36th BRITISH MASTITIS CONFERENCE
The 36th British Mastitis Conference was held on 12 June 2024 at Sixways Stadium, Worcester, with the highest number of delegates for some years. This year’s pre-conference Workshop on 11 June focused on milk harvesting and milking time assessments together with Mastitis Control Plan case studies and data management. It was delivered by Ian Ohnstad and James Breen.
It would not be possible to hold the British Mastitis Conference without the continuing financial support of sponsors – Vetoquinol, Mastatest, ATL Agricultural Technology Ltd, DairySmart, DeLaval, Boehringer Ingelheim, Milkrite InterPulse, ADF Milking, Zoetis and Ambic Milking Equipment. Oxi-Tech Solutions Ltd sponsored the best poster competition as judged by the delegates, with the majority represented by veterinarians, farm consultants, pharma and chemical industries, research scientists, academics and an increasing number of students. This year the organising and scientific committee were able to bring together a mix of researchers and practitioners from the UK, Ireland and New Zealand, with posters representing collaborations between the UK, Ireland, Sweden, New Zealand and the USA.
The first presentation was by Eric Hillerton, former chairperson of BMC before his move to New Zealand in 2006 to take up the role of Chief Scientist at DairyNZ Ltd. Eric´s presentation was on a “Review of mastitis research and what does the future hold?”. He suggested that mastitis research had been fixated on what was beneficial to the cow, and some for the farmer. In a combined 75+ years of mastitis research he advised that we have gained personal experience or worked with others in virtually every aspect of research. It did not take us long to realise that decades of effort, then and now, have been dedicated to infection and disease and rarely had a main focus been on health. He then gave some thoughts on what may have worked, some on areas that have consumed time and resources way beyond any possible value, and some areas that were never going to provide anything of value to the cow. Eric´s review looked at International Dairy Federation (IDF) symposium in Reading (1975), Kiel (1985) and a review given at the 2011 NMC Annual Meeting. In essence, priorities identified over the decades still applied equally now. Eric questioned why so little had been achieved? But, also, why many topics had not been revised. He did, however, highlight some huge successes, based on research, where the adverse effects of the milking machine have largely disappeared, when it is managed well; the success of teat dipping (done properly) remains an absolute essential, (although questioning whether the newer dips themselves had delivered much better effects); culling continues to serve us well, mostly for Staph cows and that antibiotics have generally been beneficial (mostly in dry cows). However, he suggested that the evidence tells us is there is a continuing focus on dealing with the consequences of infection and disease, the things that have occurred when we have failed to maintain a healthy udder. This is the antithesis of the highly successful work of 60 years ago to prevent and eliminate infection. He then described various studies which he felt had not moved the udder health story along but finished the presentation with information on a series of trials and studies that suggest we may, at last, get real progress in using genetics to manage mammary gland health rather than focusing on mastitis treatments, leading to the aim of the “no mastitis herd”.
The following speaker was Tom Greenham, Advanced Milking, UK who gave a presentation on “Practical management of udder health in automated milking systems.” He advised that udder health management in automated milking systems (AMS) has many challenges in common with conventional milking herds (CMS), but also features numerous additional risk factors that are unique to automated systems. Risk factors for intramammary infection (IMI) that are unique to AMS have previously been comprehensively described by Tom at the 2020 BMC). Tom then expanded on the specific action points required to maintain good udder health with AMS, including in the areas of udder health monitoring including clinical and sub-clinical detection issues; practical approaches to udder health monitoring in AMS; manging environmental risk factors, specifically pre-milking teat hygiene and housing hygiene; managing contagious mastitis risk factors through surveillance, post-milking teat disinfection, robot hygiene and managing infected cows; and finally managing the cow factors for IMI risk such as teat health, cow mobility and trace element status. Tom finished by commenting that there are many monitoring and management practices that are common to both AMS and CMS herds. However, in both measuring udder health and minimising udder health risks, understanding these AMS requirements allows farmers and their advisors to optimise udder health and benchmark performance against other AMS and CMS herds.
