Effect of chronic and acute enterotoxigenic E. coli challenge on growth performance, intestinal inflammation, microbiome, and metabolome of weaned piglets

Abstract

Post-weaning enteropathies in swine caused by pathogenic E. coli, such as post-weaning diarrhea (PWD) or edema disease (ED), remain a significant problem for the swine industry. Reduction in the use of antibiotics over concerns of antibiotic resistance and public health concerns, necessitate the evaluation of effective antibiotic alternatives to prevent significant loss of livestock and/or reductions in swine growth performance. For this purpose, an appropriate piglet model of pathogenic E. coli enteropathy is required. In this study, we attempted to induce clinical signs of post-weaning disease in a piglet model using a one-time acute or lower daily chronic dose of a pathogenic E. coli strain containing genes for both heat stable and labile toxins, as well as Shiga toxin. The induced disease state was monitored by determining fecal shedding and colonization of the challenge strain, animal growth performance, cytokine levels, fecal calprotectin, histology, fecal metabolomics, and fecal microbiome shifts. The most informative analyses were colonization and shedding of the pathogen, serum cytokines, metabolomics, and targeted metagenomics to determine dysbiosis. Histopathological changes of the gastrointestinal (GI) tract and tight junction leakage as measured by fecal calprotectin concentrations were not observed. Chronic dosing was similar to the acute regimen suggesting that a high dose of pathogen, as used in many studies, may not be necessary. The piglet disease model presented here can be used to evaluate alternative PWD treatment options.

Significance of Mucosa-Associated Microbiota and Its Impacts on Intestinal Health of Pigs Challenged with F18+ E. coli

“…The F18 + E. coli is highly prevalent in pigs causing post-weaning diarrhea (PWD) [ 14 , 16 ]. The PWD caused by enterotoxigenic E. coli infection is well known to induce microbiota dysbiosis [ 17 , 18 , 19 ]. During infection, the increased nitrate and oxygen concentration may increase the proliferation of aerobic and facultative anaerobic bacteria, and reduce anaerobic bacteria [ 18 , 20 , 21 ].…”

The Effects of Grounded Herbs on the Intestinal Villus Height and Shedding of F18-positive Escherichia coli in Weaned Pigs

“…Even after the E. coli challenge was stopped, hemolytic E. coli shedding continued to grow. This scenario indicated the colonization and proliferation of inoculated E. coli in the gastrointestinal tracts of swine (Boeckman et al, 2022). In addition, inoculated E. coli induced diarrhea after the first day of inoculation.…”

“…This experiment simulated the common real-life situation in which pigs on farms become sick from E. coli and shed the bacteria at about 10 8 CFU per gram of feces into the environment (Frydendahl et al, 2003;Boeckman et al, 2022). Pigs in close contact inevitably consume this amount of E. coli, colonizing the swine's gastrointestinal tracts and proliferating.…”

Landscapes of Enteric Virome Signatures in Early-Weaned Piglets

“…The results of that study suggest that the enteric virome can affect intestinal homeostasis and IBD by modulating the innate immune response ( 38 ). Early-weaning-induced stress has been widely demonstrated to cause intestinal inflammatory responses in piglets ( 39 – 41 ). A previous study provided preliminary insights into the relationship between the enteric virome and diarrhea in neonatal piglets of commercial production systems ( 42 ).…”