I find that a canned food can put weight on fast and there are many grain free, good products to choose from. I mix canned and my dry which is Orijen adult and have a skinny boy that is hard to keep weight on and that does the trick. I also supplement with chicken or hamburger, etc. and that gets him interested in his bowl of food! Not sure if you have an issue with your dogs not wanting to eat or just hard to keep weight on. Be careful when transitioning, you can upset everything if you go too fast. Good luck!