Four KT posters were selected for oral presentation from the thirteen submitted.Al Manning, QMMS Ltd, UK presented information on the“Use of mastitis pattern analysis reports to monitor udder health on UK dairy farms”.Rosa Ana Puentes Garrido, University of Liverpool, UK described a study on “Exploring udder cleft dermatitis: cow specific contributors revealed!”.This was followed by Ben Davidson, DairySmart, New Zealand who presented data on a “Comparison of two selective dry cow therapy protocols”.The final Knowledge Transfer (KT) presentation was by Judith Roberts, Map of Ag, UK on “Trends in cattle intramammary tube usage over recent years in Great Britain”.Rosa Ana´s poster was voted the Best Poster of the 2024 BMC by the delegates.
After the lunch break Jonny Slack, Dolphenby Farm, Cumbria, UK explained his management methods in “Reducing somatic cell count in a spring calving herd.” He described how the farm reduced the average annual SCC in the spring block calving herd from 187,000 to 89,000, the issues they faced, and the data used to pinpoint the bottle necks and problems within their herd management system, together with the hands-on approach by the whole team to solve these, with consultancy provided by Ian Ohnstad. The herd comprises 500 cows calving between the start of February and end of April, with a stocking rate of 2.5 cows per hectare. The herd was initially brought together with heifers from seven farms and as expected the SCC increased as the animals matured. However, for a number of reasons Jonny explained that the herd in 2018 had a SCC of 300,000 with action having to be taken due to the loss of SCC bonus payments. Actions included teat sealing all heifers (after a small initial on-farm study gave the staff confidence in the concept), treatment of teat warts (time consuming but effective), improvement in teat condition by changes to the milking routine and use of a higher quality teat disinfectant, a change from quarterly to monthly milk recording, use of CMT on all freshly calved animals, zero tolerance to Staphylococcus aureus, changes to selective dry cow therapy and drying cows off and improved cubicle care. Jonny explained these actions, besides reducing the SCC also benefited clinical mastitis cases (now at 7 cases per 100 cows) and overall herd profitability with achieving the SCC bonus adding £15,000 to the business with the reduction in clinical cases adding a further £37,500 plus savings in dry cow therapy. Jonny concluded his presentation with the biggest gain being time saved due to improved udder health and improved staff morale.
David Gleeson, Teagasc, Ireland, discussed “Meeting the challenges of chlorine-free cleaning of milking equipment.” David advised that chlorate has emerged as a residue of concern in recent years due to its capacity to inhibit iodine metabolism in the thyroid gland. This inhibition is of particular importance to infants and young children whose thyroid gland is inherently underdeveloped. Therefore, chlorate is of particular concern in infant milk formula (IMF) manufacture. Chlorate is a product of chlorine degradation which occurs over time in sodium hypochlorite and chlorine dioxide, depending on storage conditions. As we know these products are commonly used in the cleaning and disinfection of both milking equipment and food processing plants. They may also be used for water disinfection, with this water being subsequently utilised by some dairy farms and milk processing sites. A further residue linked to chlorine use is Trichlormethane (TCM), which is relevant to the production of lactic butter in the Republic of Ireland (ROI). The importance of both IMF and lactic butter to export markets and the importance of minimising the risks that chlorine derived residues pose, has resulted in the use of chlorine for cleaning and disinfection purposes being prohibited on dairy farms in Ireland since January 1st 2021. He stated that effectively clean milking equipment using ‘chlorine-free’ cleaning protocols relied upon a number of factors. This followed a series of trials at Teagsasc, culminating in the recommendations for five wash protocols for use with milking machines with three for cleaning bulk milk tanks. These protocols involve a combination of alkali detergent washes (sodium hydroxide), acid descales (phosphoric/ nitric acid) and in some instances, the use of a sanitizer (peracetic acid). David described the various methods to be used, depending on size of milking parlour (number of milking units), pipelines and dump lines. He further explained the factors that can affect successful chlorine-free cleaning, including the importance of calibrating chemical dosing equipment, ensuring adequate volumes of wash and rinse solutions, frequency of acid de-scale washes and correct draining of milking equipment and bulk milk tanks. David concluded that the adoption of chlorine-free cleaning protocols on dairy farms in the ROI had resulted in a significant reduction in both the levels and occurrence of both chlorate and TCM residues in bulk tank milk. Some remaining residues detected on a minimal number of farm milks may be due to intermittent use of chlorine, misuse of chlorinated water and some teat disinfectant products.
