Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/18/2007
Publication Date: 10/20/2007
Citation: Rettedal, E., Scupham, A.J. 2007. Examination of the intestinal microbiome for identification of functionally important species [abstract]. International Symposium on Animal Genomics for Animal Health. Paper No. 79.
Technical Abstract: Objectives of these studies were to describe the constituents and dynamics of intestinal bacterial communities in turkeys, and identify microbes associated with exclusion of the food borne pathogen Campylobacter jejuni. It has been estimated that >7000 bacterial subspecies reside in the intestine, affecting host nutrition and health. Our surveys of the turkey intestinal microbiota using oligonucleotide fingerprinting of rRNA genes (OFRG) and 16S rDNA sequencing indicated communities were dominated by Bacteroidetes and Clostridiales, although most of the species have not yet been cultivated. We showed that as the birds age, cecal communities become increasingly anaerobic, with a substantial shift towards the Bacteroidetes around eleven weeks. To identify pathogen-excluding species, day-old turkey poults were inoculated with cecal contents from a C. jejuni-free adult and housed in isolation chambers. Each group was treated with a single antibiotic to select for unique subpopulations. After community selection, the birds were challenged with C. jejuni and plate counts were performed to quantify the pathogen. Compared to the untreated control group harboring 2.5 x 10**7 cfu/g of C. jejuni in the ceca, the virginiamycin treated group contained 1 x 10**9 cfu/g while enrofloxacin, neomycin, and vancomycin groups held 6 x 10**6, 3 x 10**5, and < 10**3 cfu/g. Differential microbial populations are being described by OFRG. These preliminary results indicate that identification of species that inhibit C. jejuni is possible, and these methods can be used to describe constituents of the microbiota that perform desired functions relating to other facets of animal health.