A safety latch mechanism for anchoring an open center gate in a livestock trailer includes a spring-biased post attached to the center gate's free edge having a lifting lever at an upper end. An arcuate track embedded within the truck bed traces the path of the center gate's free edge when moving between a fully opened and a fully closed position. The track includes a series of juxtaposed, segregated compartments for receiving a lower end of the post. Accordingly, the center gate can be locked in a multitude of angular positions between the fully open and fully closed positions by lifting the lever and releasing it into one of the compartments.