When my then one year old 90 lb lab approached one year old I had to give in and purchase a prong collar. He absolutely went nuts to scape off the halti as did your pup and the body harness only worked to a small degree. The prong has been a great tool for us. Many people look at them (myself included prior to this) and think they look like a torture device but in fact they are much more humane then a regular choke collar. I would definately advise that you find a trainer that can show you how to fit and use the collar correctly. Also be sure to look for a quality collar (Herm Sprenger) is the best design and not one of the cheap knockoffs as they can have poorly finished prongs. I also personally like the quick release model for ease of putting on. Here are a couple great articles to consider.
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