Oolong is a shape shifting pig in Dragon Ball. He can hold any form for 5 Minutes at a time. He is also a pervert, and enjoys collecting women's underwear and trying to see Bulma naked. Oolong's rival is Puar. His role in the series starts out as a very prominent main character in Dragon Ball, and gets a bit smaller by the beginning of DBZ, and even smaller by the end of DBZ. By DBGT, his role is reduced to a bit part.
When Dragon Ball was first adapted into English in 1989, he was voiced by Dave Mallow. This dub was test marketed on several stations, and went under the radar. It was canceled after a small amount of episodes and movies were dubbed. In this dub, Oolong was renamed Mao-Mao.
Oolong was voiced by Alec Willows for most of the early Vancouver voice productions for the Dragon Ball franchise. This included the 1995 English dub of Dragon Ball, the Funimation/Saban adaptation of Dragon Ball Z, the second DBZ movie, and the edited TV version of the third DBZ movie.
Doug Parker initially filled in as Oolong for the uncut version of the third DBZ movie. He also completely took over the role for Oolong's remaining appearances in the Westwood/Ocean dub of the Trunks Saga onward.
For an alternative dub of Dragon Ball produced in association with Blue Water Studios in Calgary, Canada for broadcast in the UK and Canada, Oolong was voiced by Corby Proctor.
For most of Funimation's in-house Dallas voice productions (which covers pretty much the entire franchise), Oolong has been voiced by Brad Jackson.
Mark Britten filled in the role briefly in the beginning of Funimation's in-house dub of DBZ when Brad Jackson was unavailable. Brad has since redubbed Britten's voice for the recent remastered release.
In most current media (such as Dragon Ball Z Kai and the recent dub of Curse of the Blood Rubies), Oolong is voiced by Bryan Massey for Funimation Entertainment.
For the AB Groupe English dubs of some of the movies that aired in European markets and were recorded in France (AKA "The Big Green dub"), Oolong appears, and is voiced by David Gasman.