Discussions on dealing with aggressive dogs usually turns in the direction of how to deal with these situations when they occur but should be directed to prevention. People speak of correction and control in training when they should speak of refocusing and promoting correct behavior. As a long term Flyball team member, captain of a consistent top ten team, owner of several successful Flyball dogs, and mostly as a professional trainer who has a large amount of experience in solving aggression cases; I am going to put my two cents in.
First of all, let's clarify prey-drive versus chase drive. A prey driven dog will chase with a great deal of focus on the object it is pursuing and a definite goal of attaining access to its target. A chase driven dog will also chase but usually not with the same intensity or absolute drive to reach its target as the end goal. Many of you have done chase games with both types of dogs. The prey driven dog will drive as hard as it can until it reaches you and when it does you or your toy usually gets hit like a ton of bricks. The chase driven dog can be somewhat frustrating as it will chase you, but not with the drive or intense targeting behavior of the prey driven dog. This dog will often pursue the handler in chase games, but will run on by and not follow through to actually catch the handler. The chase driven dog usually does not exhibit the sudden increased burst of speed that a prey driven dog will when the handler increases their speed. Unfortunately, either tendency can lead to dog chasing and/or aggression (more so in the prey driven dog).
First of all, let's clarify prey-drive versus chase drive. A prey driven dog will chase with a great deal of focus on the object it is pursuing and a definite goal of attaining access to its target. A chase driven dog will also chase but usually not with the same intensity or absolute drive to reach its target as the end goal. Many of you have done chase games with both types of dogs. The prey driven dog will drive as hard as it can until it reaches you and when it does you or your toy usually gets hit like a ton of bricks. The chase driven dog can be somewhat frustrating as it will chase you, but not with the drive or intense targeting behavior of the prey driven dog. This dog will often pursue the handler in chase games, but will run on by and not follow through to actually catch the handler. The chase driven dog usually does not exhibit the sudden increased burst of speed that a prey driven dog will when the handler increases their speed. Unfortunately, either tendency can lead to dog chasing and/or aggression (more so in the prey driven dog).
Secondly, let's apply this to Flyball training. All are born with different levels of pre-dispositions towards movement fixation. The funny thing here is that the dogs with strong prey-drive can potentially be some of the best Flyball dogs. Dogs very much learn what to fixate on. Unfortunately, many dogs learn to fixate on other dogs very early in their training. Practices such as letting the dog watch, or tying them to walls during practices, or running with a pack too much early in their career can be a major culprit. It is a known fact that a restrained dog watching movement go by will usually begin to fixate on the moving object. Everyone in Flyball knows this or why else would we build speed and drive through "restraint" recalls. Eventually through frustration, the restrained observing dog may become aggressive towards the moving dog. When a dog does not know the game and is watching, the most interesting thing is the dogs running by. So, those leaping, barking restrained dogs are not keen to play the game, but are keen to chase the dogs. Therefore, we must make these tendencies work for us and not against us. Do not let green dogs spend their time learning to develop a moving dog fixation; and certainly do not let already problematic dogs feed their fixation. In order to do this you may loose ten pounds, but the bottom line is the handler needs to get physical. My basic rule with a new dog or an already problematic dog is he is always playing chase games with me when he is around moving dogs. If a pre-existing severe focus problem exists then we begin around one non-moving dog and gradually build up. The idea is to develop a mind-set in the dog that the movement going on around him is insignificant and never involves him, and that you are the only interesting target . This takes a great deal of effort on the owners part as it is physical, and hard work to run around focusing your dog on your movement only(Tug games are excellent for this). It is certainly much easier to establish in a new puppy with no pre-conceived ideas. It can be a bigger project when you are trying to solve a pre-existing problem, but it is do-able. I am not saying that you would not use correction at all, but it is much more reliable to have a dog with this altered owner driven mind set than to rely on a negative consequence to make the dog restrain himself. I am also concerned over comments that the dog prey drives to get the ball and brings it due to the control you have on him. What all the top teams know is that the retrieve of the ball is only an activity en route to the drive to pursue and catch the handler. If the chase or prey drive is harnessed toward the handler; the other movement around is of little interest to the dog. One last note on this issue; I do not use the rest of my pack to exercise a new puppy. I go out one-on-one and play all those fun doggy games with him. He will be with the pack or other dogs enough to be properly socialized, but the majority of play time is with me. As I stated at the beginning, dogs learn what is fun to focus on; make sure that it is you. By, the way; for those of you worrying about having enough time to treat a new dog as an individual, I recently raised #12 of a pack of 12.
A final word: There are many roads to the same destination, I have just outlined one of them. These ideas are meant for a dog who has chase or prey driven problems; not for dogs with generalized offensive or defensive dog aggression problems which would also present other factors to be dealt with. I hope this helps some of you, or at least gives you some food for thoug