Keynote speakers

Below you can find the keynote speakers for the 15th International Symposium on Digestive Physiology of Pigs.

Optimizing resource utilization for future feeds

Evaluation of agricultural resources for optimal upcycling in pigs.
Pedro Urriola, University of Minnesota

Upcycle food waste and agriculture by-products into high value pork requires adequate evaluation of these resources. There are multiple restrictions to optimal utilization of these by-products including low digestibility and variable nutrient content that is typically linked to high content of dietary fibre. Content and survival of pathogens in by-products is an emerging concern. Therefore, a holistic approach is required to develop technologies that integrate solutions to these issues. These include understanding the effect of fibre on gut morphology and function and the subsequent impact of fibre modification. The extent of digestibility has limited value in predicting the overall value of the feed ingredients because it ignores the kinetics of nutrient degradation and the impact of nutrients on other gut function such as coping with food allergens, prevention of infectious diseases, and signalling to other systems. Consequently, we have increased our understanding of the impact of dietary fibre on cell composition of gut tissues and differentiation coupled with Systems Biology tools such as chemometrics, metabolomics, microbiome, metagenome, and data integration. In addition, we want to improve the nutritional value of high fibre feed ingredients by ammonia fibre expansion and solid state fermentation, which can breakdown fibre and antinutritional factors. Lastly, agriculture by-products may contain residues of antimicrobials and pathogens. Therefore, we have also measured degradation kinetics of antibiotics and viruses in raw materials to understand the impact of these elements when using high fibre by-products to support One Health.

Dr. Pedro E. Urriola is Research Associate Professor at the Department of Animal Sciences of the University of Minnesota. He is original from Venezuela, where he studied the equivalent to Veterinary Medicine at the Universidad Central de Venezuela. He completed an MSc at the University of Minnesota, and a PhD in Swine Nutrition at the University of Illinois. He worked as a Research and Development Manager at Cargill Animal Nutrition in Elk River, Minnesota. Together with the integrated Animal Systems Biology team in Minnesota he focuses on nutritional evaluation of agro-industrial co-products using LC-MS metabolomics, microbiome analyses, and gut physiology. In addition to feed evaluation projects, he is involved in research on the management and control of infectious diseases feed-related transmission, such as African Swine Fever.

Dynamics of digestion and absorption

Carbohydrate Digestion: The importance of the proximal and distal stomach during digestion in growing pigs.
Gail Bornhorst, University of California, Davis

During the process of carbohydrate digestion, both physical and chemical breakdown contribute to the gastric emptying and glycaemic response of a meal. In studies using growing pigs, differences in pH, apparent enzyme activity, mixing, and physical breakdown have been observed between the proximal and distal stomach regions after carbohydrate-based meals of varying starch botanical origin and structure. Understanding the unique role of the proximal and distal stomach in meal breakdown is critical to tailor food product composition, structure, particle size, and processing for specific digestive outcomes.

Dr. Gail M. Bornhorst is an Associate Professor of Food Engineering in the Departments of Biological and Agricultural Engineering and Food Science and Technology at the University of California Davis. She received her B.S. degree from Michigan State University (2007) and her M.S. and Ph.D. from University of California Davis (M.S. 2010, Ph.D. 2012) in biological systems engineering. She joined the UC Davis faculty in 2014. Her research involves developing a quantitative understanding of food structural breakdown during digestion and the impact on nutrient release and food functional properties, development of dynamic in vitro model systems for studying digestion, and modeling of digestion processes. She is the author of 40 refereed papers. Dr. Bornhorst is the Chair-Elect in the Food Engineering Division of IFT, the Secretary of the Society of Food Engineering, and is serving as the past-chair of the NC1023 multi-state committee for Engineering for Food Safety and Quality.

Phytate degradation, P and Ca absorption and digestibility in pigs
Markus Rodehutscord, University of Hohenheim, Stuttgart

Phytate is the main source of P in diets for pigs. This presentation provides a summary of recent findings on the variability of phytate degradation and the occurrence of phytate degradation products in different sections of the digestive tract of pigs. It includes interactions with the supply of digestible P and digestible Ca, mechanisms of absorption and aspects of regulation. Effects of exogenous enzymes are considered. The presentation also includes similarities and differences between pigs and broiler chickens.

