A portable enclosure for capturing and retaining an animal features a pen carried alongside an ATV, a front opening in the pen, and at least one door movable between open and closed positions at the front opening. A lock member is carried above the front opening, and is displaceable into and out of a locking position engaging the door. A rotatable actuation member resides overhead of the lock member and is operable by a foot pedal to draw the at least one lock member upwardly out of the locking position to unlock the door. The same lock member acts in both the open and closed positions of the door by way of cooperation with strike plates on the door panel and an extension member projecting therefrom. The strike plates are shaped to return the lock member to a ready state for automatic locking during opening and closing of the door.
