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Katharine Knowlton

The Colonel Horace E. Alphin Professor of Dairy Science
Professional photo of Dr. Katharine Knowlton
Department of Dairy Science
2440 Litton-Reaves Hall
175 West Campus Drive
Blacksburg, VA 24061

Dr. Katharine Knowlton grew up on a dairy farm in Connecticut and earned her B. S. in Animal Science at Cornell University, her M.S. at Michigan State and her Ph.D. at the University of Maryland. Dr. Knowlton is a Professor in the Department of Dairy Science at Virginia Tech with a research and teaching program focused on environmental issues affecting the dairy industry. Dr. Knowlton is assistant coach of the Virginia Tech dairy judging team (national champions in 2006, 2008, 2009 and 2013!!), judges dairy shows across the US, and owns a small herd of Jersey cows. She is Principal Investigator or co-PI on $11.2 million in externally funded grants, and has authored 67 peer-reviewed papers.

Courses taught: Animal Agriculture and the Environment (DASC/APSC 3134); Dairy Cattle Evaluation (DASC 2484); Dairy Handling 101; Dairy Science First Year Experience


Lead undergraduate advisor and Curriculum Coordinator


Coach of the Virginia Tech Dairy Judging Team
(National champions 2006, 2008, 2009 and 2013)

Excretion and environmental fate of antibiotics and antibiotic resistant genes by livestock

Phosphorus intake and excretion in lactating cows

Grants Funded

Dr. Knowlton is Principal or Co-Principal Investigator on $11.2 million in externally funded grants for research on environmental issues pertaining to animal agriculture. Funding agencies include USDA, NSF, industry groups, and conservation organizations.


Ongoing Projects

Reducing Antibiotic Resistance from Farm to Fork

Public attitudes regarding the therapeutic use of antibiotics in the dairy industry

Publication access links

Peer reviewed materials at PubMed

Virginia Cooperative Extension Publications


Book Chapters

Knowlton, K. F. and P. P. Ray. 2014. Water-related issues in sustainability: Nitrogen and phosphorus management. In E. Kebraib (Ed.) Sustainable Animal Agriculture. CAB International.


Ray, P. P., Z. Zhao and K. F. Knowlton. 2014. Emerging contaminants in livestock manure: Hormones, antibiotics, and antibiotic resistance genes. In E. Kebraib (Ed.) Sustainable Animal Agriculture. CAB International.


Knowlton, K. F., D. K. Beede and E. Kebreab. 2010. Phosphorus and Calcium Requirements of Ruminants. pp 112-132 In D. Vitti and E. Kebraib (Ed.) Phosphorus and Calcium Utilization and Requirements in Farm Animals. CAB International.


Z. Zhao, K. F. Knowlton and N. G. Love. 2008. Hormones in Waste from Concentrated Animal Feeding Operations. pp 292-329 In D. Aga (Ed.), Fate of Pharmaceuticals in the Environment and in Water Treatment Systems. CRC Press, Taylor and Francis Books.


Refereed Book Reviews

Knowlton, K. F. 2004. Review of "Minerals in Animal and Human Nutrition, 2nd edition". Poultry Sci. 83: 132.

Increase understanding of the interaction of animal agriculture and the environment

Effect of nutrition on nutrient excretion by dairy cows, and potential impact on water quality

International Visiting Research Scholar, Peter Wall Institute for Advanced Studies, 
University of British Columbia

Dedicatee, the Milky Way (annual publication of the Dairy Club at Virginia Tech)

American Dairy Science Association (ADSA) , Cargill Young Scientist Award

Certificate of Teaching Excellence, Virginia Tech, College of Agriculture and Life Sciences

ADSA Foundation Scholar Lecture Award in Dairy Production

Epsilon Sigma Phi National Honorary Extension Fraternity,  State Team Award

ADSA Graduate Student Paper Competition winner

Purina Mills Graduate Research Fellowship

University of MD College of Agriculture, Richard F. Davis Memorial Scholarship

National Science Foundation Graduate Research Fellowship

American Feed Industry Association Graduate Scholarship

American Jersey Cattle Association/Bansen Scholarship

Purina Mills Graduate Research Fellowship (declined for NSF fellowship)

Professor,  Department of Dairy Science, Virginia Tech

Associate Professor,  Department of Dairy Science, Virginia Tech


Assistant Professor,  Department of Dairy Science, Virginia Tech


Research Scientist. Department of Dairy Science, Virginia Tech

Graduate Research Assistant, Department of Animal and Avian Sciences, 
University of Maryland

Graduate Research Assistant, Department of Animal Science, Michigan State University

Undergraduate Research Assistant, Department of Agricultural and Biological Engineering, Cornell University

1984-1987    Farm Manager,  Mixed livestock and dairy farm, Portland, Connecticutt

PhD    1997     University of Maryland & USDA-ARS Beltsville: Dairy Nutrition

MS       1993     Michigan State University: Dairy Nutrition

BS        1991     Cornell University: Animal Science

Visit YouTube Channel:  Virginia Tech Dairy Cattle Judging for more judging videos!

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Dairy Judging 101: Judging heifers, Part 3 (size)  (Above)

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Dairy Judging 101 Practice classes: Brown Swiss 4 year olds  (Above)


Visit YouTube Channel: Talking Cows with KFK and Uncle Al to see the latest episodes of cow talk!

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