Hello everyone, glad to see this forum. I own 2 basenji's a mother and daughter. Mother is tri and daughter is red. The mother is 2.5 years old and has been a lovely dog to raise. Recently she was attacked by an animal (I live in the mountains near national parks) and has become agressive to other dogs while walking at a park. Before she would meet each dog and person and it was all good social interaction. Any thoughts on how to help this behavior?
Thanks

@goofylori Full check up and bloodwork including full thyroid panel, first.

Sadly things like this can increase issues, and she also may be maturing. I've seen many dogs that began becoming dog aggressive as they hit maturity. Of course, her having a puppy could bring those hormones way up. Was there a reason you bred her? Are you going to spay? Was the puppy with her when she was attacked?

Once the blood work and thyroid are clear, basic behavior training, ignoring, having people with dogs pass by and toss a treat until she isn't stressed about them being near... iow, baby steps to retrain her responses.

Yes to the suggestions to get her checked and also spay her.
Aggression may not necessarily be vicious but rather reaction to the scary situation she encountered. It can be dealt with through consistent and regular training (with treats to start) - you might try the Fenzi Dog Academy online classes (they have a great class for retraining reactive dogs). But regardless you need to be more aware of her surroundings and not put her in a situation that may be scary to her or at least get her attention back on you (treats) when you can't avoid the situation.