Exploiting Scanning Surveillance Data to Inform Future Strategies for the Control of Endemic Diseases: The Example of Sheep Scab

"Nobody here is an individual": Developing a place-based understanding of biosecurity for managing sheep scab on the Western Isles of Scotland

Sheep scab causes economic losses and animal welfare problems and has proven difficult to control in the UK. Research has highlighted the importance of developing place-based approaches to understanding and controlling sheep scab. This paper builds on this literature through introducing the concept of marginality in the case study of managing sheep scab on the island of Lewis and Harris in the Scottish Western Isles. The paper also proposes steps for developing a place-based understanding of biosecurity. The research draws on interviews and workshops with crofters analysed using thematic analysis. Crofting is a unique system of land management particular to Scotland. Crofters have the right to manage a small area of private land and access to a larger area of common grazing. The research found that there was a tension between the cultural heritage and social benefits of traditional crofting practices of common grazing and communal husbandry of sheep and the biosecurity imperative to reduce the mixing of sheep to prevent the spread of disease. Dynamics of marginalisation were also disrupting established husbandry practices through a lack of people and loss of sheep from the land. The crofters also identified collective actions they could take to tackle sheep scab, including collective dipping and controlling the movement of animals onto the island. Previous research has shown that in marginalised areas, social capital: networks between people, are not a panacea for bringing about positive change and additional resources from outside may be needed. Based on the findings of this research we suggest three phases for developing a place-based conception of biosecurity for livestock keepers. The first phase is to understand both the biosecurity challenges facing communities and cultural and social aspects of farming systems that are important to a region. The second is to facilitate livestock keepers to co-produce their own priorities for biosecurity that allow them to address disease management challenges in their own constraints. The third phase is to enable communities to implement measures in their context. This can involve facilitating access to potential financial resources, equipment, expertise and links with other community groups. These phases will facilitate them in developing their definition of place-based biosecurity. This paper addresses the first and preliminary research on the second stages of this process. Further research will lead to actions on the third phase to help crofters in Lewis and Harris to put a place based communal understanding of biosecurity into practice.

The tales of contradiction: A thematic analysis of British sheep farmers' perceptions of managing sheep scab in their flocks

Sheep scab is endemic in Great Britain with an estimated national herd-level prevalence of 10.9% from a surveyed population of sheep farms. Previous studies have investigated how sheep farmers manage sheep scab on their farms in Great Britain, but there have not been any qualitative studies investigating sheep farmers perceptions on the roles different stakeholders have in the management of sheep scab. This qualitative study aims to explore how sheep farmers perceive their role and the different stakeholders' roles in the management of sheep scab, and how they would like sheep scab to be managed going forward. Semi-structured interviews were conducted with 43 sheep farmers from England, Scotland, and Wales. The data were analysed using reflexive thematic analysis, through the theoretical lens of Foucault's notion of 'biopower'. Two themes were generated: 'The feeling of powerlessness leads to a need of rules and regulations', with sub-themes: 'The need for governmental rules and regulations' and 'The need for rules and regulation at livestock markets', and 'An apparent lack of sheep scab surveillance', with sub-themes: 'The farmers perceive that the veterinarians have control over surveillance' and 'The farmers have control over surveillance on their farms'. In the first theme, the respondents suggested that more rules and regulations to control the management of sheep scab was required. This included reinstating of sheep scab as a notifiable disease in England and Wales, as well as more regulations at livestock markets to prevent the trading of infested sheep; both of which would subject the farmers to regulatory power mechanisms. The second theme centred around who has the control of surveillance on the farms. Most of the respondents perceived that the veterinarians had knowledge and expertise of the local area on sheep scab, which they were able to relay to the farmers. Thus, veterinarians exerted disciplinary power by creating 'docile' bodies. However, it also appeared that veterinarians were not regularly called onto farms. Although disciplinary power flows through the interactions between the farmer and veterinarian, the techniques currently used are not always having their desired effect. The study demonstrated that how sheep farmers want sheep scab to be managed is, at times, conflicting and contradictory, which highlights the complexity of sheep scab as a disease to manage.

