Hexamethyl-p-rosaniline chloride (HRC), also known as crystal violet or gentian violet, is a water soluble, triphenylmethane dye with bacteriostactic, fungistatic and antihelminthic activities. It has a wide range of uses, from a treatment in humans to an additive for poultry feeds. In the poultry industry, this compound has been proven as a fungicidal agent in feed, a selective bactericide against gram-positive bacteria, and has demonstrated inhibitory effects against the activity and infectivity of various strains of viruses including Newcastle disease and fowl-plague virus. At normal inclusion rates (0.5 to 1 kg/MT final feed), commercial products such as GV-11 (Naremco, Inc.) failed to be detected in broiler meat. High levels of consumption of gentian violet can be toxic to animals, with the single dose LD50 for GV-11 determined to be between 2.5 and 5.0 g/kg body weight.
