One might easily say that California’s “bread and butter” is the dairy industry. Dairying is California’s number one agricultural commodity and California’s dairy farms produce 20 percent of the nation’s milk supply. Pretty impressive, since 99 percent of California’s dairy farms are owned and operated by individual families. These families have continued to become more efficient and effective at milk production as the demand for California’s milk products has grown over the years. Individual dairy operations, as well as the dairy industry, have invested in technology and training to support more complex and dynamic dairying management practices. Investment in cutting-edge cow health screening and tracking systems, as well as advanced training for veterinarians and herd management consultants, will continue to be paramount in assisting the evolving industry’s ability to continue to provide high-quality dairy products for our growing population.
Preparing Our Future Veterinarians for Modern Dairy Farming
One example of the industry’s investment is the Veterinary Medicine Teaching & Research Center (VMTRC) at UC Davis. Located in Tulare, the heart of dairy country, Dr. Terry Lehenbauer and his team at the VMTRC provide veterinarians-in-training the opportunity for hands-on experience and practical instruction. Access to teaching herds combined with VMTRC’s close ties with local commercial dairy farms enables these vets to practice treating and managing herds of dairy cows within the complex systems they will encounter in practice on dairy farms.
“The dairy industry is consolidating and one outcome is that dairy farms are becoming much more complicated in their management needs—and that includes veterinary care,” Lehenbauer explained. “Vets need specialized training to be able to address the variety of needs in these herds, including the prevention of disease, animal welfare and productivity—all the things a dairy cow needs to be a healthy, good dairy cow.”
One of the biggest changes is that dairy farms must manage their cows in groups, reserving individual care for when it is necessary. This higher-level management means setting up systems so that each individual in the group gets everything it needs. A large component of that system is preventative care, including vaccinations and efficient monitoring to catch any issues before they develop into serious concerns.
“Larger herds have a multiplier effect,” Lehenbauer added. “Whatever vets do gets multiplied by multiple animals.” The economic and welfare implications of this multiplier effect means that vets treating such herds must be efficient and accurate. A single mistake or delay in identifying an animal with an infectious disease could result in a costly outbreak involving several animals. Avoiding such mistakes requires advanced knowledge, training, and experience—and that is exactly what the VMTRC seeks to provide.
PCR a Better Diagnostic Tool for Detecting Mastitis
“Every vet student will work with cattle,” Lehenbauer said. “But the vet students at the VMTRC work on diagnostic skills and understanding treatment protocols on the same scale that happens in the real world—they get to work in the largest dairy county in the United States, giving them the vital skills to be the vets we need in the future.”
The VMTRC is not just a teaching school—it is also a research center, and the professors are all involved in projects to help improve the management and health of dairy cows. Drs. Maria Marco, Sharif Aly and Lehenbauer are leading the testing of new technologies to rapidly identify the disease-causing agents of mastitis—an important health concern in dairy cows. Working on a collaborative project funded by the California Dairy Research Foundation (CDRF) through dairy Checkoff Dollars, the project’s research teams bring together experience from the VMTRC and the UC Davis Food Science and Technology Department.
Mastitis is when the udder of a cow becomes inflamed, usually due to an infection, and is one of the most costly diseases in the dairy industry. Figuring out the cause of mastitis is often the most time-consuming step, and is crucial to prescribing the correct treatment. Delays in identifying the cause and starting treatment can result in worsening the infection or a spread of the infection through a herd. The project team are working on a technological development that will increase both the speed and accuracy of identification of infection.
One of the most important causes of a mastitis infection is a genus of microorganisms called Mycoplasma. These microorganisms are different than many other bacteria because they don’t have cell walls, the stiff outer shell that most bacteria possess; this makes growing mycoplasma in a lab difficult. It can take up to a week before a vet is able to determine if a milk sample contains mycoplasma. And even then, there is a common species of mycoplasma that doesn’t cause disease, yet looks just like its dangerous, disease-causing cousin.
That’s why testing this new molecular biology-based technology is a big step forward. The process uses a technology called real-time or quantitative polymerase chain reactions, or qPCR, to specifically identify and quantify bacterial DNA present in a milk sample. Imagine going from trying to identify a criminal by using a fuzzy security camera image of a getaway car to having a process that will quickly deliver the VIN number, license plate, registration, and owner of that car. This PCR test will be able to identify exactly what kind of bacteria are in a milk sample, as well as whether those bacteria are harmful or not.
The team is working to validate the technology and increase the speed and simplicity of this system for identification and quantification of bacteria in raw milk, dairy processing streams and dairy products.
“PCR can be a useful diagnostic method when combined with other currently available tools and herd data,” said Dr. Gonca Pasin, executive director of CDRF.
Pasin expects these PCR-based techniques to gain a more prominent place in mastitis diagnostics once the assay results have been developed and validated.
“PCR-based assays can be viewed as more expedient than some of the lengthy traditional culture-based methods,” Pasin said. “The more rapid availability of results could allow for quicker treatment of infections and refraining from administering treatment unnecessarily.”
The impact of this project will benefit the broader California dairy industry by improving overall dairy cattle health, increasing industry profits and ensuring consistently high-quality dairy products available to consumers.