Optimizing an infection model for E. coli diarrhea in newly weaned pigs

Project 21-02 - Dr. Vahab Farzan

Dr. Vahab Farzan, University of Guelph

Post-weaning diarrhea caused by enterotoxigenic E. coli (ETEC) in pigs is a widespread problem with high rates of mortality and morbidity. The most obvious impacts of post-weaning E. coli diarrhea are the economic losses, significant reduction in animal welfare, and indirect increase in use of antimicrobials. Post-weaning E. coli diarrhea is difficult to prevent. Sanitation and good management are not always effective and use of antibiotics and heavy metals have public health concerns. Probiotics, organic acids, and vaccination are now being considered as an alternative method to control post-weaning E. coli diarrhea in pigs. However, a precise infection model is required to evaluate the potential impact of those alternative methods on controlling postweaning E. coli diarrhea in pigs. One of the issues in the E. coli challenge model is there is a considerable variation in piglet responses to ETEC diarrhea because there are two porcine phenotypes, with pigs being either resistant or susceptible to ETEC diarrhea. In addition to pig susceptibility, other elements such as age and dosage of infection can affect pig response to ETEC challenge. The overall goal of this project is to conduct a series of challenge trials in the OVC Animal Isolation Facility to optimize an infection model for post-weaning E. coli diarrhea. Specifically, the association of genetic factor, age of pigs, and dosage of infection with severity of diarrhea, bacterial shedding, and tissue lesions in pigs challenged with ETEC will be examined.