We took our hound mix to the park for the last 6 months but in the last 6 months, there's been a change in her behavior. What could be causing this to happen?

Hello,

I'm hoping you can answer a question for me. We have been taking our very sweet and gentle hound mix to the dog park for the last six months. However, in the last month there has been a change in her behavior. She is becoming more and more aggressive toward other dogs, in particular smaller dogs. Also, she is becoming more and more disobedient.

We have cut the dog park out of her life now. I'm wondering what could be causing this to happen though?

Thank you for any information you might have.

Paul