Distribution of Treponema species and antimicrobial resistance genes in digital dermatitis lesions
| dc.contributor.advisor | De Buck, Jeroen M. | |
| dc.contributor.author | Beninger, Caroline | |
| dc.contributor.committeemember | Orsel, Karin | |
| dc.contributor.committeemember | Morck, Douglas W. | |
| dc.date | 2018-11 | |
| dc.date.accessioned | 2018-08-07T19:18:57Z | |
| dc.date.available | 2018-08-07T19:18:57Z | |
| dc.date.issued | 2018-08-04 | |
| dc.description.abstract | Digital dermatitis lesions are ulcerative or proliferative masses between the heel bulbs. The most significant clinical outcome of digital dermatitis (DD) is lameness, leading to animal welfare concerns and economic loss for dairy producers worldwide due to premature culling, milk loss, and decreased fertility. While there is insufficient evidence to determine the etiological agent(s) responsible for DD, it is widely accepted that DD is a polymicrobial disease significantly associated with anaerobic bacteria, Treponema. Difficulties in obtaining pure cultures and the nearly exclusive presence of Treponema in diseases as members of a polytreponemal or polymicrobial communities has led to insufficient species identification within lesions and incomparable prevalence estimates based on phylotype. Our primary research objectives were to develop a diagnostic tool to identify Treponema spp. within DD lesions to associate presence and abundance with DD lesion grades. Further, we examined the distribution of antimicrobial resistance genes (AMGs) within sequenced isolates of DD-associated Treponema and designed targeted PCR for Treponema AMGs (AMGsTrep) within lesions. We provide significant evidence that the absolute quantities of Treponema and AMGsTrep are lower in chronic and early, active DD lesions suggesting Treponema spp. within these lesions may be more susceptible to antimicrobials (AMs) compared to species in advanced, active lesions. We have identified potential interactions among Treponema spp. that may facilitate DD progression and enhance pathogenicity and may affect AM susceptibility and lesion chronicity. With the novel diagnostic tool developed here, future research should elucidate interactions among Treponema spp. and in vitro susceptibility profiles and the efficacy of treating early and chronic lesions compared to advanced, active lesions on infection resolution. | en_US |
| dc.identifier.citation | Beninger, C. (2018). Distribution of Treponema species and antimicrobial resistance genes in digital dermatitis lesions (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/32795 | en_US |
| dc.identifier.doi | http://dx.doi.org/10.11575/PRISM/32795 | |
| dc.identifier.uri | http://hdl.handle.net/1880/107613 | |
| dc.language.iso | eng | |
| dc.publisher.faculty | Graduate Studies | |
| dc.publisher.faculty | Veterinary Medicine | |
| dc.publisher.institution | University of Calgary | en |
| dc.publisher.place | Calgary | en |
| dc.rights | University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. | |
| dc.subject | Digital dermatitis | |
| dc.subject | Treponema | |
| dc.subject | qPCR | |
| dc.subject | Antibiotic resistance | |
| dc.subject | polymicrobial | |
| dc.subject | Lameness | |
| dc.subject.classification | Genetics | en_US |
| dc.subject.classification | Microbiology | en_US |
| dc.subject.classification | Veterinary Science | en_US |
| dc.title | Distribution of Treponema species and antimicrobial resistance genes in digital dermatitis lesions | |
| dc.type | master thesis | |
| thesis.degree.grantor | University of Calgary | |
| thesis.degree.name | Master of Science (MSc) | |
| ucalgary.item.requestcopy | true |