Meet the Members of the White Lab


Heather White, Ph. D.

Heather White did her undergraduate degree at Saint Mary’s College, Notre Dame, Indiana.  She then earned her Masters in (under the joint mentorship of Shawn Donkin and Mickey Latour) and her Ph.D. (under the mentorship of Shawn Donkin) in Nutritional Physiology at Purdue University.  SMC


After an NIH Postdoctoral Fellowship at the Indiana University School of Medicine, Heather joined the faculty in the Department of Animal Science at University of Connecticut.  She joined the Department of Dairy Science at the University of Wisconsin-Madison in April, 2013 and since then has taught a variety of classes including the graduate level Ruminant Nutritional Physiology I and II, as well as undergraduate level Comparative Animal Nutrition.

Heather enjoys gardening, knitting, and spending time with her family!

Sandy Bertics

Nutrition Group Lab Manager

Sandy is the lab manager for the Nutrition Research Group in the Department of Dairy Science.  Sandy oversees all lab activities, animal trials, grants, and trains graduate and undergraduate students.


White Lab Current Members: 

Sophia Erb

Research Specialist


The focus of my research is on understanding the regulation of lipolysis during periods of adipose tissue mobilization, specifically during the transition to lactation period. Much of my work is laboratory based, where Western Blotting and RT-qPCR are utilized to elucidate what is happening in the cows at the molecular level. I also participate in ongoing whole-animal and cell culture studies, as well as training or assisting new and current students at the graduate and undergraduate levels with lab procedures.


Henry Holdorf

Ph.D. Candidate

Stress reduces how efficiently nutrients are used for growth and production in dairy calves and lactating cows. Early growth and weaning in calves, the transition to lactation period in cows, and excessively hot and/or humid weather are all examples of stressful situations in dairy systems. These have been characterized by an increased risk of inflammation potentially related to compromised gastrointestinal barrier function, also referred to as “leaky” gut. Therefore, the objectives of my research are to characterize potential gastrointestinal barrier dysfunction during these stressful situations in dairy production systems and impacts on growth, milk production, and animal health. Additionally, I am interrogating the potential effects of nutritional interventions on reducing the risk of “leaky” gut, and inflammation to improve growth, and production.

In addition to my research, I am part of the graduate fellowship program with Purina Animal Nutrition, with intentions of becoming a dairy nutrition consultant. Being involved in research, and a doctoral program has broadened my technical knowledge, and critical thinking skills. The knowledge and skills I have gained are rooted in science with an eye on application in the field.


Malia Martin

Ph.D. Student co-advised by Dr. Heather White and Dr. Kent Weigel

My research is focused on residual feed intake and predicting feed intake. The first objective of my research is to identify physiological sources of variation of feed efficiency. By analyzing arterial-venous differences of circulating energy metabolites, we aim to identify differences in post absorptive metabolism and efficiency of use by the mammary gland. My second objective is to predict feed intake using feeding behavior data using an ear tag sensor in addition to milk spectra data. I received my Bachelor’s at the University of Minnesota Crookston in 2018.


Faith Baier, MS

Ph.D. student co-advised by Dr. Jennifer Van Os, Dr. Heather White, and Dr. Kent Weigel

My research is focused on social competition and feeding behavior in lactating dairy cows. The main objective of my research is to determine a novel, robust method of evaluating social dynamics in dairy cows. Ultimately, we aim to understand the relationship between social dynamics and feed efficiency to improve genomic selection and optimize dairy management practices.

I received my B.S. from the University of Wisconsin-River Falls and my M.S. from Colorado State University under Dr. Temple Grandin. Aside from graduate school, I enjoy spending time outdoors with my dog as well as with my family and friends.


Kathryn Ritz, MS

PhD Student

During my undergraduate career at UW-Madison, I had the opportunity to work in the Dairy Nutrition Lab with Dr. Dave Combs, which got me interested in forage quality and nutrition research. After graduating with my B.S. in Animal Science, I attended the University of Minnesota to research pasture forage quality and grazing dairy cattle in an organic dairy system with Dr. Brad Heins. After graduating with my M.S. in Animal Science, I worked as a Research Associate at Zinpro Corporation, where I worked on researching new products to improve animal health and production. I am excited to be back at UW Madison to pursue my PhD with Dr. Heather White for a future career in research or technical service in the dairy industry.

For my PhD research, I will be focusing on transition cow health, specifically hepatic nutrient partitioning and metabolism. I hope to learn more about risk factors and biomarkers to monitor transition cow health and to find strategies to improve dairy cow health during the transition period.

In my free time I enjoy reading, hiking with my dog, and playing trumpet in community band.


