Dairy Digressions

What has the dairy science community learned since the March 2024 highly pathogenic avian influenza (HPAI) H5N1 outbreak in US dairy herds? That’s the question host Matt Lucy, PhD, is posing to two special guests on the pod: Nicole Martin, PhD, assistant research professor in dairy foods microbiology and associate director of the Milk Quality Improvement Program in the Department of Food Science at Cornell University, and Zelmar Rodriguez, DVM, PhD, assistant professor in the College of Veterinary Medicine at Michigan State University. The two experts are authors in the newly released hot topic special issue of JDS Communications dedicated to the H5N1 strain of avian influenza in dairy. Zelmar takes listeners through the epidemiology and clinical signs of the disease, recovery time for animals, and where we’re at with vaccine development and management now and into the future. Nicole walks us through her work on how HPAI H5N1 is impacting dairy foods, from what we know about viral loads in raw milk to the details on how fluid milk and dairy products are regulated and made safe through the 100-year-old Pasteurized Milk Ordinance. Ultimately, she explains, pasteurization is effective at eliminating H5N1 and reducing risk for consumers. Finally, the trio discusses where we are now in this outbreak and the remaining science still to be done—emphasizing the importance of connection, communication, and the strength of the dairy science community in getting us to this point.

Do you have unanswered H5N1 questions? Join us for a free one-hour Q&A with the authors of the JDS Communications special issue on October 16!

Connect with the Guests

Learn more about Nicole Martin, and connect with her on LinkedIn and Twitter/X.

Learn more about Zelmar Rodriguez, and connect with him on LinkedIn and Twitter/X.

Review the H5N1 updates from the US Department of Agriculture, US Centers for Disease Control and Prevention, and US Food and Drug Administration.  

Save the date for the 2025 ADSA Annual Meeting (June 22–25) in Louisville, Kentucky, and submit your abstracts before February 12!

Hot topic: Avian influenza subtype H5N1 in US dairy—A preliminary dairy foods perspective, JDS Communications (2024)

Hot topic: Epidemiological and clinical aspects of highly pathogenic avian influenza H5N1 in dairy cattle, JDS Communications (2024)

We’re celebrating dairy cow behavior this month on the pod as the special issue of JDS Communications, Behavior in Dairy Animals, launches! Host Matt Lucy chats with Katy Proudfoot, PhD, associate professor at the University of Prince Edward Island and director of the Sir James Dunn Animal Welfare Centre at the Atlantic Veterinary College in Prince Edward Island, and Emma Ternman, PhD, associate professor at Nord University. The two are coauthors of an Editor’s Choice article in the special issue devoted to estimating sleep in dairy cattle. Katy and Emma explain how both of their academic paths were filled with “banana peels” and lots of googling—all of which eventually led them to the study of behavior and welfare in dairy cows. They dive into their work to better measure sleep and rest in dairy cows, explaining that sleep serves several essential functions throughout the animal kingdom, so understanding sleep in dairy cows could help us to improve their overall welfare, health, and production. They review how scientists are currently measuring and estimating sleep in dairy cattle—from changes in behavior to electrodes placed on a cow’s head—including the limitations of these methods and where the science might go. As prey animals, dairy cows must be vigilant during the day and average only about three hours of total sleep time. But they can supplement this with “drowsing,” an intermediate state between waking and sleeping that allows cows to stay alert and continue ruminating while getting essential rest. The two explain, however, that this research is still in its infancy and much work still needs to be done to understand sleep in dairy herds—from how the lights and noise of a barn might impact cows to whether they dream. Finally, the guests give their best advice, including why sleep is just as important for dairy scientists as it is for cows, why no one should ever pull all-nighters, and how to make writing papers fun.

Episode Eighteen Show Notes

Learn more about Katy Proudfoot and connect with her on LinkedIn.

Learn more about Emma Ternman and connect with her on LinkedIn.

