Runaway collie

Please help! I have five lovely Border Collie rescue bitches; the last two are a rescued breeding bitch and one of her last litter. The problem is when we are on walks the mum runs off with any small dog we pass and pesters the life out of it, as well as its owner. She won’t heed my recall at all.

I have had mobile calls from irate people as far as a mile away when I have considered it a safe distance to let her off lead with the others (one of which is her own puppy), but she will remember the last small dog we have passed and slips away.

I don’t want her to spend her last years on a lead, after the sad life she has led, and I don’t really want to spay as she recently had a very bad reaction to anesthetic when having some teeth out. I’m also not sure that it will make any difference.

This is really getting me down and it is spoiling the walks for all the other dogs. Obviously I can’t be cross when I do eventually recapture her, but it seems to me that she does not want to be with us at all, although she is very loving and waggy at home.

Any ideas?
Chris, by email