Hey,
I'm not saying that you shouldn't look into this situation, as others have suggested, but I just wanted to say that that dog isn't too much skinnier than my baby. I can see probably 5 or 6 of Saschas ribs, and some of her spine and her hip bones stick out too. And she's definitely not neglected. She gets 4 cups of solid gold a day plus pumpkin and treats. Now, granted she's on'y 9 months old, but her mom was three and a half last time I saw her and looked pretty much the same. Cleo lives on a horse farm, so she spends all day every day chasing horses around fields, so she stays skinny regardless of what she's fed.
I'm not saying that dog looks right, and it's not good that his owner thinks he does(judging by her comment about how boxers don't fill out till the age of 4 or 5) but it's also not a certain fact that he's abused. I feel like I'm going to get yelled at for posting this, but I just felt like I should point out another viewpoint, especially since every time I take Sascha anywhere I get criticized by strangers for how skinny she is.