Practice of mating of animals within the same breed, but having no common ancestors on either side of their pedigree upto 4-6 generation is

Options

A. inbreeding
B. out crossing
C. cross breeding
D. line breeding

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the practice of mating animals within the same breed, ensuring that there are no common ancestors in their pedigree for up to 4-6 generations.

2. **Identifying Key Terms**: The key terms here are "same breed," "no common ancestors," and "4-6 generations." This indicates that we are looking for a specific type of breeding practice that maintains genetic diversity within a breed.

3. **Evaluating Options**:
- **Inbreeding**: This involves mating closely related individuals within the same breed, which means they share common ancestors. Therefore, inbreeding does not fit the criteria of having no common ancestors for 4-6 generations.
- **Outcrossing (Outbreeding)**: This practice involves mating animals of the same breed that do not have common ancestors for several generations (4-6 generations). This aligns perfectly with the question's requirements.
- **Crossbreeding**: This refers to mating individuals from different breeds, which is not applicable in this scenario since we are focusing on the same breed.

4. **Conclusion**: Based on the evaluation of the options, the correct answer is **outcrossing**. This practice allows for the introduction of genetic diversity while maintaining the breed characteristics.

**Final Answer**: The practice of mating of animals within the same breed, but having no common ancestors on either side of their pedigree up to 4-6 generations is called **outcrossing**.

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