Naming and recognition of six foot lesions of sheep using written and pictorial information: a study of 809 English sheep farmers

In 2005, 3000 questionnaires were sent to a random sample of English sheep farmers from a list kept by the English Beef and Lamb Executive (EBLEX) to investigate whether farmers could correctly name six common foot lesions in sheep from a characteristic picture and a written description. The lesions were interdigital dermatitis (ID), footrot (FR), contagious ovine digital dermatitis (CODD), shelly hoof, foot abscess and toe granuloma. In addition, farmers were asked to report the total percent of lame sheep in their flock in 2004 and the percent of this lameness attributable to each of the six lesions listed above. The overall response percentage was 44 with a useable response of 32%. Fifty-nine farmers out of 262 (23%) who answered all six questions named all six lesions correctly. This was greater than expected by chance. The same questionnaire of six lesions was presented at a meeting of specialist sheep advisors, primarily veterinarians, 37/47 (79%) responders named all six lesions correctly. From the six lesions listed above, the percent correctly named by farmers was approximately 83%, 85%, 36%, 28%, 65% and 43% and the percent incorrectly attributed to another lesion was 5%, 47%, 10%, 13%, 35% and 7%, respectively. The most commonly used incorrect name was FR, with farmers tending to name any hoof horn lesion as FR. A comparison of the distribution of sheep lame by a lesion correctly named compared with the same lesion incorrectly named as FR suggested that farmers recognised lesions but did not name them correctly; the distribution of lameness fitted the pattern for the correctly named lesion rather than the pattern of lameness attributed to FR. The results were validated with farm visits and a repeatability study of the questionnaire. The mean farmer-estimated prevalence for all lameness was 10.4%; with 6.9%, 3.7%, 2.4%, 1.9%, 0.9% and 0.8% of the sheep lame with ID, FR, CODD, shelly hoof, foot abscess and toe granuloma respectively from respondents who correctly named these lesions. Whilst ID and FR were the most prevalent causes of lameness in most flocks it is possible that in up to 17% flocks the primary cause of lameness was a different lesion

Farmers' practices and factors associated with the prevalence of all lameness and lameness attributed to interdigital dermatitis and footrot in sheep flocks in England in 2004

The aim of this study was to investigate whether the risk factors associated with all causes of lameness in sheep differed from those associated with the lesion specific causes of lameness, interdigital dermatitis (ID) and footrot (FR). A total of 809 randomly selected English sheep farmers participated in a postal survey in 2005. Data were requested on their management of lameness in 2004 and whether this had changed from 2003 and the prevalence of all lameness, and lameness caused by ID and FR. The farmer ability to recognise ID and FR was assessed from their responses to a written and pictorial description. On 443 farms where both ID and FR were correctly named by the farmer, the mean prevalence of all lameness, and lameness caused by ID and FR were 10.0% (95% CI: 8.9, 10.8), 6.5% (95% CI: 5.8, 7.3) and 3.1% (95% CI: 2.8, 3.6), respectively. The mean prevalence of all lameness on all 809 farms was not significantly different at 10.2% (95% CI: 9.2, 11.0). The data were analysed using negative binomial regression models with the three outcomes farmer estimated prevalence of all lameness and lameness caused by ID or FR in 2004. Farmers who changed management of sheep between 2003 and 2004 were excluded from the analysis, thus all fixed effects were the farmers’ managements in 2003 and 2004 to ensure that the management was in place for at least one year before the prevalence estimates. Routine foot trimming ≥once/year compared with no routine foot trimming was significantly associated with an increased prevalence of all lameness (prevalence ratio (PR) = 1.34), ID (PR = 1.50) and FR (PR = 1.35). Footbathing was also significantly associated with increased prevalence of all lameness (PR = 1.67), ID (PR = 1.68) and FR (PR = 1.76). A stocking density of >8 ewes/ha was associated with a significantly increased prevalence of all lameness (PR = 1.26) and ID (PR = 1.39). There was a significantly lower prevalence of FR (PR = 0.73; PR = 0.70, respectively) on farms in the North East and South East of England. Separating lame sheep at pasture was associated with a decreased prevalence of all lameness and ID (PR = 0.75; PR = 0.73) and location of the farm in South East England was associated with a lower prevalence of all lameness and ID (PR = 0.75; PR = 0.71, respectively). We conclude that management factors associated with all lameness, and lameness attributed to ID and FR are similar

Recognition of lameness and decisions to catch for inspection among sheep farmers and specialists in GB

