Here's how it works:
* Ovulation and Fertilization: Female dogs can ovulate multiple eggs during their heat cycle.
* Multiple Matings: If the female dog mates with more than one male during her fertile period, each male can fertilize a different egg.
* Litter with Mixed Paternity: This results in a litter of puppies with different fathers, each carrying the genes of the male that fertilized the specific egg they developed from.
Important Note: Superfecundation is not always easy to determine without genetic testing. The puppies might look similar, but their genetics can be quite different.