Assessment of knowledge, attitudes, and practices related to the prevalence of sheep scab among communal sheep farmers in Eastern Cape Province, South Africa

Background and Aim

Sheep scab is one of the most contagious diseases of sheep found in rural communities worldwide and is a major health and welfare concern for sheep farming. Information on the attitudes of communal farmers to sheep scab remains speculative in the Eastern Cape Province. This study aimed to investigate knowledge, attitudes, and practices related to the prevalence of sheep scab among communal sheep farmers in Eastern Cape Province, South Africa.

Materials and Methods

From June to August 2022, a cross-sectional survey using a semi-structured questionnaire (n = 160) was conducted in two rural communities of the Enoch Mgijima Local Municipality in Eastern Cape Province. Purpose sampling was used to obtain respondents' knowledge, attitudes, and management practices regarding sheep scabs.

Results

Among respondents, 81% were males and 19% were females. The majority of sheep farmers (59%) in both communities were aware of sheep scabs, but the majority (64%) did not receive any farming training. The majority of sheep farmers (65%) believed that sheep scab was the most serious threat to their sheep production since it increased mortality. In the past 3 years, approximately 57% of respondents reported an increase in the prevalence of sheep scab. The majority of farmers reported wool loss as the most noticeable clinical symptom (73%). More than 80% of sheep farmers do not use acaricide on a regular basis. Sixty-one percent of farmers prefer a pour-on topical application method. The frequency of annual dipping was every fortnight (40%), during summer and winter (24%). Most farmers (66%) regularly vaccinate their sheep.

Conclusion

The prevalence of sheep scab is increasing in these communities; however, a better understanding of the factors that facilitate its transmission is required to allow improved management and control of this disease. The government must involve extension officers and distribute them to disseminate information to farmers. Thus, it will be easy to translate the literature into action.

Treatment of sheep prior to movement: its contribution to an effective scab (psoroptic mange) management strategy

BACKGROUND

Ovine psoroptic mange (sheep scab) is an important disease of sheep worldwide caused by the parasitic mite, Psoroptes ovis. It has a negative impact on animal welfare and leads to significant economic losses for the sheep industry. Effective and targeted management is required to limit its transmission.

METHODS

A stochastic metapopulation model of sheep scab transmission is used to investigate the contribution of the treatment of sheep prior to movements to sales, gatherings (predominantly markets) and away grazing to the reduction of prevalence of farms with scab in Great Britain.

RESULTS

Treatment prior to movement to gatherings resulted in an 86% reduction in the overall prevalence of farms with scab and was more effective at reducing the overall prevalence of farms with scab than treatment before other categories of movements. The relative risk of farms having scab infection was inversely related to the percentage of farms which treated, but this relationship was not linear, with the biggest declines in the prevalence of farms with scab being achieved by small percentages of farms treating; a 50% relative reduction in the farm prevalence was achieved with only 15% of farms treating prior to gathering movements.

CONCLUSIONS

The results suggest that pre-movement treatment of sheep could make an important contribution to national scab control and, in practice, the approach could be more highly targeted if used in conjunction with known geographic and management risk factors for scab.

Evaluation of the Role of Veterinarians for Outcomes Related to the Health and Production of Dairy Small Ruminants in Greece

