A portable, towable livestock sprayer establishes a portal through which livestock move. A rigid, frame includes a removable tongue for connection to the draft vehicle. A pivoted, wheeled subframe hinged to the frame is switched between deployed or retracted orientations. The tongue fits to the subframe and functions as a leverage tool. With the sprayer properly positioned adjacent a livestock gate, a shroud assembly is deployed. Photo-eyes determine the presence and direction of travel of animals being sprayed. A pump system controls solution. The shroud transforms between a stable, compact transportation orientation, and a deployed orientation conformed to the required dimensions. Separate, extensible shroud wings are folded together during transportation, or separately deployed on opposite sides of the sprayer to block escape routes. Each wing comprises an inner section adapted to be removably coupled to the frame, and an outer section slidably telescoped to the inner section enabling width adjustments.