CAT and Mycoplasmoides infection: It has been suggested that the pathogenesis of mycoplasmosis comprises the following sequence of events: (a) adherence of mycoplasmas to host cells; (b) generation of superoxide and hydrogen peroxide by the microorganisms and their introduction into host cells; (c) irreversible inhibition of host cell catalase by intracellular reactive-oxygen-species accumulation; and (d) oxidative damage to vital cell constituents [18,19,22].