Mapping the expanding host range of digital dermatitis treponemes
Digital dermatitis is a bacterial infection which produces severe foot lesions in infected animals causing substantial suffering and significant economic loss. It affects 1.2m dairy cattle annually in the UK alone. University of Liverpool researchers aimed to characterise the bacteria causing bovine digital dermatitis and the transmission routes in order to enable future methods to control the disease.
The majority of evidence clearly identifies bacteria known as 'Treponema' as the common cause of bovine digital dermatitis (BDD). In previous studies we clarified the association of these bacteria with BDD and characterised these causal bacteria into three distinct groups. We developed novel PCR diagnostics for the DD treponemes which have widely been applied for diagnostic testing of the disease (1). These PCR diagnostics allowed us to track the continued emergence of the disease in new hosts including sheep, beef cattle, and wild elk and in new countries (Ireland, Germany, USA) (2-4). Multi locus sequence typing of a large panel of strains (n=121) from multiple hosts and continents demonstrated that the same bacterial strains appear to be transmitted between different host species although human strains appear to have evolved separately (5). We have also implicated the GI tract as an infection reservoir in dairy and beef cattle and sheep (6).
Characterisation of the bacteria considered causal of these diseases and clarification of transmission routes should enable future control methods to tackle this severe infectious disease of ruminants.
Research outputs
- Evans, N. J., Brown, J. M., Demirkan, I., Singh, P., Getty, B., Timofte, D., Carter, S. D. (2009). Association of Unique, Isolated Treponemes with Bovine Digital Dermatitis Lesions. Journal of Clinical Microbiology, 47(3), 689-696. DOI: 10.1128/JCM.01914-08
- Sullivan, L. E., Clegg, S., Angell, J. W., Newbrook, K., Blowey, R. W., Carter, S., . . . Evans, N. (2015). High-Level Association of Bovine Digital Dermatitis Treponema spp. with Contagious Ovine Digital Dermatitis Lesions and Presence of Fusobacterium necrophorum and Dichelobacter nodosus. Journal of Clinical Microbiology, 53(5), 1628-1638. DOI: 10.1128/JCM.00180-15
- Clegg, S., Mansfield, K., Newbrook, K., Sullivan, L., Blowey, R., Carter, S., & Evans, N. 2015 Isolation of digital dermatitis treponemes from hoof lesions in wild elk in Washington State, USA. Journal of Clinical Microbiology, 53(1):88-94. DOI: 10.1128/JCM.02276-14
- Tegtmeyer, P. C., Staton, G. J., Evans, N. J., Rohde, J., Punsmann, T. M., & Ganter, M. (2020). First cases of contagious ovine digital dermatitis in Germany. Acta Veterinaria Scandinavica, 62(1). DOI: 10.1186/s13028-020-00544-0
- Clegg, S. R., Carter, S. D., Birtles, R. J., Brown, J. M., Hart, C. A., & Evans, N. J. (2016). Multilocus Sequence Typing of Pathogenic Treponemes Isolated from Cloven-Hoofed Animals and Comparison to Treponemes Isolated from Humans. Applied and Environmental Microbiology, 82(15), 4523-4536. DOI: 10.1128/AEM.00025-16
- Sullivan, L. E., Carter, S. D., Duncan, J. S., Grove-White, D. H., Angell, J. W., & Evans, N. J. (2015). The Gastrointestinal Tract as a Potential Infection Reservoir of Digital Dermatitis-Associated Treponemes in Beef Cattle and Sheep. Applied and Environmental Microbiology, 81(21), 7460-7469. DOI: 10.1128/AEM.01956-15
Funding
BBSRC RM Grant: Dissecting the molecular diversity and commonality of the bovine digital dermatitis treponemes. New Investigator Award: N. Evans (PI).
BBSRC RM Grant: Host-Pathogen interactions of treponemes and hoof tissues in digital dermatitis: How does infection lead to lameness. S. Carter (PI), R. Birtles, N. Evans (Researcher Co-I)
AHDB Dairy/DairyCo Funded Studentship: Identifying how digital dermatitis is transmitted between dairy cows. Supervisors: N. Evans (Lead), R. Murray & S. Carter, Student: Jennifer Bell.
AHDB Beef and Lamb/HCC/QMS Funded Studentship: Identifying digital dermatitis infection reservoirs in beef cattle and sheep. Supervisors: N. Evans (Lead), J. Duncan, D. Grove-White & S. Carter, Student: Leigh Sullivan.