Unfortunately I think Buck the dog is CGI. The commercials clearly show he is not a real dog. Guess they didn't want to spring for a dog trainer!Buck is named after the canine hero, in Jack London’s “Call of the Wild”. Mostly for sentimental reasons as it was a book my dad read aloud to my sister and me when we were kids. Harrison Ford is in a new movie version of it. Every time I see the trailer, I image Buck in place of the St. Bernard-ish looking star and laughing that none of the scenes would go as planned if he was the lead.