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Why is my female dog suddenly acting male, marking, and humping?

Updated On September 23rd, 2025

MY female dog is starting to behave like a male dog? I got my dog 5 months ago she is 3 years old this behaviour only started within the last few days she is marking her scent everytime she sniffs something and when I let her off leash she doesn’t want to come back she too busy marking her territory everywhere and she’s also humping my other female dog I’ve had her 5 months and she’s never done This before only been happening since the beginning of the week xx

1 Answer

Most Helpful Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on April 16th, 2018

If your female dog isn't spayed, she could be coming into heat causing this behavior. Female dogs go into heat around every six months, and if you have had her for five months, it would be about time to go into heat again. This behavior will continue every six months unless you get her spayed, which I highly recommend getting done. Best of luck!

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