The impact of glutaraldehyde based footbaths on Dichelobacter nodosus prevalence and the antimicrobial resistant community of the ovine interdigital skin

Ovine footrot, is a highly contagious polymicrobial bacterial infection, primarily caused by Dichelobacter nodosus. Preventative bactericidal footbaths are commonly used in the sheep industry to reduce the spread of bacteria. However, their effect on the bacterial community is poorly understood. This is the first study to investigate the impact of 2% Digicur (ProGiene,UK) footbath on the bacterial community of the ovine interdigital skin following a common UK footbathing routine. Swab samples were analysed by qPCR to determine prevalence and load of D. nodosus and numerated on MacConkey agar in the presence or absence of tetracycline and ampicillin to determine phenotypic antimicrobial resistance. Metagenomics were used to determine the impact of a single footbath on the bacterial community and genotypic antimicrobial resistance. The results suggest 2% Digicur is ineffective at reducing the load of D. nodosus when applied as a one off or weekly footbath, however sheep may act as a reservoir for multi-drug resistant bacteria creating opportunities to spread antimicrobial resistance to other sheep and their environment.