My dogs name is duke and he is not gaining weight why ?

Do you know how he was mistreated? Are you feeding him what was recommended by the shelter or previous owner? How old is he, what kind of dog is he, and how long have you had him?

We had a dog like that. It was as if the dog were asking permission to eat. Slowing we handfed the dog morsels until we gained his trust. Loving him and telling him it was OK he finally came around. He still will stand by his bowl and look up as if to ask if it is OK but this is a short lived moment before he is eating. He does eat slowly but he eats. We add treats now which he may or may not refuse. We let him decide. He chose one family member to stay at the side of most which seems to bring him comfort. He allows all to pet and love him but has adopted the one to be his ultimate trusted keeper.

It is also important to make sure he has been checked for heartworm and other ailments due to mistreatment. Worming and hygiene for the dog in a gentle manner also improve his health. If that does not work, he may have an issue the vet can resolve.

Belgia, wonderful posts, but I do have to add, and more information from the OP is needed to determine this, that she didn't say her dog wasn't eating. She said the dog wasn't gaining weight.

To me this sounds like a health issue. There are many things that could be wrong that could cause a dog not to gain weight. It could be a thyroid condition, it could be a tumor, it could be worms. There's no way for anyone on the internet to be able to diagnose, so the last suggestion, to see a vet, is really the only option.

So very true.