I think approaching a qualified behaviourist would probably be best to help you with this, but I just wanted to add that wanting these two dogs to be best buds might be too ambitious - labs and collies have opposite playing styles. If you watch two labs playing, it's very physical, they're wrestling and body-checking and plowing into each other. Watch two collies play and you'll probably see them chasing, running and 'herding' each other with little to no physical contact. They're like a rugby player and a distance runner.

I expect that to the collie (who might already have been a bit sensitive about other dogs) what the young lab did was the equivalent of a 4-metre tall toddler grabbing you by the legs and excitely bouncing you up and down. Sure, it was meant well, but it was really unpleasant and possibly painful for a sensitive collie. No wonder he's saying BUZZ OFF! as loudly as he can now!

I think there are things you can try to defuse the situation a little (not letting the Lab harass the collie!) but certainly until the lab is a more polite adult, more than aloof tolerance might not be in the cards.

I think I would start by never letting the two interact offleash unless the Lab has already played for a while and is getting tired and calmer, then reward the calm behaviour heavily and see if you can build tolerance in the collie that way, by showing that the hooligan can in fact behave.

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It's not easy for a monkey to think like a dog

My cat Tijgje shows off his tricks

Hi - sorry to not have come back to you sooner. I am probably not the best person to ask for advice, but what we did with Barney in the end was took him to see a specialist in dog behaviour (at our local vet - see if yours offers this service). She taught us to ignore bad behaviour but reward good behaviour - so if Barney met another dog in the park and showed no aggression we gave him a treat. She advised NOT to punish him when he showed aggression as this might make him worse - because the growling was a form of anxiety, so if we were to smack him he would become even more anxious and may eventually cut out the growling and proceed straight to the next stage which could mean a bite. So we make a fuss of him when he is around other dogs to reassure him that everything is OK. He is much better these days. I also have a good book "How to talk to your dog" which helps us to understand how dogs communicate and respond to signals. I hope you manage to resolve your Finn's behaviour as I am sure you will.

Thank you for taking the time and trouble to reply to my thread. Things are better than they were with Barney as I did visit a dog behaviour specialist via our local vet. She more or less said the same, that these 2 dogs would never be friends. But as it happened the lab got too big and boisterous even for my sister and her family and they decided to have him re-homed. They now have a miniature schnauzer who is as good as gold.

We have followed the advice we received and have spent much time trying to comfort Barney when there are other dogs around and giving him treats when he is good with them. We don't chastise him if he does growl as the behaviourist advised this might actually increase his anxiety and make his behaviour worse. Greetings are usually OK these days and many have said he is a much nicer dog. The only problems we get now are if Barney is in the same room as another dog and all the teeth baring and growling still prevails if the other dog comes too close. He is not good with puppies as they do have a habit of getting in his face and jumping all over him, so occasionally he has a snap if they don't take the hint. My sister's new dog is a lot better as he will at least back off, if Barney signals to him to buzz off and will then sit away from him. But they didn't want to invite us over for Christmas this year because they knew we would want to bring Barney and said they didn't want him in their house if he was going to growl at their dog - quite upset me really but I could understand their viewpoint. It also means holidaying together might be difficult so we still have a few problems to overcome.

I think there is an issue of territory - as soon as Barney is in a room with us he becomes anxious and protective of us if there is another dog nearby. Unfortunately, his behaviour still makes us quite tense and if he won't let up we have to put him in the car on his own (or in another room on his own) whereas what I really wish is if he could just be more tolerant when other dogs are present. But thanks again for your advice.