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 University of Helsinki, Department of Production Animal Medicine and Finnish Food Authority. Prof Päivi Rajala-Schultz is the project leader and DVM, PhD Riitta Niemi the principal investigator. Tiina Autio, DVM, PhD from the Finnish Food Authority is a member of the research team and DVM Muusa Takala is conducting her doctoral research in the project.
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 research, lead by Prof Päivi Rajala-Schultz, was funded by the Finnish Ministry of Agriculture (568/03.01.02/2017), the Finnish Veterinary Foundation, Valio Ltd, Vetcare Ltd, and Orion Pharma. DVM Riitta Niemi conducted her doctoral research in the project.
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.
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.
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.
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., 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. https://doi.org/10.3168/jds.2021-20918
Niemi, R. 2022. Epidemiologic approach to antibiotic dry cow therapy in dairy herds. Doctoral dissertation
Heikkilä. A.-M., Niemi R.E., Hovinen M., Rajala-Schultz P.J. 2022. Economic perspectives on blanket and selective dry cow therapy. Agric. Food Sci, vol. 31, no. 4, pp. 297-306.
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. https://doi.org/10.3168/jds.2024-25287
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 Nordic mastitis researchers gathered for fifth seminar in Uppsala, Sweden, in September 2023. The sixth seminar was in Ås, Norway in September 2024.
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.