The final paper of the 2024 British Mastitis Conference was the ever-popular presentation of a practical mastitis case study. James Breen, University of Nottingham, UK and Map of Ag, Cumbria, UK, introduced his farmer clients, Peter and Emma Charles, Mount Pleasant Farm, Kings Norton, UK, prior to reporting on the “Implementation of the AHDB Dairy Mastitis Control Plan: reducing environmental infections and clinical mastitis incidence rate.” James advised that the AHDB Dairy Mastitis Control Plan was implemented on the farm in the autumn of 2020 for an all year round calving dairy herd after a request for a second opinion for increased clinical mastitis incidence rate. Following analysis of individual cow somatic cell count data and clinical mastitis event data from the milk recording and on-farm database, the herd mastitis infection ‘pattern’ was judged to be predominantly one of environmental infections of apparent lactating period origin, with seasonal infection patterns associated with summer and Gram-negative infections confirmed on bacteriology. In discussions with Peter and Emma, together with the farm veterinary surgeon, a practical focus on lactating cow management was prioritised through 2021 and 2022, which included improvement of building ventilation, increased availability of loafing space, cubicle bed management and pre-milking teat disinfection routine. Whilst the herd average somatic cell count (SCC) remained similar (181,000 cells/ml for the 12 months ending autumn 2020 and 172,000 cells/ml for the 12 months ending autumn 2023), there has been a dramatic reduction in the incidence rate of clinical mastitis events. Between the end of 2019 and the end of 2023, the incidence rate of clinical mastitis decreased from 60 cases per 100 cows/year for the 12 months ending December 2019 (135 clinical mastitis events reported), to 25 cases per 100 cows/year for the 12 months ending December 2023 (57 clinical mastitis events reported), with no change in detection or reporting methodology. This has been driven by a reduction in the incidence rate of first cases of clinical mastitis, in particular the rate at which cows were detected and reported with a first case of clinical mastitis after the first 30 days of lactation, which reduced from 3 in 12 cows affected for the 12 months to the end of 2019 to 1.7 in 12 cows affected for the 12 months to the end of 2023 (target less than 2 in 12 cows affected). Comparing the 12 months ending December 2019 with the 12 months ending December 2023, the estimated recoverable cost from improved control of clinical mastitis in the herd is close to £20,000, or around 1 penny per litre. Finally, the reduction in herd mastitis control has played a part in the reduction in overall amount of mg of antibiotic used per Population Correction Unit (PCU), reduced from 20.7mg/PCU to 11 mg/PCU over a three year period, with similar reductions in the average Defined Daily Dose (DDD) of antibiotic (from 4 to 2.5 daily doses over the same period) and average Defined Course Dose (DCD) of antibiotic (from 1.55 to 1.03 courses over the same time period). James concluded that the implementation of a structured approach to mastitis control reduces new intra-mammary infections and clinical mastitis incidence rate and leads to a reduction in antibiotic use. Environmental mastitis infection patterns during lactation are common and often require a combination of management changes, including housing, space, ventilation, and bedding management as well as teat preparation.
The 2025 British Mastitis Conference will be held on Wednesday 18 June 2025, with the workshop on the previous day, covering the topics of the Cows´ environment together with case studies using the Mastitis Control Plan and data management. More information is available at www.britishmastitisconference.org.uk where all previous proceedings are available to download.
