Why do my spayed female dogs suddenly fight when I'm not home?

Hi and thank you for using Petco Pet Education Center, formerly Petcoach! I am so sorry that your two pups have not been getting along recently. I would separate both dogs while you are away until you can figure out the issue. A lot of times housemates will fight due to phobias (thunderstorms, loud noises), separation anxiety or aggression. Also, sometimes one dog may have a medical issue presenting it self to be weaker than the other dog. I would make sure both pets are pain free and have no concerning issues like vomiting, diarrhea, weakness, pain etc.

A lot of the time, the newer dog in the household tends to be the aggressor. I would work with each dog separately and together for obedience training. If possible, i would get a professional dog trainer to help. A lot of the time it is the people that need training on how to properly time commands for their pups.

Once they have a solid foundation of obedience training I would try a few things that will test ability to ignore one another in the same room, then give one dog attention while the other one ignores it etc. I would reward the dogs for remaining calm. This will help teach them that they can be in the same space and tolerate each other.

These can be some helpful training tools that you can start with. However, if the fighting escalates, getting a professional trainer would be highly recommended sooner rather than later!

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