Dudley, appropriately, leads a dog's life: good food, leisure time, kind master. But he's inexplicably sad and runs away to discover what he's missing. He finds camaraderie with pigs and turns into a ``pig-dog'' of sorts; seeks haven with a donkey and takes on its attributes; finally, he takes up with a rabbit and gains long ears. Hunting season puts an end to that friendship and Dudley returns home, where another dog has replaced him. A dog friend, Dudley realizes, is what he needed all along. For a book with a look as gentle as a lamb—the pigs are delightful hedonists, the donkey might have carried Mary to Bethlehem—the stick-to-your- own-kind message is unsettling. Positive notions about individuality and assimilation become jumbled with negative ones; it's probably too much for young children to sort out. (Picture book. 5-8)