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Why is my spayed puppy acting like she's in heat? Is she truly spayed?

Updated On September 23rd, 2025

Pet's info: Dog | English Mastiff | Female | spayed | 5 months and 9 days old | 40 lbs

Puppy was spayed at 16 weeks and last two days is acting like a dog in heat there is no blood but she is backing up to our male dog who is fixed and must be giving him a smell he keeps trying to mount her which he has never tried to before how would I know that she is truly spayed and did the vet that fixed her accident miss something does that ever happen and how would I know

1 Answer

Most Helpful Answer

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Answered By Dr. Elizabeth

Veterinarian

Published on July 21st, 2019

This does sound suspicious for a heat cycle BUT dogs can also mount and present the rump to entice play or exhibit dominance or general (non-sexual) excitement. I do recommend to have Athena examined and have some hormone levels checked. This is the best way to know if an ovary was left behind during her spay. Try to video record the behavior you are seeing as this can help the doctor as well. I hope this helps and best of luck.

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