The 33rd British Mastitis Conference was held on 10 November 2021, returning to its usual venue in Worcester following the virtual conference in 2020 due to the Covid 19 pandemic. The workshop on mastitis data management and control with emphasis on machine milking was presented by James Breen and Ian Ohnstad, on the previous day. Due to the continuing uncertainty regarding Covid, delegate numbers were lower than usual although feedback was extremely positive. BMC could not be held, as with most scientific conferences, without the continuing financial support of sponsors, with Vetoquinol and Fullwood Packo both offering Platinum sponsorship in 2021. Although the target audience is mainly veterinarians, farm consultants, research scientists, students and academics – it is aimed at anyone with an interest in dairy farming and mastitis. The organising and scientific committee bring together a mix of researchers and practitioners from both the UK and further afield, where possible, although this was restricted to the UK and Ireland for the 2021 conference speakers.
The first speaker was Chris Davison, University of Strathclyde, Glasgow, UK, who presented a “Review of diagnostic testing of mastitis”. Chris highlighted that mastitis has significant impacts on both the health of the animal, and the cost to the farm. Although farm management practices can have a significant impact on control and treatment of this disease, there is no perfect solution. He advised that with tight operating margins there comes increasing farm size without a matching increase in on-farm labour, resulting in an increase in the use of automation. Traditional methods, such as Somatic Cell Count, enzymatic analysis or electrical activity of milk (as in automatic milking systems), don’t scale well to these changes in farm practice. Therefore, no method is able to be considered a gold standard, either due to cost, sensitivity, ease of application or ability to detect sub-clinical mastitis. Chris then discussed the novel approaches to diagnostic testing, including Lateral Flow Tests (a major project study was nearing publication) plus using a combination of behaviour collar, electrical conductivity and milk constituents. He suggested that such a combination, although not targeting mastitis specifically, can work as an early warning system for the herdsperson. However, Chris concluded that the most suitable approach is multi-faceted but that it had its problems in that this relied on manufacturers equipment “talking” to each other. Or, to allow the export of data to researchers and engineers who could build systems that aggregate data from multiple platforms – allowing the herdsperson to check just one unified system.
The following speaker was Ian Glover, Quality Milk Management Services Ltd, Wells, UK who examined the question “To treat or not to treat”. Ian advised that in the UK, the mean incidence of clinical mastitis has been found to be between 47 and 65 cases/100 cows/year. Whilst prevention of intramammary infection (IMI) is key to reducing the impact of mastitis on dairy units, the rate of cure of existing clinical and subclinical infections also plays an important role in control of infection prevalence. In other words, within-herd prevalence of infection is dependent mainly on the ratio of the rate of new infections to the rate of cures. The potential for IMI to be transferred between cows in a contagious manner further enhances the importance of effective cure; the within-herd cost of clinical mastitis is heavily determined by rates of transmission and of bacteriological cure. Ian suggested that the probability of a cure of a case of clinical mastitis is associated with various cow, pathogen and treatment factors. With this in mind a study was instigated, the aim of which was to create a model, incorporating only cow characteristics readily available at the time of case detection, for predicting the probability of cure of a case of clinical mastitis during lactation. Using data available from previous research on 52 UK dairy farms, mixed-effects modelling was employed to create a predictive model. Initial validation of this model was then accomplished using cross-validation. Preliminary work suggests the model is highly predictive of cure probability, and has the potential for use in real-time for informing treatment decisions in cases of clinical mastitis, based on the concept of “treatment worthiness”.
Four KT posters were selected for oral presentation. Clare Clabby, Teagasc, Ireland presented a study on “The impact of using teat seal only at dry-off on SCC and infection levels in the following lactation on 5 Irish commercial herds.” Rachel Hayton, British Cattle Veterinary Association and Synergy Farm Health, UK discussed a new initiative of “Online training for advisers to support udder health improvement through the QuarterPro initiative”. Ginny Sherwin, University of Nottingham, UK highlighted the results of a study on “Survival of Streptococcus uberis on bedding substrates”. The final KT presentation was by Al Manning, Quality Milk Management Services Ltd, Wells, UK on a “Descriptive study of Bactoscan failures on UK dairy farms (2010-2020)”.
