Footbath to prevent lameness in sheep (PhD)

The Project

Lameness in sheep is a major welfare concern for both sheep farmers and veterinarians in the UK. In 2004 the prevalence of lameness in England was 10.6%, with more than 90% of lameness attributed to footrot.

In the UK footbaths are an essential component of infectious lameness control. It is specifically recommended as part of the five-point-plan to treat large number of lambs with ID/scald by AHDB Beef & Lamb. However, there is very little information on the efficacy of footbathing in UK in relation to how, when and how often it should be practiced, or the relative efficacy of the variety of active ingredients when applied using different management protocols. This knowledge gap prevents lamb producers from making a truly informed decision on an appropriate lameness prevention strategy for their farming system.

The notable reduction in the average prevalence of footrot and lameness achieved over the past ten years is partly a result of the adoption of injectable antibiotic treatment for footrot. This improvement in animal welfare may be compromised in the future by regulatory restrictions or limitations on the use of such antibiotics in the sheep industry as part of a wider emphasis on reducing antibiotic usage in farming systems. The role of non-antibiotic footbaths and footbathing protocols as a preventative control measure is therefore essential as the industry may be forced to become less reliant on injectable antibiotics. Preliminary data suggests that a period of frequent footbath treatments with short intervals has a substantial positive impact on microbial community and the incidence of clinical footrot and CODD.

The Challenge

The overall aim of this project is to reduce the overall reliance on injectable antibiotics for the control of ID and footrot by developing optimal footbath protocols for the different seasonal time points in sheep husbandry.

The objectives are:

• To investigate by questionnaire and interview the current footbathing practices of commercial sheep producers
• To investigate the impact of all currently available footbath active ingredients: Formalin/formaldehyde, glutaraldehyde, zinc sulphate and organic acids each at a variety of concentrations and exposure times on the microbial community, species diversity and population structure of the ovine foot
• To investigate the impact of footbath protocols (eg. frequency of footbathing, duration in the bath, prior level of hoof contamination) on the microbial community of the interdigital space
• To investigate the concentration/inactivation dynamics of footbath chemicals with the number of animals treated to provide practical, independent guidelines on the different footbathing protocols
• To investigate the impact of the seasonality and environmental conditions (temperature, moisture) on the efficacy of the protocols tested in objective 3 in spring, midsummer and prior to housing on the microbial community of the ovine foot
• To investigate the relative intrinsic effects of different footbath preparations on the inflammatory response in the interdigital space and the penetration of the bacteria and footbath active ingredient into the skin and hoof horn

A sample of 40 sheep farms from across England and Wales currently participating in a production benchmarking trial will be interviewed in depth on their current practice and experience of using footbaths focusing on the practical and perceived limitations in their use. This in-depth qualitative analysis will be accompanied by a wider, shallower survey of footbath usage amongst NSA members as a convenience sample of sheep producers. 

Microbial viability pre and post-footbathing for every commercially available product and control solutions will be investigated on a large number of feet obtained from abattoirs.

Trials on commercial sheep flocks will be used to test and develop practical guidance with swabs being collected from feet to understand the impact on the microbial communities

Student

Hayley Marshall