Can a 50lb male dog breed with 28lb female safely?

Yes, a 50 lb male dog can safely breed with a 28 lb female dog, as long as both dogs are healthy and of appropriate breeding age. Generally, the size difference is not significant enough to pose a risk during mating or pregnancy. However, it's essential to ensure that the female is not too small for the male to avoid complications during the delivery process. Consulting with a veterinarian before breeding is always recommended to assess any potential risks.