A mycoplasma is an organism between a bacteria and a virus, it has no cell wall so antibiotics are mainly ineffective.

Mycoplasma infections are controlled by biosecurity, it is spread through contaminated antibiotics, syringes, milking units, common cloths, etc.

Teat dipping is a good preventative measure; infected cows are isolated and culled. The infection is often acquired in well managed herds and the source is nearly always from bought in animals.

Control of contagious mastitis.