Yep, I've recently had the same issue with my Shih-Tzu/Poodle mix (in my profile pic). Muffin typically weighs about 8 1/2 pounds, but at her last visit was just under 10 pounds. Doesn't sound like a lot, but that's a gain of 17% of her original body weight! The only thing we've changed is that she was getting more table scraps (now that we eat more nutritious dinners, there's more chicken/salmon/etc. which she loves). Unlike her regular dog food (which she "grazes" and eats only when she's hungry), she ALWAYS eats the table scraps -- so it's definitely more calories over the course of the day than she needs. We've instituted a new policy -- NO table scraps! She's prone to joint issues, so we need to keep her at a healthy weight (like "mother" like "daughter"