Can my neutered male dog impregnate my unspayed female puppy?

If he was neutered a long time ago this is probably a dominant behavior not related to the sex hormones. If he was castrated recently he could have made her pregnant as the sperm may survive in various storage areas of the male reproduction tract for up to 6 weeks after neutering. Please post again on the forum if you would like to discuss it further. I hope my answer was helpful.

A neutered dog can still have sex – if he wants. If it has been long enough after the neuter, (typically they are completely sterile six to eight weeks after being neutered )he cannot impregnate the female.

Yes, I recommend to have her spayed between 5-6 months of age. It's hard to know exactly why he suddenly started doing that, It's possible she is coming into heat. It's also possible the mounting was not sexual in nature: https://www.petcoach.co/article/mounting-behavior/ I hope this helps.

Neutering doesn't remove all sexual behaviors, and male dogs who are neutered can still try to mate with females in heat. The good news is there is no way your female can get pregnant. The best way to stop that behavior from Jeeps is to have your female spayed. I hope this helps!

As long as the Rottie is spayed, she cannot get pregnant. However, mounting behavior is not always sexual and it can be seen in any dog. Here is a link: https://www.petcoach.co/article/mounting-behavior/ Monitor them closely to make sure the puppy is not overwhelming the Rottie but hopefully they will get along well. Best of luck.

Since they are both neutered, this behavior is likely caused by over-stimulation. It's not sexual, it's just an inappropriate outlet for being overwhelmed or overexcited -- think really tired toddler starting to throw things and hit his friends. I would recommend redirecting him to a toy or playing with you, or remove him calmly from the situation. You don't want to punish him for the behavior, but you do want to stop it.

Neutered males can display erections and ejaculate just like intact males. They may mount in a display of dominance or can still mount to breed in the presence of an intact and receptive female. Correct the behavior immediately (even though no litters will come of it) and distract or separate him completely from the female until she is no longer in heat. Consider having your female spayed in the near future.