I believe what is happening is the Sheltie really doesn't know how to interact with other dogs. I know you are probably saying NO JOKE, we already know that! The problem originated when the sheltie was a baby. The most critical time in a pups socialization with other dogs is between 4 and 16 weeks. I am guessing that this pup was originally quite aggressive in play in the whelping box. The other pups probably put him in his place one time when he was too aggressive and he developed a fear. At this point the other pups concentrated on play with the others in the litter because he wanted to avoid getting beat up. I judge this by your comment that he got so wound up that he almost took your thumb off. In the whelping box, when one pup doesn't learn to be easy the others will not play with him. I had this happen to a little golden girl in our litter.

When this does occur the new owners need to be aware of it and told up front. Two things can occur after the new owners take the dog home. 1. The dog becomes very timid for fear that no one wants to play or 2. the pup becomes so dominant in the new territory that no one else is allowed to enter.

New owners need to realize that there is a short window of opportunity here for helping the pup get over this situation. And by the way.... when a breeder realizes this is happening in the whelping box, they should place the pup before 8 weeks or work specifically to teach the pup how to interact with the rest of the litter. This is the only situation where I would recommend the dog be placed before 8 weeks since the longer it continues the worse it is for the pup in the long run if the breeder doesn't recognize it. We had to work diligently with our little girl and made sure the new owners knew of the situation so they could continue to help her. She is a very confident dog today around all other dogs except a couple of her littermates. When she came over for their birthday party she showed a timid side that the owner said she never sees anywhere else. Dogs have a very long memory!

Well none of this helps you now since the sheltie is older. Just trying to get you to understand why the dog may be this way. Basically the prime window of opportunity passed a long time ago. Another point to realize that the older sheltie who was 14 didn't reinforce any play with pup so he actually has two strikes against him. Poor fellow!

But there is possible conditioning that can occur to perhaps help the sheltie to understand play. The owners will need to realize this will take a lot of counter conditioning if this is something they really want to occur. Perhaps they are happy with the way things are and could care less if their dog plays with the Poodle.

Some things to try. If the dogs have reign in the entire office, try putting them together in a closed off area. X-pens offer great space confinement. By being together in close quarters they will learn that they are the same species and are both favored the same since they are both confined to a smaller space. Leave some Jolly balls or tug ropes in the area for the dogs to play with. Not taking the dogs out of the area play tug or fetch with each one. If one doesn't want to play, play with the other. After a few days you can take a tug rope and put it in each of the dogs mouths and let them start tugging. It may be something they need to learn to do so be patient. Tug is the best game for two pups to play together.

Basically these two need to minimize human intervention and realize they are both in the same boat and need to rely on each other for company. They need to deveope their own rules on being together. This may be something the owners want to achieve or it may be something they just want to say "forget it". They may be comfortable with their pup the way it is. After all this is just a work situation and not a situation where these two dogs are together all the time.

I have to be honest, at this point if the sheltie were my dog, I wouldn't worry about it. The poodle would just have to adjust. After all the sheltie is in mid life and this may end up putting additional stress on him. While it would be nice to see him play with another dog, at this point in life is it really necessary? Only the owner can determine this for sure. But if they do, then start with putting them together in the confined space and letting them adjust to each other. More so the Sheltie than the Poodle.

Sorry this was so long!