Prof. dr. Markus Rodehutscord is the professor of animal nutrition in the Institute of Animal Science at the University of Hohenheim, Germany. The research of his group is on amino acid and mineral metabolism of livestock and related aspects of feedstuff evaluation for different animal species. A current focus is on phytate degradation in the digestive tract. To date, Dr. Rodehutscord has completed supervision of 37 doctoral students, co-authored 250 peer-reviewed journal publications, and coordinates interdisciplinary research consortia. Dr. Rodehutscord serves as the chair of the Standing Committee on Nutrient Requirements of the Society of Nutritional Physiology, is involved in the editorial processes of scientific journals, and has been awarded prestigious prices.

Functionality of the intestinal microbiome

Quantitative microbiome profiling in health and disease.
Jeroen Raes, Katholic University Leuven

Alterations in the gut microbiota have been linked to various pathologies, ranging from inflammatory bowel disease and diabetes to cancer. Although large numbers of clinical studies aiming at microbiome-based disease markers are currently being performed, our basic knowledge about the normal variability of the human intestinal microbiota and its determining factors remains limited. Prof. Raes will discuss findings of a large-scale study of the gut microbiome variation in a geographically confined region, in which analysis of microbiome variability in health identified the primary parameters associated to microbiome composition. He will discuss experiences in large-scale microbiome monitoring, show how the development of dedicated computational approaches can assist in microbiome analysis and interpretation, and which confounders are essential for inclusion in microbiome disease research. In addition, Prof. Raes will show how Quantitative Microbiome Profiling, which combines microbiomics with flow cytometry-based cell counts, is profoundly changing views on gut microbiota variation and allows the identification of an inflammation-associated, cross-disease enterotype.

Prof. Jeroen Raes (m) is professor at KU Leuven since 2013. His group currently consists of 30 scientists, with expertise in bioinformatics, systems biology, clinical research and microbiology. He has a substantial track record in microbiome research and has been pioneering the analysis and integration of meta-omics datasets (metagenomics, metatranscriptomics, metaproteomics, meta-metabolomics) with environmental, clinical, host omics and dietary data. He was involved in the FP7 MetaHIT and NIH Human Microbiome Project (the latter as only European partner), which laid the foundations for the human microbiome field as it is today. Finally, his lab is performing a wide range of disease-related projects in a.o. IDB, diabetes, cancer, IBS and antibiotics resistance and develops novel approaches and tools for microbiome research. Jeroen Raes coordinates the Flemish Gut Flora project, a large scale microbiome- focused population cohort in Belgium, and is bioinformatics coordinator in the Tara Oceans project performing large-scale meta-omics analysis of plankton communities.

Interactive effects of the microbiome and nutrition on mucosal physiology and functions in the porcine intestinal tract.
Barbara Metzler-Zebeli, University of Veterinary Medicine, Vienna

Due to their presence and metabolic activity, the gut microbiota influences growth-related, but also health-related traits such as immune competence and tolerance. An appropriate nutrient balance is important for the health and well-being of the pig as well as for the maintenance of a stable gut microbiota. By acting as mucosal immune stimulants, the alterations in microbiota-associated molecular patterns due to diet-associated taxonomic shifts may play a greater role for host physiology and health than functional differences in the microbiome caused by dietary shifts. This talk will give an overview about the impact of alterations related to pig’s mineral and carbohydrate intake on the microbial taxonomy and functional metabolism in monogastric livestock species and delineate the consequences that changes in microbial abundances and fermentation activity have for host mucosal functioning and beyond.

Prof. Barbara Metzler-Zebeli is professor of Nutritional Physiology at the University of Veterinary Medicine Vienna in Austria. She completed a PhD in Feed Sciences in 2007 at the University of Hohenheim, Stuttgart, Germany. After research stays at the University of Alberta (Edmonton, AB, Canada) and the Leibniz Institute for Farm Animal Biology (Dummerstorf, Germany), she joined the University of Veterinary Medicine Vienna in 2011 and became the head of the unit “Nutritional Physiology” in 2019. Her main research focus is on the mechanisms underlying the diet – gut microbiome – host interactions and gut health in livestock animals. Current research topics encompass the diet-sow-piglet-axis, microbial-gut mucosal signaling, the evaluation of gut modulatory capacity of functional feed (i.e. carbohydrates, phytobiotics and minerals) and technological approaches to improve the nutritional quality and functionality of feed. Barbara has published more than 120 papers in peer reviewed journals and has given numerous invited talks at international symposia.

