I study host-pathogen interactions and the impact of infectious disease control interventions (e.g. vaccination and antimicrobial use) on cattle health. My work is motivated by practical concerns of dairy cattle health on food production, and encompasses epidemiology, molecular genetics, microbiology and immunology. I am interested in economically significant diseases of dairy cattle that affect productivity and ultimately human health and well-being through food availability. I am also interested in epidemiology and host specificity of infectious diseases at the human-animal interface. Broadly, my research interests involve the intersection between epidemiologic and molecular genetic approaches to understand the population biology of host-pathogen relationships.
My current research program can be divided into 3 major activities:
I. Mastitis epidemiology and control – To characterize and broaden understanding of mastitis epidemiology and control practices through improvements of mathematical models, field studies, and intervention trials conducted on commercial dairy farms. Current studies emphasize epidemiology and control of major gram positive pathogens, especially Staphylococcus aureus on organic and conventional dairy farms in Vermont.
II. Host-adapted strains of Staphylococcus aureus associated with bovine mastitis – To characterize pathogen related factors influencing host-adaptation of Staphylococcus aureus bovine mastitis. The overall objective is to connect Staphylococcus aureus phenotype to genotype with the goal of improving our understanding of host-pathogen infection dynamics and developing improved control practices.
III. Cattle Major Histocompatibility Complex (MHC) genes and pathogen recognition (Bovine MHC [BoLA]) – To characterize allele diversity and frequency of the major histocompatibility complex (MHC) class I and class II genes within a herd of pure-bred registered Holstein dairy cattle (University of Vermont Research Herd). These genes are critical to the T-cell mediated immune response to intracellular pathogens including viruses (class I MHC) and to adaptive immune response mediated through antigen presenting cells (class II MHC). Tissue typing data for the MHC loci will be used to study the immune response of Holstein dairy cattle to Foot and Mouth Disease (FMD) virus. Specifically, by quantifying the extent of MHC diversity we will establish the potential for use of tetramer technology to study the immune response to FMD virus and a FMD vaccine candidate currently under development by USDA-ARS.