Otie is a diminutive form of Otis: soft, affectionate, with the playful -ie suffix that owners add to humanize and warm up a name. With 28 registry records it's almost certainly a call-name variant that got registered directly: owners who call their dog Otie at home but whose official name is probably Otis.
The Otis Nickname Trail
Otis is a well-performing pet name in its own right, most famous as the dog in the Japanese film Milo and Otis and in various pop-culture contexts. The -ie diminutive Otie is what affectionate owners actually say when they're being warm rather than formal. It follows the same pattern as Archie for Archibald, or Louie for Louis; the official name gets softened in daily use.
Sound and Warmth
OH-tee is two syllables, fully soft, with no hard consonants anywhere in the name. It's an extremely warm, gentle call-name sound that suits good-natured, easy-going dogs and cats. The human name Otis carries mid-century American warmth in its full form.
The Counter-Reading: No Independent Identity
Otie doesn't exist as a proper name; it's entirely a diminutive of something else. If you want the softened sound in official contexts, it works; if you want a name with cultural depth, look at Otis instead. Browse pet names.