He does look a little underweight but nothing serious, it's best to keep them a little skinny as they're growing to keep from putting too much strain on their joints.
What are you feeding him and how much?
Jasmine - Female Miniature Poodle - born Aug 15, 2010
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Koda & Zazu - 5 year old male cats
Alex - Male Cocker Spaniel (rescue) - RIP Cuddlebug 2007-2010