He has published more than 20 scientific research papers, a book chapter, and more than 100 abstracts, poster presentations, health column answers and lay articles.
He was awarded the Young Elite Scientist Award from the Danish Research Council in 2009.
Born in Denmark, Nielsen completed his veterinary degree at The Royal Veterinary and Agricultural University in Denmark in 2001. Renowned parasitologist Dr Peter Nansen was based there and Nielsen found it easy to fulfill his interest in parasite research with his first student projects.
When he got a job as an equine veterinarian, he was then asked to develop a worm programme for local horse-owning clients.
He got some good experience in the field, he says, and soon discovered there were good and bad habits surrounding worm management practices. Many questions asked by his clients could not be answered with the scientific evidence available at the time, and he became determined to dig deeper in search of solutions.
He completed his doctorate at the University of Copenhagen in 2007, researching parasite infections in horses, focusing on diagnosis, surveillance and control.
Nielsen says the issue of drug resistance in parasites poses a challenge not only to scientists, but also to horse owners in their management of worm burdens. His research to date has included a study of Strongylus vulgaris – work which took him to the Gluck Equine Research Center in Kentucky.
Nielsen’s United States research enabled him to discuss and collaborate on work with scientists such as Eugene Lyons and Ray Kaplan – men who are as close as you are ever likely to get to household names in the field of parasitology.
Nielsen joined the Gluck Center in August, 2011.
Before joining the University of Kentucky, Nielsen was an assistant professor at the Department of Large Animal Sciences, University of Copenhagen, where he taught several classes, advised graduate students, was a member of the night duty emergency team, and was a leader of the large animal clinical service and research laboratory.
His research interests include endoparasite infections of horses, clinical and molecular diagnosis, epidemiology, surveillance, and control.
Nielsen rides and his wife, Shaila Ann Sigsgaard, is an equestrian journalist.