Why change practices & what are the benefits?
Dairy farmers, herd veterinarians, dairy industry consultants, and extension agents are well-versed in blanket dry cow treatment, which has been the standard practice used to prevent mastitis on dairy farms across the U.S. since the 1960s. Let’s face it, changing farm practices takes time and effort--and blanket treatment is just more familiar. So why change practices? Only you can decide if there is enough benefit for your farm to transition to SDCT. But we see trends coming down the pike that make the transition worthwhile.
Buying all of that medicine is expensive! Transitioning to SDCT can reduce antibiotic use at dry off by 50-80+%, which reduces pharmaceutical and treatment costs, averaging a savings of $6-$20 per cow in antibiotic tube costs alone (Betchel, 2018), as well as reduced labor costs. See the SDCT Cost Calculator to assess how much you might save on your farm.
Some farmers fear losing premiums or being dropped by their milk processors if their somatic cell count climbs high, especially with unstable milk prices. But four randomized, controlled research trials across North America and one specific to New York have shown no negative effects on SCC, milk production, and/or other health outcomes by implementing this practice. And with changing consumer demand, demonstrating support for public health will serve the industry.
Among herds that have good health management practices in place, SDCT is proven safe and effective for herd health on well managed farms when protocols are followed and cows are enrolled systematically. Note that veterinary involvement and well-trained employees are essential for SDCT success (UMNdairy, 2020).
It may require some time to perfect SDCT protocols for your farm. Some farmers who transitioned to SDCT noted that labor and management issues arose because it required additional protocol development, accurate and timely herd records, specific dry-off protocols, well trained employees, and animal monitoring through the dry period and at freshening for new mastitis infections. Selecting low-risk cows based on herd records and SCC test results, and monitoring cows during the dry period are keys to success in transitioning. If problems arise, working with your herd veterinarian to assess your plans and make small adjustments is best. The benefits will be worth the effort in the long term!
Consumer demand is changing
The public health consensus is that the overuse of antibiotics to treat people or animals leads harmful bacteria to become "resistant" to the antibiotics. This makes antibiotics less effective in treating infections in humans and animals alike. According to the Center for Disease Control, antibiotic resistant infection is now a major and increasing risk to human health such that 35,000 people die every year in the U.S. because of antibiotic resistant infection.
Consumers and buyers are increasingly aware of the risks of antibiotic resistance, and are already showing interest in buying dairy and meat products from farms that advance antibiotic stewardship. In 2020, for example, four school districts in Tompkins County, New York prioritized bids from food suppliers that sourced their beef from farms that had adopted selective instead of blanket dry cow treatment. More, demand is growing for labels to be used on foods of animal origin (see this article, “Antimicrobial‐resistant bacterial infections from foods of animal origin: understanding and effectively communicating to consumers”).
Though dry cow therapy represents a fraction of the antibiotics used in livestock, a transition to SDCT among dairy farmers in New York and across the U.S. will make a meaningful impact in total antimicrobial use. Whether medicines are used to treat people or animals, using them conservatively and treating only those that need it can help prevent antimicrobial resistance and keep medicines effective. Now, thanks to a better understanding of cow health, including the factors that drive mastitis risk at dry-off, cows can also be treated selectively.
NY dairy farmers can lead the way in antimicrobial stewardship
Today, New York dairy farmers and veterinarians are providing national leadership in creating models for reducing on-farm antimicrobial use while maintaining animal health, addressing both public health concerns and changes in consumer demand. The principles used on New York dairy farms are applicable to other livestock settings---which reduce the infection rate through improved management, followed by identification and treatment of only high risk individual animals.
In addition, regulation may be coming. The Maryland State legislature recently passed legislation requiring SDCT instead of blanket treatment. Several States across the Northeast are considering similar policies--including in New York. In the words of one dairy farmer, “it’s time for New York dairy farmers to get ahead of the curve, and lead the nation.”
60% of antibiotic use on dairy farms is for mastitis (Nydam et al., 2019)
30% of mastitis antibiotic usage is for Dry Cow Therapy (Reugg, 2018)