After the lunch break Rachel Risden, Greenhills Farming, Exeter, and St Boniface Vets, Crediton, UK presented a paper on “The challenge of setting up a small-scale Direct Supply Business”. Although a practicing veterinary surgeon Rachel explained that changes to the family farm businesses lead to her and her husband setting up a new dairy unit at their farm and, due to location, entering the direct-sales market for their milk. Rachael discussed the methodology of starting up such a business, the potential regulatory issues, the planning involved, the problems encountered in selling milk to the final consumer via a vending machine and, of course, the necessity to provide a hygienic and wholesome product. Although a very full plant cleaning protocol was instigated from the outset, problems with milk hygiene quality after a short period was eventually found to be due to rusty internal welds in part of the pasteurisation equipment, which when removed lead to zero coliform counts. Rachel advised since the issue had been resolved that milk hygiene and keeping quality had not been an issue – but underlined the importance of regular bacteriological testing of the end product. Other factors to be considered when starting a direct sales milk business is what type of pasteuriser to invest (low temperature, long time or high temperature, short time equipment), location and type of vending machine, regulations, time elements of running such a business, the importance of plant cleaning, milk compositional quality (too high a fat content can cause havoc with dispensing flow meters), potential changes to calving patterns to ensure continuity of milk supply and to engage with social media. As Rachel concluded all are necessary to be successful, but direct positive feedback from the customers makes it all worthwhile.
Chris Hudson, University of Nottingham, UK looked at “Managing outcomes: what does the data show?”. Chris advised that the big data revolution has pervaded all areas of society over the past decade, and udder health management has seen a revolution in the way that data is used to support decision making, mostly focused on herd-level decisions. This had come about due to better computerised recording systems, partly due to increasing herd size, and the increased awareness by the dairy industry of using data effectively. Chris suggested that udder health could make a reasonable claim to be the aspect of herd health which has shown the biggest progress in how data is used over recent years. It is now widely accepted that analysis of data is a vital first step in addressing mastitis control, whether in the context of routine monitoring or investigating a problem. The AHDB Dairy Mastitis Control Plan and the recent QuarterPRO initiative exemplify this concept, and has seen widespread adoption and huge reach within the UK industry since the original launch of the plan in 2009. His presentation then discussed some of the potential areas of future development in the role of data to measure and predict outcomes in udder health, both at herd level and at individual cow level. Chris concluded that udder health has seen a massive improvement in the extent to which data is used to support decision making over the past decade, especially in terms of herd level control. This trend is likely to continue, as tools to support this process become more sophisticated and more accessible. In addition, he suggested that there is also substantial scope to use data more effectively to support decisions at the individual cow level.
The final paper of the 2021 British Mastitis Conference was the now regular presentation of practical mastitis case studies. The paper was presented by Ellie Button, Howells Veterinary Services Ltd, Easingwold, UK who reported on “AHDB mastitis control plan case study: environmental lactation pattern in a robotic milking herd”. Ellie explained that the AHDB Mastitis Control Plan (MCP) was launched in 2009 after a randomised controlled trial demonstrating the many benefits of a systematic and holistic approach to udder health in dairy farms. The first three years involved training of Plan Deliverers throughout the UK and using their experiences and data to model future use and development of the MCP. In 2020, a simplified and shorter version of the MCP, named QuarterPRO, was made available, with the recognition that many farms may prefer a lighter touch surveillance-style program where there is no sudden or severe breakdown in udder health. The process adheres to the same principles of data analysis and working with clients to create an agreed farm management plan. Ellie then described an AHDB Mastitis Control Plan she set up on a 110 cow AMS milked dairy herd in October 2020 at the request of the client, due to penalties resulting from high bulk milk somatic cell count (BMSCC). At that time the BMSCC twelve-month average was 271,000 cells/ml. Analysis of the data using the Mastitis Pattern Analysis Tool indicated the predominant pattern was that of new infections arising during lactation. The farm management plan agreed with the client focussed on improvements to the lactating cow environment, especially frequency of bedding application and a high standard of slurry scraping; and also highlighted issues associated with mastitis identification and treatment. Ellie advised that after implementation of the plan, lactational udder health parameters improved dramatically over the next four months, at which point concentration was required on the dry period environment. Agreed goals included the management of the dry period environment to the same standard as for the lactating herd, especially bedding and slurry procedures. At the second review, dry period new infections were much improved. However, lactation new infections were starting to deteriorate. At the final twelve-month review, lactational and dry udder health had significantly deteriorated over the summer due to two important factors: increased numbers of cows calving in July and August; and an interruption in the supply of bedding material. The figures were still better than those of October 2020, however the client was well aware they had lost a lot of ground. The conclusion was that this confirmed the original farm management plan had been a success, not just a coincidence, and it motivated the staff to return to the previous improved standards of environmental hygiene management. Ellie concluded that the case study exemplified both the success that can be achieved by engaging with the AHDB MCP, and the challenges associated with maintaining high standards in one area of farm management, either when beginning to focus on other areas, or when dealing with short term system failures such as too many cows calving or material supply issues. It also illustrated the beneficial impact of the ambitious targets of some milk contracts, since the client involved would not deny that they were motivated to change solely by the need to retain their contract, but neither would they deny the obvious benefits to cattle health, welfare and productivity they have observed as a result of their farm management improvements.
The 2022 British Mastitis Conference will be held on Wednesday 9 November 2022, with a workshop on the previous day. More information is available at www.britishmastitisconference.org.uk where all previous proceedings are available to download.