As most dairy farmers would be aware, MPI has confirmed the presence of the bacterial disease Mycoplasma bovis in a South Canterbury dairy herd. The disease diagnosis was confirmed on July 22 and made public on July 24-25. This disease, while present in other dairying countries such as the US, UK, Ireland and Australia, is new to New Zealand.

Mycoplasma is a bacterial disease where diagnosis is not via the routine microbiological methods (such as standard milk culture) due to the nature of the organism. It affects mostly calves and adult cattle. Mycoplasma does not cross-infect humans from animal sources (not a zoonosis) and it does not survive milk pasteurisation.
While we do not yet know the specifics around how this specific outbreak is being managed, it is worth briefly outlining aspects of surveillance for this disease that can then be “front of mind” for all farmers. Hallmarks of the potential presence of Mycoplasma in a herd are: 

• Clinical mastitis in multiple quarters in the same cow and increased numbers of clinical mastitis unresponsive to treatment 
• Cows with mastitis that appear to have a lot of milk but give very little 
• Cows with mastitis that is also associated with arthritis in adult cows 
• Concurrent increased ear and joint infections in calves or an increase in calf pneumonia 

Mycoplasma is a highly contagious organism in both calves and adult cattle. In all dairying countries where it has become established, it is associated with expanding herds where cattle, including young stock, are traded. A test (PCR) is available for use on bulk vat milk to assist in biosecurity where herds are expanding.

Members of Anexa FVC and Cognosco have connections with overseas based veterinarians and researchers who are experts in mycoplasma control. These networks are being activated in light of this news so that our veterinary team is fully prepared. Should you have any concerns or questions about this disease please contact a member of the veterinary team.

Dr John Penry recently joined the Anexa FVC team. John has been involved in the veterinary and dairy industries for over 25 years as a Veterinarian, Advisor and Researcher.