Want to learn more about the latest science of dairy cow

Catch up on the papers and the news articles discussed in the episode:

Methods used for estimating sleep in dairy cattle, JDS Communications (2024)

Effects of acute lying and sleep deprivation on metabolic and inflammatory responses of lactating dairy cows, Journal of Dairy Science (2021)

Sleep in dairy cows recorded with a non-invasive EEG technique, Applied Animal Behaviour Science (2012)

Buckle up for a lively episode, as we welcome the infectiously energetic Julio Giordano, DVM, PhD, professor of dairy cattle biology and management in the Department of Animal Science and a codirector of the Cornell Institute for Digital Agriculture at Cornell University. Julio originally hails from Balnearia, Argentina, where he grew up learning from his father’s practice as a dairy veterinarian and working on his family’s dairy farms. He joins Matt to explain how this early interest in dairy cow health led to a passion for the study of reproduction and a career in the United States. He takes listeners into the evolution of his work—from his most hated experiment as a PhD student to his current research, which involves pushing the bounds of digital agriculture innovation to benefit farms and their herds. In his lab today, he and his team are focused on integrating new technology with farming best practices to develop approachable tools and techniques to help farms maximize their herds’ health, productivity, and profitability—all while increasing sustainability. Julio also shares his best advice for which skills students should be building for a career in dairy science and why he chose a faculty position over a career in industry. The two friends also discuss if the traditional lecture format needs an overhaul for the next generation, the importance of family—hola a Soledad, Julito, and Benji—and how relationships with colleagues, mentors, and students make a career in dairy so rewarding.

Episode Seventeen Show Notes

Learn more about Julio Giordano and connect with him on LinkedIn and follow his lab on X/Twitter.

Are you interested in participating in future Discover Conference meetings? Save the date for the 47th Discover Conference happening May 5 to 8, 2025, in Itasca, Illinois.

Catch up on the papers and the news articles discussed in the episode:

Combining reproductive outcomes predictors and automated estrus alerts recorded during the voluntary waiting period identified subgroups of cows with different reproductive performance potential, Journal of Dairy Science (2024)

Effect of targeted clinical examination based on alerts from automated health monitoring systems on herd health and performance of lactating dairy cows, Journal of Dairy Science (2023)

Effect of increasing GnRH and PGF2α dose during Double Ovsynch on ovulatory response, luteal regression, and fertility of lactating dairy cows, Theriogenology (2013)

Reproduction in the era of genomics and automation, Reproduction, Fertility and Development (2014)

Effect of increasing GnRH and PGF2α dose during Double-Ovsynch on ovulatory response, luteal regression, and fertility of lactating dairy cows, Theriogenology (2013)

Changes in serum pregnancy-associated glycoprotein, pregnancy-specific protein B, and progesterone concentrations before and after induction of pregnancy loss in lactating dairy cows, Journal of Dairy Science (2012)

Possible strategies to increase ovulatory follicle size and reduce time to ovulation in lactating dairy cows, University of Tennessee dissertation (2007)

Catch an abbreviation you’re not sure about? Here is a

·        CIDR: controlled internal drug release

·        ELISA: enzyme-linked immunosorbent assay

·        FSH: follicle-stimulating hormone

·        GnRH: gonadotropin-releasing

·        hCG: human chorionic gonadotropin

·        LH: luteinizing hormone

·        PAG: pregnancy-associated glycoprotein

Have questions about how the recent H5N1 strain of avian influenza—or bird flu—outbreak is impacting cow health, worker safety, dairy products, and consumer trust?

This special bonus episode of Dairy Digressions takes you straight to the heart of the 2024 ADSA Annual Meeting, where top animal health and food safety experts tackle your most pressing H5N1 concerns. Join moderator Jessica McArt, PhD, DVM, DABVP (Dairy Practice), as she poses audience questions to panelists Pamela Ruegg, DVM, MPVM, David J. Ellis chair in antimicrobial resistance and director of the Antimicrobial Stewardship and Dairy Health Management Laboratory at Michigan State University, and Nicole Martin, PhD, assistant research professor in dairy foods microbiology and associate director of the Milk Quality Improvement Program in the Department of Food Science at Cornell University.

This episode is essential listening for anyone in the dairy sector!

Do you have unanswered H5N1 questions you’d like us to tackle on the pod? Send them to [email protected]! We’ll be back soon with more as the science around this outbreak develops.

Bonus Episode Show Notes

Connect with the Panel Participants

Learn more about Jess McArt’s work, and connect with her on LinkedIn, Twitter/X, and Instagram.  

Learn more about Pamela Ruegg, and connect with her on LinkedIn, Twitter/X, and YouTube.

Learn more about Nicole Martin, and connect with her on LinkedIn and Twitter/X.

Review the H5N1 responses from the US Department of Agriculture, US Centers for Disease Control and Prevention, and US Food and Drug Administration.  

Save the date for the 2025 ADSA Annual Meeting (June 22–25) in Louisville, Kentucky.

