Rumen Protozoa: Friends, Foes, or Both? Implications for Dairy Nutrition.

Tuesday, June 30 · 10:00 AM EST

Rumen protozoa play a central role in rumen function, influencing feed digestion, nutrient utilisation, microbial protein synthesis, and methane production. While their activities can contribute to improved fibre degradation and rumen stability, they may also reduce nitrogen-use efficiency and increase methane emissions. As interest grows in improving the productivity and sustainability of dairy systems, understanding the complex role of rumen protozoa has become increasingly important. This presentation will review the latest science on rumen protozoa, including the major protozoal groups, their functions within the rumen ecosystem, and the factors that influence their abundance and activity. It will also examine current approaches for quantifying their contribution to rumen metabolism and discuss recent advances in nutritional modelling that enable protozoa to be explicitly represented in feeding systems, providing new opportunities to improve diet formulation and predict animal performance and environmental outcomes. 

Dr Michael Dineen is a Senior Research Officer in animal nutrition and physiology at Teagasc Moorepark. He holds a BSc in Animal Science from University College Dublin and completed a MPhil at Teagasc Moorepark in collaboration with Queen’s University Belfast. He subsequently completed his PhD at Cornell University, New York, under the supervision of Professor Michael Van Amburgh. At Cornell, Dr Dineen’s doctoral research focused on characterising the nutrient supply from pasture-based diets and on the evaluation and further development of the Cornell Net Carbohydrate and Protein System model. His current research programme in Teagasc focuses on improving the productive efficiency of lactating dairy cows while minimising environmental impacts. In addition, Dr Dineen is responsible for the Animal and Grassland Laboratory at Teagasc Moorepark and oversees a Teagasc dairy farm experimental research station. He has extensive teaching experience at both national and international levels and holds adjunct academic appointments as Adjunct Senior Lecturer at University College Cork and Adjunct Associate Professor at University College Dublin.