600269 Disclosed is a delivery device when used for the treatment or prevention of mastitis in a mammary gland of a non-human animal wherein the oxygen level is lower than that would be physiologically normal, due to infection, wherein: the delivery device includes an extended acting oxygen generating system wherein the oxygen generating system includes a hydrogen peroxide generation system (and which may include a compound such as sodium percarbonate, urea peroxide, magnesium peroxide or calcium peroxide and combinations thereof) wherein the delivery device also includes a substrate for the hydrogen peroxide generation system in the form of oxygen, peroxide, glucose or other sugars, thiocyanate, iodate, or potassium iodide, or a halide selected from the group consisting of iodides, chlorides, and combinations thereof wherein the delivery device may further include glucose oxidase and/or at least one additional substrate of the Lactoperoxidase system or equivalent enzymatic system able to produce antimicrobial agents characterised in that the delivery device is configured to separate two or more components present in the delivery device prior to administration to a non-human animal to prevent oxygen generation until administration and thereafter, and when the two or more components come into contact during administration to the site of infection to provide oxygen generation over a time period between 30 seconds to 14 hours following administration to the non-human animal.
