Good question! Actually it is pure bred dogs who are more prone to diseases. This is because they are more likely to inherit certain genetic mutations from their parents. This is because there parents are more closely related!
answered on 16 Nov 2018:
last edited 16 Nov 2018 2:10 pm
The main idea is the bigger the mixture of your immune genes, the better your chances of survival. This is because you may get different types of immune genes from different parents who are not related to each other, so then the baby is more likely to fight off invaders better. 🙂