I am now understanding why my foster dog needs to wear the muzzle when out. He is reactive to other dogs. I took him up to a local playing field tonight to do a bit of training. He was doing very well looking at dogs at a distance and staying under threshold. Because I was using treats to reward him once again I had taken the muzzle off. He is no good at taking treats when wearing the muzzle. I also use a ball as a reward as he is very ball motivated. He was on a 3 ft lead which was securely round my wrist and I was staying at a distance from the other dogs.

Unfortunately a little old lady was out with a small terrier. It had been playing with other dogs and we had been watching it from a distance of 100-150yd. After a while I turned away to carry on with our walk. Unfortunately the old ladies dog decided to follow us. Foster was pulling backwatds towards the dog and I was walking away dragging him to try to put some distance between us and the dog but the dog speeded up. I called over to the lady who was busy chatting to people and seemed totally oblivious to the fact that her dog was following us across the field. She probably couldnt hear because of the distance. However she did eventually notice something was amiss when her dog reached us and started barking madly at us. Foster of course was barking madly back and trying to get to the dog and I was desperately trying to drag him away.

The woman did eventually arrive and tried to catch her dog which just kept out of her reach. Foster by this time had totally lost it and was barking and leaping about. I must admit I was very tempted to let him go towards the dog and maybe being possibly bitten would have made the dog back off. but decided that wasnt an option. Anyway foster by this time was barking and also biting, Thankfully he only connected with me but I now have a bite on my wrist and on my stomach. Bruised and skin broken :(

Obviously it is my fault for getting into this situation. I dont think my training skills are up to dealing with a dog like this. My question is can a dog that redirects  when over threshold like this be desensitised to a point where he wont lash out and bite what ever comes within reach. He could easily have bitten the woman who having got hold of her dog was trying to talk to me and wouldnt go away. The dog was still barking like mad and trying to get to mine still. I dont think she had any idea of how close she was to getting bitten.

I will suggest the rescue place refer him to a behaviourist and I will return him to them. I just feel so bad that my attempt at training have gone so badly wrong. How do people use treats with muzzled dogs. I have  found a wire coated greyhound muzzle which seems to fit well but he cant seem to get the hang of taking treats when wearing it. I tried  the new baskerville muzzles but couldnt  find one that fitted his slim head.

yes dogs like you describe can be changed but it takes time and patience.

Good treats for use with a muzzle are things like this http://www.ardengrange.com/pet-food/dog-treats-liver.asp or squeezy cheese

Yikes it was only 3 days ago you were worried about being prosecuted under the DDA, I wouldn't have thought you would have had the dog out without his muzzle on again!

Anyway, that aside, with sighthounds and lurchers long noses it is actually quite easy to shove a treat through the muzzle into the side of their mouth (not the front), a few will drop initially but both you and the dog will get better at it.

Please, please, please don't take this dog out without a muzzle on again. Playing with the ball will have to be restricted to the garden.

Redirected aggression like this is quite common and yes it can be 'cured' slowly, slowly is the answer.

You can get balls with sticky-out bits that can be grasped through a muzzle, I can't think what they're called but they resemble an underwater mine!

Dogs like this certainly can be changed but it does take time, a lot of patience and not a little bit of practice to get into the swing of it!  Other people will always set it back such as this woman with the terrier - but this is why it's so important to keep that muzzle on.  You can set your foster up to succeed as best as you can but you cannot control other people.  What you can do is try to distract other dogs that come over - throwing a handful of treats on the ground in front of them can work quite well as they stop to sniff them out, giving you a chance to leg it.  I've heard quite a few people say that shouting 'sit!' in the voice of doom can often be effective too although I've never tried it.

In future I would keep everything to a minimum to begin with.  So if you see dogs playing like this one again, do a tiny bit of work far away (rewarding for looking at the dogs and for looking away/turning away) then leave before anything can go wrong.  Less is more with reactive dogs.

Also, if you do have a day like yesterday (and you will), do make sure you give him a few days' break at least to let the stress levels drop back down again.  Stress stacks and sticks - each time he sees another dog a little bit of stress will stack up, a big bit if it's a full kick-off like yesterday, and each bit of stress sticks around for a few days or more (depending on the dog and the level of the stress - e.g. Phoebe is terrified of hoovers but gets over it within minutes these days, but a ride in the car would take her at least a week to recover from).  It's very easy to end up with a dog permanently wired from stress if you don't give them sufficient rest inbetween exposures, and in that state you won't make any progress and reactions are much more likely.