Background: Epidemiological studies have used farmer estimates of the prevalence of lameness in their flocks. This assumes that farmers can identify lame sheep. Eight movie clips of sheep with locomotion from sound to moderately lame were used to investigate the ability of farmers and sheep specialists to recognise lame sheep. Each participant was asked to complete a form and indicate, for each movie clip, whether they thought the sheep was lame and whether they would catch it if it was the only lame sheep or if 2 – 5, 6 – 10 or > 10 sheep were equally lame. The farmers' responses were compared with their estimates of flock lameness prevalence and the interval between observing a lame sheep and catching it. Results: 178 farmers and 54 sheep specialists participated. Participants could identify even mildly lame sheep but made a separate decision on whether to catch them. This decision was dependent on the severity of lameness and the number of sheep lame in a group. Those who said they would catch the first lame sheep in a group were significantly more likely to catch mildly lame sheep (farmer-reported median prevalence of lameness 5% (IQR: 2%–6%)). In contrast, farmers who waited for several sheep to be lame indicated that they would only catch more severely lame sheep (farmer reported median flock lameness 11% (IQR: 9%–15%)). Approximately 15% of farmers did not catch individual lame sheep (farmer reported median flock lameness 15% (IQR: 10%–15%)). The flock prevalence of lameness increased as time to treatment increased and time to treatment was positively correlated with only catching more severely lame sheep. Conclusion: If movie-clips are similar to the flock situation, farmers and specialists can recognise even mildly lame sheep but vary in their management from prompt treatment of the first lame sheep in a group to no individual sheep treatments. The former practices would be appropriate to minimise transmission of footrot, a common, infectious cause of lameness and so reduce its incidence. The analysis also suggests that farmers estimate lameness prevalence relatively accurately because farmers who treated the first mildly lame sheep in a group also reported the lowest prevalence of lameness in their flock

Epidemiological investigations into lameness in sheep

Lameness is the greatest health and welfare concern in sheep flocks in the U. K. This thesis presents research on epidemiology of lameness in sheep Most previous studies quantifying lameness and its causes are based on the premise that farmers can identify the causes of lameness and recognise lame versus sound sheep. In 2005, a postal questionnaire was sent to a random sample of English sheep farmers to investigate whether farmers could correctly name six common foot lesions in sheep (interdigital dermatitis (ID), footrot (FR), contagious ovine digital dermatitis (CODD), shelly hoof, foot abscess and toe granuloma) from a characteristic picture and a written description. The same questionnaire of six lesions was presented at a meeting of specialist sheep advisors, primarily veterinarians. Approximately 20% of farmers and 80% of sheep specialists named all 6 lesions correctly, indicating a gap in knowledge between sheep advisors and sheep farmers. In addition, farmers tended to name any hoof horn damage as footrot which might imply that some lame sheep receive incorrect treatment. Management factors associated with the prevalence of farmer estimated lameness (irrespective of farmer recognition of lesions) and the adjusted prevalence of lameness caused by ID and FR among flocks where farmers correctly recognised both lesions were investigated and compared in negative binomial regression models. Farmers who routinely foot trimmed and frequently footbathed their sheep reported a higher prevalence of lameness, ID and FR. Farmers who stocked their sheep at >8ewes/hectare reported a high prevalence of both lameness and ID whilst those who separated `some' or `all' lame sheep at pasture reported a low prevalence of both lameness and ID. Farmers in the east of England reported a lower prevalence of lameness, ID and FR compared with central England. A numerical rating locomotion scoring scale (0-6) was developed to monitor locomotion in sheep in a research setting. There was good agreement between and within trained observers using this scale. This scoring system was used in a longitudinal study on one farm, two groups of sheep (30 in each group) with different treatment regimes (antibiotic injection & antibiotic spray vs. foot trimming and antibiotic spray; and occasional footbathing) for lameness with FR and ID were followed for five weeks to investigate the temporal associations between ID, FR and the effect of different treatments on locomotion. From the examinations it was concluded that even mildly lame sheep can have FR and ID. In a multilevel linear mixed model, there was a significant association between ID, FR and locomotion score with the mean score of 0.25 increasing to 0.43 for sheep with ID and to 2.18 for sheep with FR. In addition, sheep that developed FR had a significantly raised locomotion score the week before FR became clinically apparent. Treatment with antibiotic injection and antibiotic spray significantly reduced the locomotion score of sheep the following week. The movie clips from the locomotion scoring reliability study were used to investigate farmer and sheep specialist recognition of lame sheep and decisions on whether to catch them. A group of farmers from three regions (Devon, Newark and Norfolk) and sheep specialists at a Sheep Veterinary Society meeting were shown eight movie clips of sheep with varying locomotion scores. Although the majority of farmers and sheep specialists identified mildly lame sheep with a locomotion score of 2, only 50% of them would catch such a sheep if it was the only lame sheep in the group. Most farmers and sheep specialists did not catch lame sheep until the lameness was locomotion score 3 or 4. The more frequently farmers caught lame sheep, and the milder the lameness when a decision to catch was taken, the lower the farmer reported prevalence of lameness in the flock. The research in this thesis suggests that farmers, who are the primary carers for lame sheep, do not always name foot lesions correctly and so sheep may receive inappropriate treatment for some lesions. In addition, whilst farmers and sheep specialists can recognise lame sheep, they do not always catch and treat mildly lame sheep. Farmers who caught all mildly lame sheep within a few days of seeing them lame reported a lower prevalence of lameness in their flock. This might be explained by the evidence from this thesis that mildly lame sheep can have FR or ID and so prompt treatment of these lame sheep reduces the prevalence and incidence of FR and ID

