Veterinary methods for administering nitric oxide (NO) in a plasma state to a treatment site associated with an animal are disclosed. A discrete stream of matter is placed in a plasma state, in which the stream has, as part of its content, a desired concentration of NO. The discrete stream of matter is directed at a site of action associated with an animal to achieve a therapeutic result. A method for decontamination of veterinary equipment with NO in a plasma state is also disclosed.