The mastitis research group in Department of Production Animal Medicine includes Professor Päivi Rajala-Schultz, Mari Hovinen, Riitta Niemi, and Suvi Taponen. Research projects focus on dry cow management, antimicrobial resistance and virulence of different mastitis causing staphylococci and streptococci.
Ministry of Agriculture and Forestry of Finland has awarded a 3,5 year funding to a research project focusing on Streptococcus uberis mastitis, its prevalence, risk factors, and prognosis. The research also assesses genetic variation, antibiotic susceptibility and contagiousness of the causal bacteria in Finnish dairy herds.
Mastitis-causing bacteria have traditionally been considered either contagious or environmental. Streptococcus uberis bacterium is a common cause of environmental mastitis, but it can also cause contagious outbreaks. Transmission and spread of Str. uberis may be herd specific. The number and importance of environmental mastitis pathogens has increased at the same time as the incidence of contagious mastitis has decreased. Cure and treatment response of Str. uberis mastitis appears to have weakened in recent years. No Finnish research-based information is yet available on this topic, however.
The objective of the project is to produce practical information on the genetic variability, antibiotic susceptibility, and contagiousness of Str. uberis strains. Additionally, the study evaluates Str. uberis mastitis prevalence, risk factors, prognosis, and milk-yield losses. By recognizing the characteristics of Str. uberis mastitis we will be able to enhance dairy cows’ good udder health and well-being, prudent antibiotic usage, and antibiotic resistance prevention as well as support high-quality milk production and the economic and ethical sustainability of dairy farming.
The project will be conducted in collaboration between the University of Helsinki, Department of Production Animal Medicine, and the Finnish Food Authority. Riitta Niemi, PhD, DVM, is the principal investigator of the project. Muusa Takala, DVM, is conducting her doctoral research within the project. Prof. Päivi Rajala-Schultz, Tiina Autio, DVM, PhD, and Ahmad I. Al-Mustapha, DVM, PhD, are members of the research team.
Publications
Takala, M. M., Dohoo, I. R., Rajala-Schultz, P. J., Autio, T. J., & Niemi, R. E. (2026). Herd-level factors associated with Streptococcus uberis, Staphylococcus aureus, and Streptococcus agalactiae mastitis: dairy herd data from 2013, 2018, and 2023. Preventive Veterinary Medicine, 106937.
The ongoing research studies the validity and utility of the quantitative PCR method in diagnosing bovine mastitis. In Finland, qPCR is well established as a routine method of microbiological diagnosis of intramammary infection, although bacterial culture remains widely used worldwide.
The aim of the study is to compare the qPCR method and conventional bacterial culture in detecting mastitis-causing pathogens in quarter-milk samples from dairy cattle. The study evaluates the sensitivity and specificity of qPCR in diagnosing common mastitis-causing pathogens compared to conventional bacterial culture in different clinical presentations.
In addition, the study examines the utility of qPCR in assessing survival prognosis after coliform mastitis. Mastitis caused by the coliform bacteria Escherichia coli and Klebsiella spp., is often severe, and effective treatment options are limited. The aim is to evaluate the association between pathogen-specific cycle threshold (Ct) value and survival after coliform mastitis.
The project will provide a better understanding of the suitability of qPCR for diagnosing mastitis-causing pathogens and research-based information supporting diagnostic and treatment decisions for improving udder health in dairy cattle. By investigating survival in relation to Ct values, the study could provide clinically applicable information for practical use in assessing prognosis of cows suffering coliform mastitis.
Riitta Niemi, PhD, DVM, is the principal investigator of the project. DVM Marianne Huuskonen is conducting her doctoral research within the project. Mari Hovinen, PhD, DVM, and Prof. Päivi Rajala-Schultz are members of the research team.
Research outputs
Huuskonen, M., Hovinen, M., Rajala-Schultz, P., & Niemi, R. (2026). Using quantitative polymerase chain reaction threshold cycles for evaluating cow survival after coliform mastitis. Peer-reviewed conference abstract presented at the 33rd World Buiatrics Congress, Istanbul, Turkey, 6-10 September 2026, pp. 604–605.
The aim of this epidemiologic research was to identify optimal drying-off practices to maintain good udder health and productivity while implementing prudent use of antibiotics. Cows are susceptible to mastitis particularly during the dry period and this underlines antibiotic dry cow therapy (DCT) as an important part of mastitis control. No previous research existed 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 utilized 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 was a clinical field trial, which contributed to finding criteria for identifying cows that need and benefit from dry cow treatments.
The project ran from 2018 to 2022 and was led by Prof. Päivi Rajala-Schultz. It was funded by the Finnish Ministry of Agriculture, the Finnish Veterinary Foundation, Valio Ltd, Vetcare Ltd, and Orion Pharma. Riitta Niemi, DVM, PhD, conducted her doctoral research as part of the project.
Vilar, M. J., M. Hovinen, H. Simojoki, and P. J. Rajala-Schultz. 2018. Short communication:
Vilar, M. J. and P. J. Rajala-Schultz. 2020.
Niemi, R. E., M. J. Vilar, I. R. Dohoo, M. Hovinen, H. Simojoki, and P. J. Rajala-Schultz. 2020.
Niemi, R. E., M. Hovinen, M. J. Vilar, H. Simojoki, and P. J. Rajala-Schultz. 2021.
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. 2022.
Heikkilä. A.-M., Niemi R.E., Hovinen M., Rajala-Schultz P.J. 2022.
Niemi R.E., Hovinen M., Rajala-Schultz P.J. 2024. Selective dry cow therapy: Clinical field trial on prevention and cure of intramammary infections, J. Dairy Sci.
Under the coordination of Riitta Niemi (University of Helsinki),
The current network builds upon earlier NKJ-supported networks —“Healthy udders for sustainable milk production” (2017–2019) and “Healthy udders with low or no use of antibiotics” (2020–2021)—which formed the basis for collaboration and knowledge exchange. The NKJ funding of these previous networks has been a crucial element to initiate and establish collaborations between the partners of the current network, to benefit from each other’s experiences, and to ensure a high scientific research quality. The established network assembles people with many different backgrounds in the context of udder health management who will bring up-to-date knowledge on evidence-based mastitis management from various successfully conducted and ongoing research projects, as well as from advisory work with farmers.
Network partners in Healthy udders through a herd health perspective
• University of Helsinki
• University of Life Sciences Norway
• Swedish University of Agricultural Sciences
• Swedish Veterinary Agency
• University of Copenhagen
Nordic Mastitis Research Seminar Series (2018–2026)
2018 – Uppsala, Sweden
2019 – Tuusula, Finland
2021 – Webinar (hosted from Oslo, Norway)
2022 – Copenhagen, Denmark (hybrid format)
2023 – Uppsala, Sweden
2024 – Ås, Norway
2025 - Tuusula, Finland
2026 - Copenhagen, Denmark
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.
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.