White leghorn fowl is a Mediterranean/American breed.

Answer

**Step-by-Step Solution:**

1. **Identify the Breed**: The White Leghorn fowl is a specific breed of poultry known for its high egg production capabilities.

2. **Origin of the Breed**: The White Leghorn is classified as a Mediterranean breed, which means it originates from the Mediterranean region.

3. **Egg Production**: This breed is particularly valued for its prolific egg-laying ability, producing between 200 to 280 eggs per year.

4. **Introduction to India**: The White Leghorn was introduced to India from its native region to enhance egg production in the country.

5. **Extinction of Local Breeds**: Due to the high productivity of the White Leghorn, local poultry populations may have declined or become extinct as they were replaced by this exotic breed.

6. **Clarification on American Breed**: The White Leghorn is not considered an American breed; it is strictly categorized under Mediterranean breeds.

**Final Conclusion**: The White Leghorn fowl is a Mediterranean breed known for its high egg production, and it is not classified as an American breed.

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