Harnessing microcins for control of scours in neonatal calves

Calf diarrhea (scours) is a major animal health challenge for cattle producers because it causes dehydration, depression, mortality, and long-term reduction in vitality of infected animals. Enterotoxigenic E. coli (ETEC; K99) and enterohemorrhagic E. coli (EHEC; e.g., serovars O157:H7, O26 and O111) can cause enteric colibacillosis in calves, and EHEC strains are also significant food safety pathogens. We have discovered a novel microcin that is capable of killing both ETEC and EHEC E. coli. In this project, which directly addresses the BIOAg “Livestock and Animal Health” priority for FY12, we will use a neonatal calf model to determine if inoculation with microcin producing E. coli can inhibit colonization by E. coli K99, O157:H7, O111, and O26 strains. Our second objective will identify the target receptor that is required for susceptibility to the microcin and this will be mostly supported using funds from an existing grant. These steps are needed to demonstrate the feasibility of a microcin control strategy and thereby leverage new extramural grant and industry investment in this novel system. If microcin-producing strains can be employed as either prophylactic or therapeutic applications, this could be a relatively low-cost disease control strategy that is consistent with the aims of BIOAg. This project will also support completion of a Ph.D. thesis and, if successful, will support development of new intellectual property for Washington State University.