Inbreeding depression can be overcome by

Options

A. mating of animals of same breed , but having no common ancestors on either side of their pedigree upto 4-6 generations
B. mating males of one breed with superior females of another breed
C. interspecific hybridization
D. all of these

Answer

### Step-by-Step Solution:

1. **Understanding Inbreeding**: Inbreeding is the mating of closely related individuals within the same species. This process is often done over several generations (4 to 6 generations) to produce pure lines of animals, which increases homozygosity.

2. **Advantages of Inbreeding**: The main advantage of inbreeding is that it can help in the expression of superior traits that may be present in the parent organisms. Through selective breeding, these desirable traits can be passed on to the offspring.

3. **Inbreeding Depression**: However, continuous inbreeding can lead to inbreeding depression, which is characterized by a decrease in fertility and productivity. This occurs because the genetic diversity is reduced, leading to the expression of deleterious alleles.

4. **Overcoming Inbreeding Depression**: To overcome inbreeding depression, it is essential to introduce genetic diversity. This can be achieved through a process called out-crossing.

5. **Out-Crossing**: Out-crossing involves mating individuals of the same species but with no common ancestors for at least 4 to 6 generations. This means that the animals being crossed should be unrelated to each other, which helps in restoring genetic diversity and improving fertility and productivity.

6. **Conclusion**: Therefore, the correct method to overcome inbreeding depression is through out-crossing individuals of the same breed that do not share common ancestors.

### Final Answer:
Inbreeding depression can be overcome by out-crossing individuals of the same species but unrelated for several generations.

---