i would say as she only does it when shes around other dogs or hears others dogs shes doing it cos she gets worked up and mistakes the other dog for being aggresive. my scampi use to do it, he would bark at another dog and then cos he was worked up he would attack one of my others by mistake. when she gets aggressive dont make a fuss as she will think your worried and maybe even thinks that your worried about the other dog and so attacks it to protect you, when she goes for the other dog tell her no and put her in another room for a few moments or dont take any notice of her for a while untill she has carmed down.
