Mycoplasma bovis:

Mycoplasma bovis is a bacterium that causes a range of diseases in cattle including mastitis that doesn’t respond to treatment, arthritis, pneumonia and late-term abortion. 

Mycoplasma bovis is mainly spread by direct contact between infected animals and on equipment that has been used on infected animals, e.g. used for milking, artificial insemination, veterinary procedures.  It spreads through bodily fluids including mucus and vaginal secretions. It is not thought to be transmitted in urine or faeces. It is not windbourne or spread in water.  It is a relatively slow moving disease.

For more information see the links below:

Dairy NZ - Mycoplasma - everything you need to know