Ushi Ushi no Mi, Model: Bison

The Ushi Ushi no Mi, Model: Bison (ウシウシの実 モデル：野牛（バイソン）) is a Zoan-type Devil Fruit that allows its user to transform into a bison hybrid and a full bison at will. "Ushi" is Japanese for "cow" or "ox", and bison are part of the same subfamily as cows. In the 4Kids dub, this fruit is simply called the Ox-Ox Fruit, while the Viz Manga calls it the Ox-Ox Fruit, Bison Model and the FUNimation dub calls it Ox-Ox Fruit, Bison Form. It was eaten by Dalton.

Strengths and Weaknesses
The major strength this fruit grants, as demonstrated by Dalton, is that the user is granted two extra forms to transform into: a full bison form and a human-bison hybrid. This gives him enhanced physical capabilities, similar to a real bison's or even more. Using this as an advantage, Dalton possesses incredible strength and speed, to the point of creating afterimages.

This fruit has no known weaknesses, aside from the standard Devil Fruit weaknesses.

Usage
This fruit's added physical capabilities allowed the user to become much more deadly when fighting. Dalton has used the fruit's powers primarily for combat purposes.
 * Fiddle Banff (フィドル突撃（バンフ）): Dalton transforms into his bison-human hybrid form and then charges at his opponent at incredible speed, slashing them with his spade and slashing them swift and strong. He can take out multiple opponents with this technique. In the Viz Manga and FUNimation dub, this is called Fiddle Bam. This was first used on some of Wapol's soldiers.

Translation and Dub Issues
In the 4Kids dub of the anime, the fruit's name was changed to Ox-Ox Fruit in order to cater to an English-speaking audience. While this is technically correct, due to the lack of any words suggesting otherwise, the name in the 4Kids dub technically implies that Dalton turns into an ox instead of a bison. While the words "ox" and "bison" can sometimes be interchangeable, they usually refer to two different breeds of bovine. The Viz Manga and FUNimation dub avoid confusion by calling it the Ox-Ox Fruit, Bison Model and Ox-Ox Fruit, Bison Form, respectively.

Trivia

 * This Devil Fruit ability was never seen or mentioned during the Episode of Chopper Plus film.
 * This is the first Zoan ever to appear in the series.