i agree with the other replies. I just wanted to add also though, my dad has a BC and when he was a puppy he used to get transfixed on things and chase them (namely cars and push bikes!) to brake the behavior we used a bottle filled with lentils or something equally noisy and when he started to show the behaviour (im sure you will recognise the warning signs in your dog) wee shook the bottle to snap him out of it, walked him away calmly then said good boy and gave him a treat. it worked very quickly and when he was allowed off the lead eventually just the sound of the bottle shaking got his attention and had him running back.

<<<it took a long story to say shake a bottle to help stop the behavior lol!

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