Postdoctoral Scientists – The Engine of Research

By Mingan Choct

In this issue of Poultry@Sydney, I would like to introduce our three new postdoctoral scientists, Drs Eunjoo Kim, Irene Li and Lee Campbell.

Dr. Eunjoo Kim’s focus is fibre nutrition. She completed her PhD in poultry nutrition in 2022 at the University of New England. Her PhD research revealed that over 30% of broiler feed goes wasted, highlighting significant opportunities for improvement. She identified indigestible components in poultry diets across different growth stages and explored strategies to minimize these losses.

Eunjoo is particularly passionate about fibre nutrition in poultry—an often-overlooked dietary component that, despite being largely indigestible, plays a key role in gut health and feed efficiency. After completing her PhD, she joined Poultry Hub Australia as a postdoctoral researcher, further expanding her expertise in poultry fibre nutrition. Her research focused on converting indigestible fibre into bioactive compounds, which can enhance bird health and overall feed utilization.

Her work has demonstrated that supplementing poultry diets with fermentable fibre sources and tailored fibre-degrading enzymes can positively shape the gut microbiome, enhance feed efficiency, and ultimately contribute to more sustainable chicken meat production.

“Fibre is a fundamental component of plant-based poultry feed and interacts with key nutrients like starch and protein. But, its structural complexity and impact on gut health remain largely overlooked. My goal is to unlock the full potential of fibre by optimising its dietary levels and developing substrate-based enzyme strategies for industry applications.”

In August 2024, Eunjoo joined PRF at The University of Sydney, where she is excited to expand her research, gain new knowledge and continue exploring for the role of fibre in poultry nutrition.

Dr Irene (Jiasui) Li’s interest is poultry microbiota. Irene received her PhD training in marine microbiology and ecology at the University of New South Wales, mentored by Prof. Suhelen Egan, Prof. Torsten Thomas, and Assoc. Prof. Ziggy Marzinelli.

Irene’s passion for microbial ecology was ignited during her MSc thesis, where she characterized fungal pathogens responsible for root-rot disease in a cultivated Chinese herb. The multifaceted nature of etiological agents fascinated her. This interest motivated her to pursue her PhD research, which revealed the crucial roles of microbiota associated with marine macroalgae (seaweeds) in enhancing disease resistance of algal hosts when exposed to opportunistic pathogens and under suboptimal conditions.

‘Host-associated microbiota can be considered as an extension of the holobiont (eukaryotic macroorganism plus symbiotic microbiota) host’s function and ecological service potential. Understanding the importance and functional contributions of the microbiota is essential for unlocking the full potential of the holobiont host to withstand suboptimal environments, which are becoming increasingly prevalent due to global changes and resource constraints’, replied Irene when I asked her about her work.

Her research demonstrated that microbiota manipulation by inoculating the host with specific bacteria is a feasible tool to mitigate dysbiosis caused by opportunistic pathogens and environmental stress.

Irene joined PRF in September 2024, working with Assoc. Prof. Sonia Liu and Assoc. Prof. Andrew Holmes. Her current research focuses on the interactions between diets and chicken gut microbiota, and their effects on animal growth performance and feed efficiency, aiming to enhance productivity and reduce environmental and resource burdens.

Dr. Lee Campbell is a comparative immunologist who specializes in avian immunology and the evolution of avian immune genes. She completed her PhD at the University of Alberta in Canada, where she studied the immune response of ducks to both high and low pathogenic avian influenza virus. Her research focused on comparing the global immune response of ducks to humans and chickens. A central aspect of her PhD work was understanding how immune gene families have evolved between species, and how these evolutionary changes contribute to resistance or susceptibility to infections.

During Dr. Campbell’s postdoctoral tenure at the University of Sydney, she plans to continue investigating the cellular immune response of ducks to influenza A virus, particularly to that of low pathogenic avian influenza, which replicates to incredibly high titres in the duck without damaging tissues or making them sick. Her future aspirations are to repeat these experiments in chickens to see the differences between them (the susceptible host) and ducks (the resistant and tolerant host). During her postdoc she also plans to create cell lines of iconic Australian wildlife, such as black swans, and test the cellular response of these lines to influenza A virus.