Catch Up on the Reports and Resources Discussed in the Episode

Persistence of influenza H5N1 and H1N1 viruses in unpasteurized milk on milking unit surfaces, Emerging Infectious Diseases (2024)

A One Health investigation into H5N1 avian influenza virus epizootics on two dairy farms, medRxiv preprint (2024)

Spillover of highly pathogenic avian influenza H5N1 virus to dairy cattle, Nature (2024)

Experimental reproduction of viral replication and disease in dairy calves and lactating cows inoculated with highly pathogenic avian influenza H5N1 clade 2.3.4.4b, bioRxiv preprint (2024)

Pathogenicity and transmissibility of bovine H5N1 influenza virus, Nature (2024)

2024 highly pathogenic avian influenza (H5N1): Michigan dairy herd and poultry flock summary, US Department of Agriculture (2024)

Highly pathogenic avian influenza A(H5N1) virus in animals: Interim recommendations for prevention, monitoring, and public health investigations, US Centers for Disease Control and Prevention (2024)

Highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus infection in domestic dairy cattle and cats, United States, 2024, Emerging Infectious Diseases (2024)

Fatal infection in ferrets after ocular inoculation with highly pathogenic avian influenza A(H5N1) virus, Emerging Infectious Diseases (2024)

Inactivation of highly pathogenic avian influenza virus with high temperature short time continuous flow pasteurization and virus detection in bulk milk tanks, Journal of Food Protection Preprint (2024)

Inactivation of avian influenza A(H5N1) virus in raw milk at 63°C and 72°C, New England Journal of Medicine (2024)

USDA announces $824 million in new funding to protect livestock health; launches voluntary H5N1 dairy herd status pilot program, US Department of Agriculture (2024)

Still reeling from the science outlined by Filippo Miglior, PhD, in episode 6 of the pod? Us too. That’s why we invited special guest Christine Baes, PhD, to give us a download on the follow-up project. Christine is a professor and department chair of the Department of Animal Biosciences and Research Chair in Livestock Genomics at the University of Guelph. She is interested in improving dairy cows’ health, welfare, and productivity through genetics and is the lead investigator of The Resilient Dairy Genome Project, a massive, international, collaborative research project aiming to develop genomic tools to breed more resilient dairy cows. Christine explains the project’s focus on interrelated activities—fertility, health (especially for calves), feed efficiency, and methane emissions—and how they can be translated and applied on farms to help them prepare for the future. Bringing together more than 30 co-investigators and 35 international partner organizations, this huge undertaking recognizes the complexity of dairy cows and the dairy sector. It takes an interdisciplinary approach, considering the ethical, environmental, economic, legal, and societal impacts. Matt and Christine also connect the dots between resilience and longevity, acknowledging the tension between maximizing genetic gains and ensuring cows have the long, healthy, and happy lives expected by customers and dairy professionals who cherish their animals. Christine also explains her journey from farm kid to geneticist and lets listeners peek behind the curtain of the decisions that go into updating the Lifetime Performance Index. Finally, the two farmers-at-heart bond

Episode Sixteen Show Notes

Learn more about Christine Baes’s work and connect with her on LinkedIn and Twitter/X. Explore The Resilient Dairy Genome Project and its precursor, The Efficient Dairy Genome Project.

Save the date for the next Discover Conference, happening May 5 to 8, 2025.

Start earning rewards and journal savings via the ADSA Loyalty Rewards Program for the Journal of Dairy Science and JDS Communications.

Catch up on the papers discussed in the episode:

The Resilient Dairy Genome Project—A general overview of methods and objectives related to feed efficiency and methane emissions, Journal of Dairy Science (2024)

Estimation of genetic parameters for feed efficiency traits using random regression models in dairy cattle, Journal of Dairy Science (2024)

Estimates of genetic parameters for rumination time, feed efficiency, and methane production traits in first lactation Holstein cows, Journal of Dairy Science (2024)

Predicting methane emission in Canadian Holstein dairy cattle using milk mid-infrared reflectance spectroscopy and other commonly available predictors via artificial neural networks, Journal of Dairy Science (2024)

Recording of calf diseases for potential use in breeding programs: a case study on calf respiratory illness and diarrhea, Canadian Journal of Dairy Science (2023)

