My Boxer Jack is Skinny, I get questions like, do you feed him and everything else. we have 3 other dogs and the are considered over weight. He eats, we have taken him to the vet, clean bill of health except for weight. I know he eats because he gets fed separate. I don't know what to do at this point
I recently switched my dog to annamaet dog food that has 26% more protein in it to help her gain some pounds. She's so active that she doesn't keep weight on!
Before doing this we did have the vet run tests to be sure she was getting the nutrients from her food like she should. Perhaps your pup is not digesting properly- could be something to ask the vet!
Try feeding him highly calorific or high-fat food. Maybe even increase the number of meals he has a day. But if he still doesn't gain weight, it's okay. Just like there's a large variety of body sizes and appetites in humans, your dog may not have a big appetite. Unless your dog is extremely underweight, like twenty pounds below the average or so, there's no need to worry.
Just like us humans, dogs's dietary needs are specific. The two dogs that are overweight and the underweight dog need different food and amounts. Food with less fat and food wood with more fat, until desired weight is achieved. All meals acurrately measured according to directions on bag, and done approximately at the same times, twice daily. I have been using a dry food that is grain free and full of protein and fatty oils from fish, among other things like vegetables, seeds, herbs and vitamins.
He's afraid to eat. He is not the dominant one at home, that's for sure. Get him wet food. The best kind and then mix it with dry food. That should plump him up. But you'll still have to watch him as he eats. He won't get to eat unless you're around.