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I need some advice on putting some weight on my frenchie. He's a male, unaltered, 12 months old. He's weighing in at about 23lbs now, and he's healthy, no breathing or severe allergy issues to date. He's currently eating Wellness brand dog food to the feeding instructions on the package but he's really boney and skinny. I know he's a good weight, the vet said he looks good and that unaltered male…