LAUSR

Although we have known that footrot is a contagious disease for over 200 years (Graham and Egerton, 1968), it is only in the past decade or so that we have really started to build a high quality evidence base to guide treatment and management of this disease. Much of this is down to Laura Green of the University of Warwick, Coventry, United Kingdom and her co-workers, who have shown that previous standard herd level methods of footrot control (routine foot trimming and footbathing) are associated with a higher prevalence of disease, whilst prompt individual treatment of lame sheep with parenteral and topical antibiotics, without foot trimming, reduces disease prevalence (Winter et al., 2015). Although this research has changed practice on many farms, there are still significant barriers to the acceptance of these new recommendations, particularly those related to ‘not foot trimming’, in both the veterinary and farming professions (Higgins et al., 2013; O’Kane et al., 2016). The paper by Winter and Green (2017), published recently in The Veterinary Journal, is to be welcomed as another tool to persuade veterinarians and farmers to change from old, inefficient and ineffective practices to new, proven methods. In their paper, the authors focus on the economics of footrot management and conclude that following recommended best practice would not only reduce the prevalence of footrot, but also save farmers an average of £4.651 per ewe per year (Winter and Green, 2017), a not inconsiderable sum when the feed and labour costs of the average lowland farm are ~£35.00 per ewe per year and veterinary costs are £2.50 per ewe per year (Boon et al., 2008). Even just treating promptly with antibiotics would save an average of £0.79 per ewe per year. However, this economic impact is based on the time taken for each procedure and its expected benefit, so it could be argued that the paper by Winter and Green just confirms that procedures that are ineffective and time consuming are not worth undertaking, and that it adds little to the previously published research. This argument misunderstands what influences farmer decision making. It can be clear to the veterinarian or other advisor that a course of action is not justified on efficacy grounds, but the same evidence will not be persuasive for the farmer. However, putting a figure on that lack of efficacy can be immensely persuasive, even though farmers are not simply ‘rational profit maximisers’ (O’Kane et al., 2016). The results of a survey of 1260 sheep farmers in 2013 (Winter et al., 2015) show that, although there is cause for optimism, in that global mean lameness prevalence has halved, there is still a considerable way to go to change routine management of footrot on sheep farms in the United Kingdom. In that survey, 56% of farms were still using routine foot trimming and 36% were using routine footbathing to control footrot. Although these proportions are lower than those from a similar survey in 2004 by Kaler and Green (2009), in which 76% of farms used routine foot trimming and 55% used routine footbathing, they still show that a significant proportion of farms are using time consuming procedures to control footrot, but which are actually associated with increased prevalence of lameness. Interestingly, the percentage reduction in the use of the two management practices from 2004 to 2013 is similar, even though foot trimming is considerably more time consuming and physically difficult than footbathing and, as Winter and Green (2017) show, results in higher overall costs due to lameness; using routine trimming increases lameness costs by £2.96 per ewe per year, whereas using footbathing increases costs by only £0.90 per ewe per year. Furthermore, in contrast to routine foot trimming, footbathing has been shown to be effective; Greber et al. (2016) were able to eliminate footrot by using footbathing alongside testing for virulent Dichelobacter nodosus, although their regime of 10 min of footbathing per ewe per week is not likely to be feasible on most commercial sheep farms in the United Kingdom. The continuing high percentage of farms using routine foot trimming, despite the evidence that, even when done properly (i.e. <1% of trimmed sheep bleeding after trimming), it does not reduce the prevalence of lameness (Winter et al., 2015), highlights the problem that a significant proportion of farmers seem to be reluctant to give up foot trimming, either as a treatment or for prevention, even though, when questioned, farmers would like to do less foot trimming to control footrot and farmers who use routine foot trimming are more likely to be dissatisfied with their foot management than farmers who do not use routine foot trimming (Wassink et al., 2010). Some of this resistance to change from farmers may be related to a similar reluctance of veterinarians to stop foot trimming (Higgins et al., 2013). Hopefully, one of the key outcomes of the publication of the analysis by Winter and Green (2017) will be more veterinarians and farmers recognising that routine foot trimming is an expensive waste of time and effort that could be better spent on active management and early treatment of footrot. Based on the previous impact of studies published by this research group, I am confident that it will.