Doraemon Movie 26: Nobita no Kyouryuu 2006

Nobita discovers what appears to be a fossilized dinosaur egg and, with Doraemon's gadgets, succeeds in hatching it. The newborn plesiosaur, Pisuke, quickly becomes precious to him, but raising a prehistoric creature in modern Japan cannot remain a secret forever.

When Nobita takes Pisuke back to the age of dinosaurs, hunters from the future threaten the creatures of that era and separate the friends from the safe return they expected. Doraemon, Nobita, Shizuka, Gian, and Suneo must cross a vast prehistoric world, protect Pisuke from those who would capture him, and find their own way home.