Dairy cow mastitis campaign starts to yield results

17th Jun, 2025

- 30% of Mastatest submissions identified no bacteria or bacteria which would not benefit from antibiotics -

New data from CVS Farm’s recently launched dairy cow mastitis campaign has revealed that approximately 30% of its Mastatest submissions have either identified no bacteria or bacteria which do not benefit from antibiotic use.

As a result, farmers have been encouraged to treat affected cows with Non-Steroidal Anti-inflammatories (NSAIDS) while awaiting their Mastatest results, then use the results to administer an appropriate treatment for their cow’s mastitis - where over 1 in 4 cases do not actually need antibiotic therapy[i].

Launched in July 2023, CVS Farm’s dairy cow mastitis campaign – in operation across 15 of its farm practices  UK-wide - aims to improve the role of farm vets in dairy cow mastitis decision making - using culture and sensitivity testing.

The project uses diagnostic testing to inform appropriate treatments and management decisions - and to target antibiotic treatment only where indicated. It is hoped the project will reduce the use of antibiotics, lower their systemic use, and help to guard against antimicrobial resistance in the future.

Bovine mastitis is an inflammatory response of the udder tissue in the mammary gland caused due to a physical trauma or microorganism infections. It is considered the most common disease leading to economic loss in the dairy industry due to reduced yield and poor quality of milk[ii].

Less than half of mild to moderate clinical mastitis cases are likely to benefit from antibiotic therapy[iii][2]. It is vital to differentiate them from those that will benefit from prompt treatment. A major barrier to achieving this has been the need to send milk samples off to a lab, resulting in a turnaround time of 48 hours or more, and a delay in treatment.

To overcome this barrier, CVS has invested in Mastatest technology for all 15 of its farm practices. Its farm practices are now able to perform in-house milk sample culture and sensitivity testing in 20-24 hours – to identify if pathogens are present and which, if any antibiotics are most suitable as a treatment.

Emails containing each set of Mastatest results are sent to CVS’ vets and their farmers as soon as they are produced. Treatment plans - predetermined by the vet and farmer when initially setting up the Mastatest machine - can then immediately be actioned. A live online dashboard also allows both parties to view summary data across all samples tested.

CVS’ Farm Vets started to introduce the new dairy cow Mastatest quality improvement project in July 2023. The group has now run nearly 700 clinical samples and 150 high cell count milk samples. From clinical case samples tested so far, 34% had either had no bacterial growth or E.coli infection. It is likely that these cows would go on to self-cure without the need for antibiotics.

S.uberis has been found in 16% of clinical case samples to date, requiring antibiotic treatment. By looking at the results of Mastatest antibiotic sensitivity testing for S.uberis, CVS Farm practices have been able to move away from broad-spectrum category C antibioics to narrow spectrum category D penicillins, to further safeguard antibiotic use.

Steven Carragher, Farm Quality Improvement Lead at CVS Farm, said:

Quote starts

“Bovine mastitis is a significant cause of financial loss to dairy farmers. Our Farm practices want to provide practical and effective day-to-day care. The rapid Mastatest technology and support we’ve set up in every practice is proving to quickly result in the right treatment for individual cases of mastitis. The programme is also a significant step towards reducing unnecessary antibiotic use, helping to safeguard against antimicrobial resistance and aiming to increase the health, welfare and productivity of cows on dairy farms.”  

Quote ends

The Mastatest campaign has been a team-wide project within CVS Farm practices. Whilst farm staff and vets have taken samples on the farm, administration staff and vet techs have set up and run the samples on Mastatest machines within practice.

CVS Farm is taking a ‘One Health’ approach to clinical improvement and developing practical projects to address related challenges, such as antimicrobial resistance and improving animal welfare. Every practice has appointed a vet to be a Practice Quality Improvement Lead, who collaboratively; brainstorms how to overcome challenges; develops ideas for clinical improvement; identifies the resources and technology needed to implement each project; and advocates for programme delivery within a practice’s team.

CVS Farm division has over 120 vets in 15 modern farm specific practices nationwide. Its practices offer a comprehensive range of services, with a focus on helping our clients prevent disease and maximise efficiency of production on their farms. The CVS Group operates across small animal, farm animal, equine and laboratories, with over 500 veterinary practices and referral centres in the UK and Australia. In the last five years the company has invested nearly £80 million in its sites, facilities and equipment, in addition to industry leading training and support, to give the best possible care to animals. For further information on CVS visit www.cvsukltd.co.uk .

[i] Roberson JR. Establishing treatment protocols for clinical mastitis. Vet Clin North Am Food Anim Pract. (2003) 19:223–34, viii. doi: 10.1016/s0749-0720(02)00071-3 [DOI] [PubMed] [Google Scholar]

[ii] Bovine mastitis: risk factors, therapeutic strategies, and alternative treatments — A review - PMC (nih.gov)

[iii] An Investigation of the Impact of Intramammary Antibiotic Dry Cow Therapy on Clinical Coliform Mastitis - ScienceDirect