Aspen Veterinary Resources Pen-Aqueous®

Potent antibacterial agent which is effective against a variety of pathogenic organisms, chiefly in the gram-positive category. Recommended for the treatment of bacterial pneumonia (shipping fever) caused by Pasteurella multocida in cattle and sheep, erysipelas caused by Erysipelothrix rhusiopathiae in swine and strangles caused by Streptococcus equi in horses. 

Milk taken from treated dairy animals within 48 hours after the last treatment must not be used for food.
Discontinue use of this drug for the following time period before treated animals are slaughtered for food:
Cattle - 4 days    Sheep - 6 days   Swine - 8 days