The role of the gut in whole-body functioning

Microbes, metabolites and the gut-lung axis
Ben Marsland, Monash University, Melbourne

The microbiota plays an essential role in the education, development, and function of the immune system, both locally and systemically. Emerging experimental and epidemiological evidence highlights a crucial cross-talk between the intestinal microbiota and the lungs, termed the ‘gut–lung axis’. Changes in the constituents of the gut microbiome, through either diet, disease or medical interventions (such as antibiotics) is linked with altered immune responses and homeostasis in the airways. The importance of the gut–lung axis has become more evident following the identification of several gut microbe-derived components and metabolites, such as short-chain fatty acids (SCFAs), as key mediators for setting the tone of the immune system. Recent studies have supported a role for SCFAs in influencing hematopoietic precursors in the bone marrow—a major site of innate and adaptive immune cell development. Prof. Marsland will present their current understanding of host–microbe cross-talk along the gut–lung axis, highlighting the importance of SCFAs in shaping and promoting bone marrow hematopoiesis to resolve airway inflammation and to support a healthy homeostasis.

Prof. Ben Marsland is professor in the Department of Immunology and Pathology, within the Central Clinical School at Monash University. He completed his PhD in Immunology at Otago University and the Malaghan Institute of Medical Research, Wellington, New Zealand. He then spent 14 years in Switzerland, first at the ETH Zürich and then as a Cloetta Medical Research Fellow at the University Hospital of Lausanne (CHUV). During that period, he received the ETH Latsis Prize, the Leenaards Prize and the ERS COPD Research Award. Since 2018, Ben is a veski innovation fellow, NHMRC Senior Research Fellow and Professor at Monash University. He also maintains a visiting professorship at the University of Lausanne and CHUV. The focus of Ben’s lab revolves around the microbiome in the gut, lung and skin and how it influences asthma, respiratory viral infections and lung fibrosis.

Born too early or born too little, – how to adapt to postnatal life under these conditions?
Thomas Thymann, University of Copenhagen

Whole-body adaptation to postnatal life is a prerequisite for acute survival and prevention of later disease. Active respiration, thermoregulation, immune activation and gut colonization represent a few of these important adaptational processes. For a number of years, he has studied factors that influence early life adaptation, particularly after preterm birth where the need for optimal rearing conditions is even more crucial. This model can be used to study relevant interventions that may benefit both preterm neonatal infants, and compromised weak piglets.

Prof. dr. Thomas Thymann, DVM, is professor in Comparative Pediatrics and Nutrition at the Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences of the University of Copenhagen in Denmark since 2018. He received his MSc, DVM and PhD degrees at the University of Copenhagen. He has developed specialized animal models to reflect human and animal disease. His main focus areas include diet-induced inflammation and compromised organ function in early life. Specifically, advanced animal models of premature birth have been developed and refined to study effects of microbial, nutritional and medical interventions. The interventions include probiotics, fecal transplant, parenteral nutrition, enteral milk diets, colostrum and other biological fluids. Clinical and laboratory endpoints include clinical manifestations, cognition, organ pathology, nutrient absorption, histopathology, digestive enzymes, microbiology and markers of sepsis and gut failure. His teaching experience includes a Pathology and Pharmacology course, and supervision of PhD and master students.

Models and methodologies

Modelling of metagenomic data for understanding of the functional microbiome.
Bas Dutilh, Utrecht University

Metagenomics has revolutionised biology. By sequencing genetic material directly from the environment, it has enabled the analysis of organisms that previously could not be detected, let alone studied in detail. Moreover, by providing an systems-level, genome-resolved view of the organisms in an environment, metagenomics provides unprecedented insights into the composition and functioning of the natural microbial world. Dr. Dutilh will present some of their recent results on computational analysis and modelling of metagenomic datasets, with a focus on making measurable and interpretable the complex factors that drive the microbiome.

Dr. Bas E. Dutilh is associate professor and PI of the Utrecht University Metagenomics Group (MGX). MGX pursues understanding of the complex interplay between metabolism, ecology, and evolution that shapes microbiomes by studying big datasets such as metagenomes. To do this, they develop and apply innovative tools to discover unknown microbes/viruses, describe their functionality, chart community interactions, build predictive models to integrate and understand data, and design interventions. These tools include meta’omics experiments, integrative bioinformatics, and quantitative mathematical/computational models. Advances are expected from tools that address or exploit high microbial/viral diversity, the dynamical complexity in natural microbiomes, and biological/methodological noise in the data. Dutilh is founding member of the EVBC, founder of the Netherlands Metagenomics Platform, Chair of the Metagenomics Study Group and elected member of the Executive Committee at the International Committee for Taxonomy of Viruses (ICTV), and Chair of the Microbial Bioinformatics Section at the Royal Netherlands Society for Microbiology (KNVM). He has co-authored over 100 publications.