The Miner Institute Farm Report has been around for 36 years now, so I decided to look back at the first ever one that was published. The Farm Report dates from January 1982 and talks about a wide range of things from rotating corn hybrids to sulfur for alfalfa. One article that caught my eye was titled, “Mastitis – The, Battle Goes On” The article was written by Dr. Harry Randy, the past Director of Research and President of Miner Institute from the 1980s until his untimely death in 1991. Dr. Randy was very involved with day-to-day management of the herd, and in the article he discussed the ongoing issue the herd faced with the presence of mastitis.
In Dr. Randy’s article he described that the staph species, Staph aureus, and strep species were the cause of the majority of mastitis cases in the herd. Just about everything had been tried to lower the frequency of mastitis including pre- and post-dipping cows (which had been done for some time by then) and installing automatic takeoffs to try and eliminate the human error. Decisions were made to cull cows that were identified as “chronic”; selected based on average production, history of clinical mastitis, DHI somatic cell count, and bacteria culture. With these changes, the farm still didn’t see much change in the number of mastitis cases. The next plan of action was to have the milkers go through eight hours of training on milking systems and mastitis. By the end of that year it was their goal to install a low line and new washing system. The costs of training and equipment were deemed worthy of the investment. The somatic cell count dropped from 250,000 to 150,000 and they were only treating 2-3 cows a month for mastitis, compared to the 28 cows that were reported at the end of August the previous year.
How far has the dairy industry come since the 1980’s in mastitis control? Since 1980 the number of recorded mastitis cases in herds decreased from 37% to 20%, a large drop. Research initially focused on identifying and characterizing the causes of most mastitis, and from there developed antibiotics to help treatment and control. Further down the road antibiotic therapy, post dipping of cows, clean equipment, automatic takeoffs, vacuum fluctuations, and monitoring teat health were all strategies for controlling the spread of bacteria. Control of environmental factors such as having a dry clipped udder, cleanliness of stalls, bedding sources, and ensuring that cows eat after milking to allow time for closure of the streak canal, are all areas where recommendations have been developed over the years. Selecting genetic traits such as udder height and teat conformation have also helped cut down on the incidence of mastitis. Culling cows that are considered to be chronic is still a common practice on many farms. Vaccinations for mastitis were at one point starting to develop with researchers primarily targeting Staphylococcus aureus. The vaccination, however, didn’t prove to be effective.
How have things changed at Miner Institute since Dr. Randy wrote that article in 1982? First of all, the herd size has nearly quadrupled. Our dairy staff has done a great job in keeping our somatic cell count relatively low, averaging 115,000 in 2017 with several months under 100,000. Generally our herd treats 8-10 cases of mastitis per month which is a similar rate to the Miner Institute herd in 1982. We still battle with most of the same organisms, however Klebsiella seems to be our new challenge. As Dr. Randy indicated in 1982, milker training seems to have been the best investment to keep somatic cell counts low and reduce mastitis cases. While writing this article for the Farm Report I couldn’t help but think how far we have come with detection, treatment, and lowering the incidence of mastitis. So what does the future hold for mastitis in dairy herds across the world? Is there a future without mastitis? Maybe someone will write a follow-up article 36 years from now….stay tuned in 2054!