No, they still come into heat every 6 months, just you account that 2 months is down from the last cycle, pups are born, and you have roughly another 3-4 months before she should cycle again. Some dogs cycle more often though so it depends on the bitch - but no, she should not be able to get pregnant directly after having a litter.
My concern is that we recently rescued a female dog and one of her puppies. The pup is now about 12 weeks old. The mom was spayed today and the vet found that she was pregnant again.
My concern is that we recently rescued a female dog and one of her puppies. The pup is now about 12 weeks old. The mom was spayed today and the vet found that she was pregnant again.