The objective of the present study was to evaluate the potential benefits of veterinarians in improving the health and welfare of dairy sheep and goats by studying the associations of management practices employed in the farms with production- or health-related outcomes in sheep and goat farms in Greece. This work explored associations with 'professional relationship with a veterinarian' at 444 small ruminant dairy farms in an investigation performed around Greece, where 106 variables, related to infrastructure, animals, production outcomes, health management, health problems and human resources, were assessed. In 384 (86.5%) farms, a professional relationship with a veterinarian was maintained. The median value of visits made annually by veterinarians to these farms was five. In farms with a professional relationship with a veterinarian, significant differences were found in 24 variables (35.8%) related to management practices and 6 (30.0%) production- or health-related outcomes. In multivariable analysis, the following emerged with a significant association: epg counts in faecal samples (p = 0.014), average annual milk production per ewe/doe (p = 0.015), somatic cell counts in bulk-tank milk (p = 0.037), and annual incidence of clinical mastitis (p = 0.044). Moreover, associations of the characteristics of veterinarians emerged with somatic cell counts in bulk-tank milk: the gender (p < 0.0001) and the age (p = 0.004) of the veterinarians. The results attest that the application of veterinary advice and clinical services in sheep and goat dairy farms contributes to the improved health, production and welfare of animals.

A survey of British sheep farmers: Practices, opinions and knowledge surrounding the management of sheep scab

Ovine psoroptic mange (commonly known as sheep scab) is, arguably, one of the most important ectoparasitic diseases of sheep in the UK. Although research has been conducted on the practices and knowledge of British sheep farmers regarding the management of sheep scab, recent data is limited. During October 2021 an online survey was completed by 725 British sheep farmers. Most respondents farmed in England (63.0%, 457/725), followed by Wales (20.6%, 149/725) and Scotland (16.4%, 119/725). Over half (53.0%, 384/725) of the respondents had experienced sheep scab in their flocks before, and 38.3% (147/384) of respondents experienced sheep scab twice or more in the previous ten years. The estimated prevalence of sheep scab from these surveyed farmers was 10.9% (79/725). Of the farmers who had experienced sheep scab before, only 36.2% (139/384) reported using skin scrapes and 12.5% (48/384) reported using blood tests for diagnosis. Over three-quarters of farmers quarantined all new sheep (76.6%; 498/650), but fewer quarantined returning sheep (28.6%; 83/290). Many of the respondents (43.7%, 252/577) did not quarantine new sheep for the suggested minimum 21 days. In addition, only 53.0% (384/725) of respondents answered all three of the knowledge questions regarding sheep scab correctly. The analysis illustrates that there is scope to improve the use of diagnostics, which suggests that misdiagnosis of sheep scab may be high and thus inappropriate treatments may be used, or treatments may not be used at all. It also demonstrated that there is scope for improvement in farmers' knowledge regarding sheep scab, particularly that sheep scab could be detected via a blood test and that the disease could present without visible signs. Our results further support that sheep scab is a large-scale endemic issue, potentially with an increasing prevalence in Great Britain. Future control interventions need to focus on improving knowledge exchange, raising awareness of best practice controls to ensure that better management strategies are employed by farmers, including improved control at livestock markets to reduce the national transmission and thus focus on coordinated control interventions.

Parasiticides: Weapons for Controlling Microbial Vector-Borne Diseases in Veterinary Medicine; The Potential of Ethnobotanic/Phytoparasiticides: An Asset to One Health

Some ectoparasites are vectors of illness-causing bacteria and viruses, and these are treated with antibiotic and antiviral drugs, which eventually contribute to the excessive use of antimicrobials. Therefore, the control of ectoparasites is crucial, and the challenge will be to manage them in a sustainable way. Data from a preliminary ethnobotanical survey was reanalyzed to obtain information on the use of various plant species in companion animals and livestock as ectoparasiticides. The survey responses were reviewed for traditional use of plants as ectoparasiticides, and cross-sectional bibliographic research was undertaken. The following plants were selected among the nine mentioned plants: Juglans regia, Daphne gnidium and Ruta graveolens, which have the most potential to be developed as veterinary ectoparasiticides. Moreover, the absence of published data for Plantago lanceolata and Cistus populifolius suggests that their traditional use as ectoparasiticides is noted here for the first time. In summary, these plants could give promising plant-derived veterinary ectoparasiticides that, ultimately, will help reduce and even avoid the excessive use of antimicrobials.