Billy Brown, PhD

Post-Doctoral Research Fellow

Billy is a Post-Doctoral Research Associate in the White Lab, having previously completed degrees at Kansas State University (BS ’10; PhD ‘20) and Michigan State University (MS ‘12).  His work has focused on metabolic and inflammatory mechanisms of feed intake regulation in peripartum dairy cows.  He has also conducted research on the use of novel feed byproducts in lactating dairy diets, forage processing methods, and silage hygiene.  Prior to returning to academia to work on his PhD, Billy spent 5 years in business development at the Kansas Department of Agriculture where his efforts focused on growing the state’s dairy industry, expanding markets for Kansas beef genetics in Latin America, and providing general agribusiness development support to Kansas companies.

In his spare time, Billy enjoys competing for best yard on the block (still trying to convince the neighbors to start a traveling trophy), gardening, leather-working, kayaking, running, competing in triathlons, judging dairy cattle shows, and cheering for the KSU Wildcats.  He and his wife, Jordan, look forward to exploring the Badger State.  As dairy enthusiasts, they plan on boosting the state’s cheese and ice cream industries – recommendations are welcome.

White Lab Alumni

Ryan Pralle, PhD A Wisconsin native, Dr. Pralle’s multidisciplinary Ph.D. research interrogated the pathology of lipid-related metabolic disorders (fatty liver and ketosis) in dairy cows and leveraged farm data streams to develop prediction tools for ketosis management. Dr. Pralle will be continuing his career in academia as an Assistant Professor at the University of Wisconsin-Platteville with a split appointment between research and teaching. His current research emphases are precision nutrition and metabolic health management. 

Rafael Oliveira, PhD Rafael Oliveira did his undergraduate and Masters at Federal University of Lavras, Brazil and obtained his DVM. His thesis entitled “Supplementation of late gestation dairy cows with beta-carotene”, under the mentorship of Marcos N. Pereira, was concluded in August 2014. From August 2014 to February 2015 he interned at Heather’s lab where he had the opportunity of participate in the research projects entitled “The Role Of Hepatic Adiponutrin In Regulating Lipid Accumulation In Dairy Cows” and “Improving detection and treatment of sub-clinical ketosis in dairy cows”. Dr. Oliveira will be working with Adisseo as a Technical Service Manager for the Upper Midwest, Northeast, and South territories.

Claira Seely, MS The objective of Claira’s research was to identify the relationship between liver triglyceride accumulation and circulating biomarkers related to energy balance, liver health, and inflammation during the transition to lactation period. An additional aim of her Master’s research was to create models that will allow for the prediction of liver triglyceride content at various points during the transition period from analyzed blood metabolites and milk production data. She will be continuing her studies at Cornell University with Dr. Jessica McArt.

Kristina Weld, PhD The goal of Dr. Weld’s research was to determine how different fatty acids may affect liver metabolism in transition cows. Examining the impact of different fatty acids  on liver health and metabolism, as well as milk production helped elucidate diet formulations and proactive measures Dr. Weld can take on farm to keep transition dairy cows healthy. Not only did Dr. Weld complete her Ph.D., but she also received her Master’s degree at UW-Madison under Dr. Lou Armentano and received her Bachelor’s from Mount Holyoke College in Massachusetts. She is now a consultant for Purina in the Southwestern part of Wisconsin.

Tawny Chandler, PhD For her Ph.D. program, Dr. Chandler focused on metabolic flux with the treatments of methionine and choline using a cell culture model to mimic the transition period in vivo. Measuring a variety of metabolites from glucose to BHB, to glycogen to TG, she was able to elucidate through the help of a tracing radioisotope how hepatocytes metabolize fatty acids and the effect methionine and/or choline had in this process.

Dr. Chandler is doing her post-doc with Dr. Sabine Mann at Cornell University.

Qian Zhang, PhD Dr. Zhang worked with choline and methionine in Dr. White’s lab, and now works at Adisseo as a technical consultant.

Valentina Caprarulo, PhD Dr. Caprarulo‘s PhD research activity was focused on animal nutrition aimed to investigate different aspects of animal nutrition and feed technology. She is currently doing her post-doc in Spain.

Frankie Tiberio, MS For her masters research, Frankie conducted a trial at UW’s Arlington Research Farm to determine the relationship between body condition score and onset of ketosis, and if residual feed intake (RFI) is correlated with incidence of ketosis. Her master’s degree was unique in that she participated as Vita Plus’s fellowship student. As a fellowship student, Frankie worked part-time for Vita Plus while completing her degree. She is now a full time consultant at Vita Plus.