Development of a conventional pig model for Clostridium difficile infection and associated disease in neonatal pigs

Abstract

The purpose of this study was to reproduce Clostridium difficile-associated disease (CDAD) using conventional pigs as an animal model and to determine whether different disease outcomes occur with isolates of human and porcine origin. Piglets were snatch farrowed from a conventional sow farm where they were given pooled colostrum and then transported to a research facility. At four hours of age, 26 conventional pigs were oralgastrically inoculated with one of four different isolates of C. difficile and 6 control pigs were sham-inoculated. All challenge isolates were toxinotype V; three were isolated from clinical field cases of diarrhea in neonatal pigs in Illinois or Missouri, and the fourth isolate was of human origin. All pigs were individually housed and randomly selected for necropsy at 24, 48, or 72 hours post infection (hpi). The results of this study show that C. difficile was isolated from all pigs, inoculated and uninoculated. Commonly observed lesions and indications of CDAD, including mesocolonic edema, toxin detection, diarrhea, neutrophilic infiltration of the colonic and cecal lamina propria, as well as mucosal ulceration or erosion of the colon and cecum were observed in challenged pigs. No difference in disease between the human and porcine isolates was observed. Clinical signs and lesions were observed in some controls and these pigs may have been inadvertently contaminated. The data generated in this study provide evidence that this can be an effective challenge model.