Name the most efficient converter of low fibre food stuff into highly nutritious animal protein food.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the most efficient converter of low fiber food into highly nutritious animal protein food. This indicates we are looking for an animal that can take in low fiber food and convert it into protein-rich food.

2. **Identifying the Animal**: Among various animals, poultry birds are known for their ability to convert low fiber food into high-quality protein. Poultry birds include chickens, ducks, and turkeys.

3. **Nutritional Value of Poultry**: Poultry birds are recognized for their high protein content, which can be around 21%. They also contain essential fats (approximately 4.5%), vitamins, and minerals such as zinc, iron, and magnesium.

4. **Conclusion**: Based on the above points, the most efficient converter of low fiber foodstuff into highly nutritious animal protein food is poultry birds.

**Final Answer**: Poultry birds.

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