Her researchcareer has focused on mucosal immunity, vaccines, immunogenetics and antibiotic alternatives. Dr. Lillehoj developed the first set of commercialized mouse monoclonal antibodies detecting chicken lymphocytes, constructed the first chicken intestinal cDNA microarray which has been of seminal importance in national and international poultry genomics research and developed and commercialized many novel antibiotic alternative strategies. Her research has resulted in more than 404 original papers, 20 book chapters, and 13 national and international patents. She has been awarded more than $ 20 million in research funding, including 8 CSREES NRI, BARD, IFASA, and Food Safety Initiative grants, and 45 formal collaborations (CRADAs) with private industry.