Boxers can be good at agility but it all depends on the individual dog of course. I would recommend getting puppy and reg obedience out of the way first. Also no jump training while your pup's hips and developing, it is also a good idea to get his hips and everything checked out and cleared by your vet before you even start agility training.
As for the A-Frames, etc. those you can start getting him used to at an earlier age.
As for the A-Frames, etc. those you can start getting him used to at an earlier age.
