Q. Why does your dog chase and jump on cars?
A. Most dogs have some instinct to chase moving objects. How strong the instinct is depends on the breed of dog. For example, dogs who were bred to herd or to assist humans in hunting usually have very strong instincts to chase, which may be aroused by anything from joggers to trains! Dogs will not automatically outgrow this behaviour. There are two ways you can handle it. Firstly, never give your puppy the opportunity to chase or lunge at cars – walk in areas away from traffic or at a distance where your puppy does not pay attention to it. Sometimes doing this until the pup is matured will help him forget about chasing cars and by the time he walks close to traffic again he will not find it as exciting.
Secondly, attempt to desensitise your puppy to cars and teach an alternative behaviour around them. This would involve starting your puppy off at a distance from a road or car park at which he does not pay much attention to traffic and teaching him to sit and watch you (using treats and a clicker) while cars go by. Once he has the idea and eagerly sits and watches you when you give him the cue to do so, start moving a little closer to the traffic so that it is more of a distraction and repeat the exercise. If at any stage he gets too distracted and can’t concentrate, back off a little and start working your way forward again. Over time, you would gradually close the distance while repeating the exercise so that he eventually learns to pay attention to you regardless of how close the cars are. (Start off with slow-moving cars – like in a car park – before moving on to faster and more exciting cars.)
For most dogs who love to chase moving targets, it is an excellent idea to get them hooked on a ball or other toy so that they can have an acceptable outlet for the behaviour. Once dogs have a favourite thing to chase, they will often focus on that and leave other moving targets alone!
-Taryn Blyth, dog behaviourist and trainer
Q. Are you over-exercising your puppy?
A. It is believed that episodes of recurring trauma to joints can contribute to the development of joint diseases such as elbow dysplasia and hip dysplasia. It would seem prudent to avoid excessive exercise during development of the skeleton of young, large breed dogs. I especially like to avoid or minimise exercise that may 
result in high impact concussive forces being placed on the joints. Avoiding flights of stairs or running on artificial surfaces such as tarmac would therefore seem sensible. Other important factors in the development of joint diseases are nutrition and genetics. It is important that these puppies are fed a good quality, correctly balanced diet in the correct quantity, as over nutrition has been shown to increase the risk of joint disease. Also, careful selection of animals in breeding programmes is vital for the long term prevention of these often severely debilitating illnesses.