Deep dive with us into the exciting world of stem cell research as we welcome Carl Jiang, PhD, associate professor at the University of Florida and member of the University of Florida Genetics Institute. Jiang’s work focuses on reproductive biology, with an emphasis on understanding the epigenetic mechanisms during the embryo-development period when most pregnancy losses occur. Carl and host Matt Lucy get caught up during the International Embryo Technology Society’s 50th Annual Conference and discuss Carl’s path from growing up in rural China to studying embryology after being encouraged by an undergraduate mentor. The two explain the importance of bovine pregnancy success and how our understanding of the mechanisms of blastocysts—the embryo’s early stage—has been hampered by a limited supply of embryos. In a remarkable breakthrough, however, Carl and his team developed an efficient method to assemble bovine blastoids—bovine blastocyst–like structures—via trophoblast stem cells. Although still in the early stages, this technology opens up a more accessible in vitro model for studying embryo development and helping to potentially reduce pregnancy loss and improve reproductive efficiency in tomorrow’s dairy herds. Carl also lets us behind the scenes of his lab, explaining why one-on-one mentorship and a diversity of voices from around the globe are so important to research success. Finally, he explains why “Journal Club Day” is his favorite day at work and how it can kickstart new ideas and a renewed passion for science.

Episode Fifteen Show Notes

Learn more about Carl Jiang’s work and connect with him on LinkedIn and Twitter/X.

Save the date for the 51st International Embryo Technology Society Annual Conference (January 18–21, 2025, in Fort Worth, TX).

Start earning rewards and journal savings via the ADSA Loyalty Rewards Program for the Journal of Dairy Science and JDS Communications.

Catch up on the papers discussed in the episode:

Establishment of bovine trophoblast stem cells, Cell Reports (2023)

Bovine blastocyst-like structures derived from stem cell cultures, Cell Stem Cell (2023)

We don’t pick favorites among our guests, but we’re especially thrilled to welcome Jessica A. A. McArt, DVM, PhD, DABVP (Dairy Practice), to the pod! Jess is the new Editor in Chief of JDS Communications and associate professor of ambulatory and production medicine at Cornell University’s College of Veterinary Medicine, where her McArt Dairy Cow Lab focuses on improving cowside detection and the prevention of periparturient disease. Matt and Jess discuss her journey into dairy science—from growing up in Alaska to helming JDS Communications to wrestling with the shocking fact that only 14% of scientific journal editors are women and only 8% are editors in chief. The two discuss the very real systemic gender inequality in academia, its effects on a career in dairy science, and the role these forces play in the current shortage of large-animal veterinary practitioners. Looking to the future, Jess outlines her vision for JDS Communications and her challenge for our community to question assumptions and welcome diverse voices. Taking listeners into her research, Jess explains her recent findings on early lactation disease markers, including hyperketonemia and hypocalcemia–plus an explanation of dyscalcemia, a new term in the scientific milieu that originated in her lab. Finally, Jess leaves us with the best advice she received as a young researcher and the reasons she advises her students and mentees to say “yes” to opportunities—even if it pushes them outside of their comfort zone.  

Join us for a special episode of Dairy Digressions recorded live at the International Embryo Technology Society’s 50th Annual Conference. Between sessions, host Matt Lucy sat down with Goetz Laible, PhD, biochemist and principal scientist at AgResearch and honorary associate professor at the University of Auckland in New Zealand. Their discussion walks listeners through Goetz’s work in developing and evaluating technologies for the genetic improvement of livestock. In the face of our warming climate, Goetz and his animal biotechnology team are working to advance gene-editing technology to help dairy herds cope better—and stay healthy and productive—with increasing heat exposure. The two also deep dive into the science behind Goetz’s recent work on light-colored coats in Holstein Friesian cows. Using direct editing of embryos, Goetz and his team amplified naturally occurring coat mutation—which makes some cows lighter than others—to create lighter-colored cows in a single generation. These animals still retain their classic spots but with increased white coverage and a dilution of black spots to a light gray. Lighter gene-edited cows absorb a staggering 40% less solar radiation than their dominantly black counterparts, representing an important step forward for grass-fed dairy herds that spend most of their time outdoors. Listen in as Goetz sheds light on the potential applications of this technology in dairy herds, including his experience taking it to producers. He and Matt discuss the changing tides when it comes to farmer and consumer openness toward biotechnologies with the potential to help cows lead healthier, happier lives. An avid traveler, Goetz also shares his favorite perk of working in science and his advice for young scientists to embrace collaboration.

Episode Thirteen Show Notes

Learn more about Goetz Laible’s work with AgResearch and connect with him on LinkedIn.

