I'm a vet tech, and frankly I see nothing wrong with this picture. Yes 17 dogs may seem like a lot of dogs, which it is, to someone whos only had 1, 2, or 3 themselves at any one time. I myself only have 1( a Presa Canario), but that is because I've recently moved in with my parents and out of respect to them I don't have more(they have two).
Point being, sumbirdy says they're getting a new fence and was willing to try new types of chains/wires/etc. to keep the chaser in. This is their desicion to have these animals and its their desicion to keep(most of) them outdoors. If they had 73 dogs I'd be concerned and bring up the hoarder issue. The fact is they have 17 WELL taken care of dogs. If I remember correctly human civilization(as far as planned communities) didn't occur until around 5000 bc, well...that gives dogs thousands of years experiance as outdoor packs. I see people who can't take care of 1 or 2 dogs everyday who keep them inside and they still get tick born disease or blood parasites, injured do to keeping a collar on them while in a kennel or crate, and other various(or natural) injuries.
More power to you birdy, if I was still in my house I'd have a handful of presas. I think you've done a good job by keeping these dogs on preventatives, which is more than a LOT of indoor dog owners can say.
My suggestions would be to either build a fence, as you said you would, and/or experiment with some heavy duty ropes/chains/or wire ropes.Please keep us posted on this guy.Also maybe some obediance training or NILIF so he understands YOU are in charge and all of his freedoms and rewards come from you.It may not discourage the drive to chase the cars, but it may give you better control to call him before he starts to bolt.
-Dave
heres a link to a good NILIF guide( Nothing In Life Is Free)
http://k9deb.com/nilif.htm
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