Technology adoption on farms: Using Normalisation Process Theory to understand sheep farmers’ attitudes and behaviours in relation to using precision technology in flock management

Evidence suggests that UK sheep farmers experience lower productivity and profit margins than other livestock sectors and that they do not necessarily know where they gain or lose income from their flocks. More efficient use of precision technology has been identified as a potential way of addressing this problem. The mandatory requirement for Electronic Identification (EID) tags to be placed on all sheep offers an opportunity for sheep farmers to adopt precision technologies to manage herd health and maximise production and profit. Although the charactistics of farmers that are associated with adoption or non adoption of technology have been identified little is known about the social processes, meanings and experiences that influence uptake. This paper is novel as it draws on data from 36 sheep farmers in the UK and applies Normalization Process Theory (NPT) to gain an understanding of the reasons they do or do not use EID related precision technology on their farms. The interviews were tape recorded, transcribed verbatim and analysed using NVivo. Although respondents acknowledged the potential value of precision technology to improve their farm businesses they appeared to have alternative beliefs that were counter productive. Their beliefs that using precision technology posed a threat to their role as a good stockman, that it could not replace the need for hands-on interaction with their animals and that it was costly and difficult to use created an implementation gap. The use of NPT as an evaluation framework provided a valuable tool for increasing the understanding of contextual characteristics that undermine the routine embedding of such technology by sheep farmers. The data suggests that normalisation of the use of precision technology amongst sheep farmers could potentially be increased if manufacturers/suppliers co-design and work with farmer’s to ensure that the technology enables the farmer to be in control and operates as an aid to achieving high quality stockmanship rather than a mechanism for profit maximisation

Environmental and field characteristics associated with lameness in sheep: a study using a smartphone lameness app for data recording

Background: Sheep lameness is a major concern among farmers and policymakers with significant impacts on animal welfare standards as well as financial and production performance. The present study attempts to identify the relative importance of environmental and farm-level management characteristics on sheep lameness.Method: To address this objective, data were derived from the SPiLaMM project from 18 farms that used smartphone app to collect data, the British Geological Survey and the Meteorological Office over 2016–2018. Data were analysed using a multilevel Poisson regression model.Results: Temperature and higher length of pasture had a positive relationship with lameness while concentration of Selenium in soil and flock size had a negative relationship with lameness. In addition, results showed lower lameness levels for the bedrock class mudstone, siltstone, limestone and sandstone in comparison to sandstone and finally, lambs and ewes younger than 1 year old had lower levels of lameness than older ewes.Conclusion: Findings of the present approach show the potential use of data collected via a smartphone app to study the epidemiology of disease. Furthermore, factors identified could be validated in intervention studies and generate data-driven disease predictive models

The inter- and intra-observer reliability of a locomotion scoring scale for sheep

A seven point locomotion scoring scale, ranging from 0 = normal locomotion to 6 = unable to stand or move, has been developed. To test the between and within observer reliability of the scale, 65 movie clips of sheep with normal and varying degrees of abnormal locomotion were made. Three observers familiar with sheep locomotion were trained to read the movie clips. Thirty clips were randomly selected and used to test between and within observer agreement. There was high inter-(intra-class correlation coefficient [ICC] = 0.93, weighted kappa [κw] = 0.93) and intra-(ICC = 0.90, κw = 0.91) observer reliability, with no evidence of observer bias. The main between score differences were for scores 0 (normal) and 1 (uneven posture and shortened stride but no head movement). The results indicate that the locomotion scoring scale using groups of defined observations for each point on the scale was reliable and may be a useful research tool to identify and monitor locomotion in individual sheep when used by trained observers

Evaluating observer agreement of scoring systems for foot integrity and footrot lesions in sheep