Save the date for the 51st International Embryo Technology Society Annual Conference (January 18–21, 2025, in Fort Worth, TX).

Catch up on the papers discussed in the episode:

Production of light-coloured, low heat-absorbing Holstein Friesian cattle by precise embryo-mediated genome editing, Reproduction, Fertility and Development (2023)

Cytoplasmic injection of zygotes to genome edit naturally occurring sequence variants into bovine embryos, Frontiers in Genetics (2022)

Embryo-mediated genome editing for accelerated genetic improvement of livestock, Frontiers of Agricultural Science and Engineering (2020)

Cattle with a precise, zygote-mediated deletion safely eliminate the major milk allergen beta-lactoglobulin, Scientific Reports (2018)

Targeted microRNA expression in dairy cattle directs production of β-lactoglobulin-free, high-casein milk, Proceedings of the National Academy of Sciences (2012)

Why does the dairy sector have such a good story to tell about environmental sustainability, and how can each of us be a better storyteller for the industry? Join us for a mega episode of Dairy Digressions to find out! Host Matt Lucy is joined by esteemed guest Frank Mitloehner, PhD, a professor and extension specialist in the Department of Animal Science at the University of California, Davis, and director of the UC Davis CLEAR Center. An agricultural engineer and air-quality expert, Frank explains exactly why today’s climate change is outside of normal climate patterns, outlines the three main gases responsible for the greenhouse gas effect (carbon dioxide, methane, and nitrous oxide), and illustrates how their increase leads to higher environmental temperatures. While we know that the energy sector, particularly carbon from fossil fuels, accounts for the majority of global emissions, agriculture and the methane from livestock play a critical role in moving the needle toward our shared net zero–emissions future. With a majority of American refrigerators containing animal-sourced foods, Frank is focused on how we can produce those foods while addressing environmental issues ranging from air quality and emissions to animal welfare, worker health and safety, and more. Using Frank’s home state of California as an example, the two discuss how agriculture is currently excelling in finding ways to turn methane from a liability into an asset; dairy farms are on track to achieve 40% or more methane reduction by 2030, reach climate neutrality, and sell credits to other sectors. Despite these incredible advancements, it can feel like the climate narrative around agriculture remains thorny. Frank explains why he established the CLEAR Center and his work—including a recent trip to speak at COP28—to not only advance the science around climate in agriculture but to break down misconceptions and help consumers and thought leaders better understand the importance of agriculture in sustainably nourishing the world.

Episode Twelve Show Notes

Learn more about Frank Mitloehner’s work at the UC Davis CLEAR Center, read his blog posts, and connect with him on LinkedIn and X/Twitter.

Catch up on the papers and the news articles discussed in the

Big oil distracts from their carbon footprint by tricking you to focus on yours, GHG Guru (2020)

New report: California is pioneering a pathway to significant dairy methane reduction, UC Davis CLEAR Center (2022)

Sixth Assessment Report (AR6), Intergovernmental Panel on Climate Change (2023)

Animal board invited review: Opportunities and challenges in using GWP* to report the impact of ruminant livestock on global temperature change, Animal (2023)

Fifty years of environmental progress for United States dairy farms, Journal of Dairy Science (2024)

We’re kicking off the new year—and our new season of Dairy Digressions—with a special guest, Pete Hansen, PhD, Distinguished Professor of Animal Sciences and L. E. “Red” Larson Professor at the University of Florida. Pete’s research focuses on embryo physiology and developing new management strategies for increasing dairy cattle fertility, particularly in the face of heat stress and a warming climate. A leader in embryology and early embryonic loss, Pete explains when embryos are most sensitive to heat stress and why—including the scientific tools we have for preventing these effects—from genetic selection to embryo transfer to management for cow health and the potential future of artificial embryos from stem cells. A longtime mentor to undergraduate and graduate students (don’t miss his paper on the topic!), Pete also lets listeners in on his teaching philosophy and shares tips for crafting a lab environment that fosters collaboration, hard work, and joy around science.

Episode Eleven Show Notes

Learn more about Pete Hansen’s work at the University of Florida, and connect with him on LinkedIn and X/Twitter.

Are you interested in learning more about the journal

Catch up on the papers and the news article discussed on the

Reflections on a career as a graduate mentor—from baby steps at Wisconsin to today, Journal

Stem cells used to model a two-week-old human embryo, Nature

Complete human day 14 post-implantation embryo models from naive ES cells, Nature

Pluripotent stem cell-derived model of the post-implantation