Bovine Mastitis

Mastitis continues to be the most costly and common disease of dairy cows and it is the predominant reason for antibiotic usage in dairy herds.

It has a negative impact on milk production and quality, animal welfare, and farm economics; overall, healthy animals are more efficient milk producers. The mastitis research group in Department of Production Animal Medicine includes Professor Päivi Rajala-Schultz, Suvi Taponen, Mari Hovinen, Heli Simojoki and Riitta Niemi. On-going research projects focus on dry cow management, antimicrobial resistance and virulence of different mastitis causing staphylococci and streptococci, and on occurrence teat diseases.

Drying-off practices in Finnish dairy herds

The aim of this epidemiologic research is to identify optimal drying-off practices to maintain good udder health and productivity while implementing prudent use of antibiotics. Susceptibility of cows to mastitis particularly during the dry period puts emphasis on antibiotic dry cow therapy (DCT) as an important part of mastitis control. No previous research exists on Finnish dry cow management and DCT use. Also from an international perspective, by far the most puzzling question is how to select the cows to be treated at dry-off considering udder health, profitability, antimicrobial resistance, and sustainability concerns.

The research utilizes questionnaire information and retrospective Dairy Herd Improvement information to determine both herd- and cow-level associations between milk somatic cell count (SCC), milk yield, and different farm and cow characteristics with a special focus on the usage of antibiotics at dry-off. Additionally, an important part of the research is a clinical field trial, which contributes to finding criteria for identifying cows that need and benefit from dry cow treatments.

The research, lead by Prof Päivi Rajala-Schultz, is funded by the Finnish Ministry of Agriculture, the Finnish Veterinary Foundation, Valio Ltd, Vetcare Ltd, and Orion Pharma.


Niemi R.E., Hovinen M., Rajala-Schultz P.J. 2022. Selective dry cow therapy effect on milk yield and somatic cell count: A retrospective cohort study. J Dairy Sci. 105:1387–1401.

Niemi, R. E., M. Hovinen, M. J. Vilar, H. Simojoki, and P. J. Rajala-Schultz. 2021. Dry cow therapy and early lactation udder health problems - Associations and risk factors. Prev Vet Med 188:105268.

Niemi, R. E., M. J. Vilar, I. R. Dohoo, M. Hovinen, H. Simojoki, and P. J. Rajala-Schultz. 2020. Antibiotic dry cow therapy, somatic cell count, and milk production: Retrospective analysis of the associations in dairy herd recording data using multilevel growth models. Prev Vet Med 180:105028.

Vilar, M. J. and P. J. Rajala-Schultz. 2020. Dry-off and dairy cow udder health and welfare: Effects of different milk cessation methods. Vet J 262:105503.

Vilar, M. J., M. Hovinen, H. Simojoki, and P. J. Rajala-Schultz. 2018. Short communication: Drying-off practices and use of dry cow therapy in Finnish dairy herds. J Dairy Sci 101:7487-7493.

Heikkilä. A.-M., Niemi R.E., Hovinen M., Rajala-Schultz P.J. 2022. Economic perspectives on blanket and selective dry cow therapy. Accepted for publication in Agric. Food Sci, September 2022.

Niemi R.E., Hovinen M., Rajala-Schultz P.J. 2022. Selective dry cow therapy — Clinical field trial on the prevention and cure of intramammary infections, in preparation.

Nordic mastitis researchers’ network

With Prof. Päivi Rajala-Schultz in the lead, Nordic researchers working on bovine mastitis and udder health are enhancing their collaboration and building an active network, supported by NKJ (Nordic Joint Committee for Agricultural and Food Research) networking funds to tackle the challenges of mastitis together. The long-term goal of such collaboration is generation of new science-based knowledge in joint Nordic research projects on sustainable and cost-effective management and mastitis control practices which will help in prevention and control of the disease.

The funding for the network has allowed the network leaders (Professors Päivi Rajala-Schultz, Tariq Halasa (Denmark), Ane Nødtvedt (Norway) and Karin Persson Waller (Sweden) to organize 2-day seminars/workshops for the Nordic mastitis researchers, one in Uppsala, Sweden in September 2018, and another one in Tuusula, Finland, in September 2019. The theme of the first workshop was “Nordic mastitis research – on-going projects and research needs”, with 43 participants. The theme of second workshop was “Mastitis treatments and drying-off practices”, with 31 mastitis researchers, dairy advisers or others attending. The third seminar was held in the spring of 2021 as a webinar and the fourth seminar in 2022 was an on-site meeting in Copenhagen, Denmark, but it was possible to attend also online. The fifth seminar will be held in Uppsala, Sweden, in September 2023.


Rajala-Schultz, P., K. Persson Waller, T. Halasa, and A. Nodtvedt. 2019. Selective approach to dry cow therapy. Vet Rec 184(1):29-30.

Rajala-Schultz P, Nødtvedt A, Halasa T, Persson Waller K. Prudent Use of Antibiotics in Dairy Cows: The Nordic Approach to Udder Health. Front Vet Sci. 2021 Mar 5;8:623998. doi: 10.3389/fvets.2021.623998. PMID: 33748209; PMCID: PMC7973009.

Virulence, antibiotic resistance and epidemiology of mastitis causing pathogens and occurrence of teat diseases

The bovine mastitis group has also other on-going projects on different aspects of specific mastitis causing pathogens and teat disaeses. These projects focus on antimicrobial resistance and virulence of different mastitis causing staphylococci and streptococci. A survey on teat diseases was conducted among dairy farmers with a special interest in the occurrence of ischaemic teat necrosis in first lactation animals.