niacin (Vitamin B3).

4. **Analyzing the Options**:
- **Manadione**: This is a form of Vitamin K, not related to black tongue disease.
- **Niacin**: Known to be associated with black tongue disease in dogs and pellagra in humans.
- **Retinol**: This is Vitamin A, which does not relate to this condition.
- **Calciferol**: This is Vitamin D, also not related to black tongue disease.

5. **Conclusion**: Based on the analysis, the condition known as black tongue disease in dogs is associated with the deficiency of niacin.

### Final Answer:
The black tongue disease in dogs is associated with the deficiency of **Niacin**.

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