Maximum number of existing transgenic animals is of:

Options

A. Pig
B. Fish
C. Mice
D. Cow

Answer

**Step-by-Step Solution:**

1. **Understanding Transgenic Animals:**
- Transgenic animals are those whose genetic material has been altered using genetic engineering techniques. This manipulation is often done for research purposes, such as studying gene function, disease mechanisms, and drug effects.

2. **Identifying the Options:**
- The question provides four options regarding which type of transgenic animal has the maximum number of existing specimens:
1. Pig
2. Fish
3. Mice
4. Cow

3. **Analyzing Each Option:**
- **Pigs:** While pigs can be genetically modified, they are not the most common transgenic animals used in research.
- **Fish:** Transgenic fish are used in research, but they do not outnumber transgenic mice.
- **Mice:** Mice are the most widely used transgenic animals, accounting for approximately 95% of all existing transgenic animals. Their genetic similarity to humans makes them ideal for studying human diseases and testing drugs.
- **Cows:** Some transgenic cows exist, but their numbers are significantly lower compared to mice.

4. **Conclusion:**
- Based on the analysis, the maximum number of existing transgenic animals is found in mice. Therefore, the correct answer is option 3: Mice.

**Final Answer:**
The maximum number of existing transgenic animals is of **Mice** (Option 3).

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