Background: A scoring scale with five ordinal categories is used for visual diagnosis of footrot in sheep and to study its epidemiology and control. More recently a 4 point ordinal scale has been used by researchers to score foot integrity (wall and sole horn damage) in sheep. There is no information on observer agreement using either of these scales. Observer agreement for ordinal scores is usually estimated by single measure values such as weighted kappa or Kendall’s coefficient of concordance which provide no information where the disagreement lies. Modeling techniques such as latent class models provide information on both observer bias and whether observers have different thresholds at which they change the score given. In this paper we use weighted kappa and located latent class modeling to explore observer agreement when scoring footrot lesions (using photographs and videos) and foot integrity (using post mortem specimens) in sheep. We used 3 observers and 80 photographs and videos and 80 feet respectively. Results: Both footrot and foot integrity scoring scales were more consistent within observers than between. The weighted kappa values between observers for both footrot and integrity scoring scales ranged from moderate to substantial. There was disagreement between observers with both observer bias and different thresholds between score values. The between observer thresholds were different for scores 1 and 2 for footrot (using photographs and videos) and for all scores for integrity (both walls and soles). The within observer agreement was higher with weighted kappa values ranging from substantial to almost perfect. Within observer thresholds were also more consistent than between observer thresholds. Scoring using photographs was less variable than scoring using video clips or feet. Conclusions: Latent class modeling is a useful method for exploring components of disagreement within and between observers and this information could be used when developing a scoring system to improve reliability

Associations between sheep farmer attitudes, beliefs, emotions and personality, and their barriers to uptake of best practice: the example of footrot

There is interest in understanding how farmers’ behaviour influences their management of livestock. We extend the theory of planned behaviour with farmers attitudes, beliefs, emotions and personality to investigate how these are associated with management of livestock disease using the example of footrot (FR) in sheep. In May 2013 a one-year retrospective questionnaire was sent to 4000 sheep farmers in England, requesting data on lameness prevalence, management of footrot, farm/flock descriptors, and farmer-orientated themes: barriers to treating footrot, opinions and knowledge of footrot, relating to other people and personality. Principal component analysis (PCA) was used to make composite variables from explanatory variables and latent class (LC) analysis was used to subgroup farmers, based on nine managements of FR. Associations between LC and composite variables were investigated using multinomial logistic regression. Negative binomial regression was used to investigate associations between the proportion of lame sheep and composite and personality variables. The useable response rate was 32% and 97% of farmers reported having lame sheep; the geometric mean prevalence of lameness (GMPL) was 3.7% (95% CI 3.51%–3.86%). Participants grouped into three latent classes; LC1 (best practice—treat FR within 3 days of sheep becoming lame; use injectable and topical antibiotics; avoid foot trimming), 11% farmers), LC2 (slow to act, 57%) and LC3 (slow to act, delayed culling, 32%), with GMPL 2.95%, 3.60% and 4.10% respectively. Farmers who reported the production cycle as a barrier to treating sheep with FR were more likely to be in LC2 (RRR 1.36) than LC1. Negative emotions towards FR were associated with higher risk of being in LC2 (RRR 1.39) than LC1. Knowledge of preventing FR spread was associated with a lower risk of being in LC2 (RRR 0.46) or LC3 (RRR 0.34) than LC1. Knowledge about FR transmission was associated with a lower risk of being in LC3 (RRR 0.64) than LC1. An increased risk of lameness was associated with the production cycle being a barrier to treating sheep with FR (IRR 1.13), negative emotions towards FR (IRR 1.13) and feelings of hopelessness towards FR (IRR 1.20). Conscientiousness (IRR 0.95) and understanding the importance of active control of lameness (IRR 0.76) were associated with reduced risk of lameness. We conclude that emotions and personality are associated with differences in farmer management of FR and prevalence of lameness. Further understanding how personality and emotions influence change in behaviour is key to increasing uptake of new information

Influencing Change: When “Best Practice” Changes and the Prototypical Good Farmer Turns Bad

Twenty-nine farmers with a flock prevalence of lameness >5% were visited in 2013. They participated in a facilitated discussion on treatment of footrot, and evidence-based new “best practice.” One year later, farmers were revisited and management and motivators for change were discussed. Farmers were asked how they would persuade other farmers to adopt “best practice.” Initially, most participants were resigned to having lame sheep. They believed that prototypical “good farmers” (including trusted family) practiced foot trimming, the traditional “best practice” and that the new “best practice” would be expensive and time consuming. Between 2013 and 2014 lameness prevalence reduced from 7.6 to 4.3%. The major behavioral changes were reduction in foot trimming, increased use of antibacterials to treat footrot, and treating sheep within a week of becoming lame. In 2014, participants were re-interviewed. They reported that an increased knowledge of the evidence-base, trust in the facilitator and talking to other trusted farmers who had already adopted the new “best practice” overcame concerns about the prototypical “good farmer” and motivated change. Persistent change occurred because participants observed health benefits for their sheep and that the new “best practice” had saved time and money. Participants stated that other farmers would be convinced to change to the new “best practice” because it saved time and money, ironically, these were among the original barriers to change. This is possibly an example of cognitive dissonance because farmers had become positive about the benefits of saving time and money following a change in their own behaviors