Recipient Organization
IOWA STATE UNIVERSITY
S. AND 16TH ELWOOD
AMES,IA 50011
Performing Department
VETERINARY PATHOLOGY
Non Technical Summary
Post-weaning diarrhea (PWD) caused by the bacterium 'enterotoxigenic Escherichia coli' (ETEC) is an economically important disease in weaned piglets. Currently, antibiotics are used in the swine industry to control intestinal infections, including PWD in piglets. Recent studies have confirmed that disruption of the normal gut bacterial communities (gut microbiome) induced during weaning transition is a critical factor involved in the development of PWD. Disruption of the normal gut microbiome (gut dysbiosis) has been found to be invariably implicated in both initiation and clinical manifestation of PWD. Therefore, stabilizing the gut microbiome during the weaning transition could be an effective strategy for controlling PWD. Recently, fecal microbiome transplantation (FMT) has been shown to prevent gut-dysbiosis and control serious intestinal illnesses in humans. However, the application of these strategies is minimally explored in the swine industry. This proposal seeks to optimize FMT in swine and to understand the mechanisms by which it control gut dysbiosis and ETEC infection in weaning piglets. In this project, we will test our central hypothesis that gut microbiome dysbiosis and PWD in piglets could be prevented by the transplantation of adult pig gut microbiota of varying complexity. In the long term, our results will help to improve the rational design of defined gut bacteria mix as an alternative to antibiotics treatment in pigs. In summary, this project seeks to develop a gut microbiota based intervention as a non-antibiotic alternative to control PWD -a significant challenge is commercial swine production.
Animal Health Component
90%
Research Effort Categories
Basic
10%
Applied
90%
Developmental
(N/A)
Goals / Objectives
Project goals:Microbiome transplantation to prevent gut-dysbiosis and post-weaning diarrhea PWD in pigletsHusbandry practices associated with dietary and environmental changes and piglet weaning age are parameters that are not practical and not economical to change in commercial swine production. However, it is possible to control the post-weaning dysbiosis based on current microbiome research knowledge. fecal microbiota transplantation (FMT) has been widely used in human and veterinary medicine to treat a number of enteric diseases. These include diseases such as C. difficile infection (CDI), inflammatory bowel disease (IBD), ulcerative colitis, and Crohn's disease. Management of CDI in humans is the most notable example of the successful use of FMT as a radical therapeutic strategy against dysbiosis and enteric infections. PWD in piglets has similar pathogenesis as CDI in terms of gut-dysbiosis and subsequent pathogen colonization. Thus, stabilizing the gut microbiome by transplanting mature and healthy gut-microflora to weaning piglets could potentially prevent gut-dysbiosis and PWD. In this project, we will test our central hypothesis that gut microbiome dysbiosis and PWD in piglets could be ameliorated by the transplantation of adult pig gut microbiota of varying complexity. The following three objectives are designed to test this hypothesis.Objective 1: Determine the efficacy of fecal microbiome transplantation in preventing gut dysbiosis and PWD in piglets. In this objective, we will transplant fresh fecal suspension from 3-4-month-old pigs at early post-weaning stage. The fresh feces generally consist of several hundred species and represent highest microbiome complexity. We anticipate that this will have high efficiency in controlling PWD.Objective 2: Determine the efficacy of a bioreactor cultured microbiota preparation in preventing gut dysbiosis and PWD in piglets. The bioreactor cultured microbiome mix consists of about 100 species and represent medium microbiome complexity. We anticipate that this will have high to moderate efficiency in controlling PWD.Objective 3: Determine the efficacy of a defined microbiota mix in preventing gut dysbiosis and PWD in piglets. Here, we will determine whether a defined mix of 20 - 30 pig gut-derived bacteria can control PWD. The source of this mix is a well characterized pig microbiota culture library developed by our group. When compared to previous objectives, this mix is of lower complexity and may have moderate efficiency in controlling PWD.
Project Methods
MethodsDetermine the effect of fecal microbiome transplantation in preventing gut dysbiosis and PWD in piglets.Sixty-four suckling piglets weaned and weighed at three weeks of age will be randomly divided into four experimental groups (n=16 per group), which will be housed in individual pens with ad-libitum access to starter diet and drinking water. The treatment groups include: Control group, FMT control group (FMT), ETEC challenge control group (EC), and FMT+ETEC challenge group (FMT+EC). All ETEC challenged pigs will be confirmed to be genetically susceptible to F18 ETEC by genotype sequencing of the α (1,2) fucosyltransferase-1 gene according to previously published protocol at our collaborator and swine geneticist Dr. Tuggle's lab at ISU. FMT and FMT+EC group will be provided with a fecal microbiome mix (5 mL solution orally) on the 1st and 3rd day of the experiment (1st and 3rd day of weaning) by direct oral gavage. On approximately day 10th of the study (10th day postweaning), animals in EC and FMT+EC groups will be inoculated with approximately 1010 CFU of bacteria (F18 positive ETEC clinical isolate). Control groups will be orally gavaged with PBS. Animals will be weighed and observed for diarrhea for eight days, and fecal samples will be collected at different time points (0, 2, 4, and 7-dpi). The number of pigs showing diarrhea will be recorded daily throughout the duration of the study. Six piglets each will be sacrificed on 4th and 8th day post-infection and the serum sample, intestinal tissue, and fecal material (from jejunum, ileum and colon) will be collected for histopathology, microbiome analysis, serology, SCFA analysis and ETEC quantitiation as per standard protocol.Determine the efficacy of a bioreactor cultured microbiota preparation in preventing gut dysbiosis and PWD in pigletsWe will use the following four experimental groups in this objective: Group 1 - Untreated control, Group 2- Standardized microbiota inoculation, Group 3- Standardized microbiota inoculation and ETEC challenge, Group 4- ETEC challenge. The overall sampling and analysis scheme will be the same asin objective 1. The difference in this experiment will be that instead of fresh fecal microbiota transplantation, groups 2 and 3 will receive the same CFU of bioreactor cultivated fecal microbiota preparation. Since the experimental parameters are similar, we will use the same number of animals/group as per the power analysis described in objective 1. We will collect samples for ETEC enumeration, histopathological evaluation, molecular biology evaluation, and microbiome analysis using the same protocols described in objective 1.Determine the efficacy of a defined microbiota transplantation in preventing gut dysbiosis and PWD in piglets.Here, we will use the same pig experiment outline used in objectives 1 and 2. The following four experimental groups will be used: Group 1 - Untreated control, Group 2- Defined bacteria inoculation, Group 3- Defined bacteria inoculation and ETEC challenge, and Group 4- ETEC challenge. The overall sampling and analysis scheme will be the same as in objective 1. Since the experimental parameters are similar, we will use the same number of animals/group as per the power analysis described in objective 1. We will collect samples for ETEC enumeration, histopathological evaluation, molecular biology evaluation, and microbiome analysis using the same protocols described in objective 1.