Identifying veterinary surgeons' barriers to, and potential solutions for, improving antimicrobial stewardship among sheep farmers in Northern Ireland.

Background: In order to improve antimicrobial stewardship (AMS), including changes in antimicrobial prescribing and use, an enhanced understanding is needed of the barriers that veterinary surgeons (vets) encounter to institute such change. Methods: A qualitative approach, using grounded theory, was followed. Interviews and discussion groups, with vets and farm industry stakeholders in Northern Ireland (NI), were undertaken to identify and explore attitudes and behaviours surrounding AMS, with a particular emphasis on the barriers vets encountered and the context within which they were working. Results: Seven inter-related themes associated with improving AMS among their sheep farming clients were identified. The first six addressed barriers were working under commercial and practical constraints, farmer behaviour, multiple medicine sources, poor prescribing practice, a perceived lack of incentive or facilitation to improve AMS and a perceived lack of action by regulators to challenge poor AMS. The seventh theme revealed suggestions vets considered that may improve AMS in NI, including greater state intervention in recording and regulating medicine sales. Conclusions: Improving AMS will require vets and their client farmers to change behaviour. This will involve concerted effort over an extended period of time to enact and embed change. Veterinary surgeons believe that further action by the industry and state to develop centralised antimicrobial sales recording and by the state to enforce prescribing regulations will aid their efforts. However, critical to achieving this is the development of a sustainable and funded mechanism to create more meaningful farmer-vet consultation around flock health prior to every prescription to improve AMS and sheep welfare.

Antibiotic use in the Northern Irish sheep flock: What lessons can be learnt from medicine records and farmer attitudes to improve stewardship of these essential medicines?

Stewardship of antibiotics used in livestock production has come under increasing scrutiny, from both the animal welfare point of view and due to concerns that antibiotic use in livestock may pose a risk to human health through selection pressure to drive development of antibiotic resistant strains of bacteria. Despite this concern, however, antibiotic consumption in the sheep sector is currently poorly described. This study determines the range and quantities of antibiotics used in the Northern Irish (NI) sheep flock as well as exploring drivers for their use. A mixed-methods approach was utilised, with an anonymous online scoping survey, analysis of the medicine records from 52 NI sheep farms and semi-structured interviews undertaken with 27 farmers. Eighteen farmers contributed both records and participated in interviews. Veterinary medicine records were derived from two sources: on-farm medicine books (seven) or veterinary practice sales data (51). As six of these farmers provided information from both sources a total of 52 unique farms participated. Overall, antibiotic use in sheep on the 52 farms sampled was low, with a median value of 11.35 mgPCU-1 (mean 13.63 mgPCU-1, sd 10.7; range 0-45.29 mgPCU-1), with all farms below 50 mgkg-1. Critically important antibiotics accounted for 0.21% of all antibiotics purchased. Lameness was the main driver of antibiotic use identified by this study. Others included a range of prophylactic treatments such as oral antibiotics to prevent watery mouth, injectable antibiotics to prevent abortion and following assisted lambing. Farmers acknowledged some of these uses had become habitual over time. The veterinary medicine sales records demonstrated significant sales of antibiotics not authorised for use in sheep, on an ongoing, rather than case-by-case, basis. Farmers were positive about their veterinarian's ability and knowledge to improve flock welfare and productivity, but were unwilling to pay for this advice. However, veterinarians may have facilitated weak medicine stewardship through a failure to adequately challenge farmers seeking antibiotics. Farmers did not maintain accurate or up-to-date on farm medicine or production records in the majority of cases. Despite this lack of on-farm recording, veterinary sales records can be studied in consultation with farmers to provide veterinarians with a farm-specific insight into antibiotic use and related attitudes and behaviours. Farmers and veterinarians can then identify areas and behaviours to target collaboratively, improving antibiotic and wider medicine stewardship, whilst simultaneously improving flock health and productivity.

Improving analgesia provision for sheep: An analysis of farm medicine records and attitudes towards pain relief on sheep farms in Northern Ireland.

Background: Management of pain is critical to improve the welfare of farmed livestock and meet consumer expectations. There is limited published information about the use of analgesic drugs in the sheep sector. Methods: A mixed-method approach was followed. The range of analgesic drugs used on 52 Northern Irish sheep farms was determined through analysis of medicine purchase records. Through interview and discussion groups, with both farmer and veterinarian participants, attitudes towards the use and adoption of such medicines were explored. Results: The use of non-steroidal anti-inflammatory drugs (NSAIDs) was widespread and highly variable. One-third of farmers in the sample did not purchase any NSAID. Meloxicam was the most commonly purchased NSAID by mass (72%) and standardised dose (73%). During interviews and discussions, farmers outlined the benefits they saw in using NSAIDs and how veterinarians influenced their uptake of these medicines. Use of corticosteroid was evidenced on 50% of the farms that supplied medicine records for analysis. Conclusions: Veterinarians can influence farmers to adopt NSAIDs for the provision of analgesia in their sheep and farmers observed the benefits they delivered. However, many farmers are still to be reached with this message, perhaps due to being largely self-sufficient and rarely engaging with veterinarians. Veterinarians have the opportunity to challenge farmers about the provision of analgesia, especially when farmers seek antibiotics for painful conditions such as lameness. Currently, the lack of an authorised product in the UK, with associated treatment guidance and industry promotion, may limit veterinarians' confidence in prescribing drugs for pain control in sheep.

Onchocerca Cervicalis: A Survey into Awareness and Knowledge of The Parasite Amongst UK Equine Veterinarians.

The nematode Onchocerca cervicalis is the most common causative agent of equine onchocerciasis; this condition is characterised by pruritus and dermatitis and is a differential diagnosis for insect bite hypersensitivity. Onchocerciasis is currently presumed of minor importance within the UK, however prevalence may increase if macrocyclic lactone use declines amid concerns about anthelmintic resistance in gastrointestinal nematodes. This survey aimed to establish O. cervicalis awareness and knowledge levels amongst UK equine veterinarians and to determine approximate numbers of UK horses affected with unresponsive cases of dermatoses, including insect bite hypersensitivity. An online survey was distributed to UK equine vets between December 2019 and February 2020. Of 88 respondents, 78% were aware of O. cervicalis, however 49% of these answered less than half the questions presented about the parasite's lifecycle correctly. Approximately 25% of insect bite hypersensitivity cases respondents saw were deemed unresponsive to standard treatments, 84% of respondents had not previously considered onchocerciasis as a differential diagnosis in such cases. Findings suggest knowledge of O. cervicalis amongst UK equine vets is lacking, highlighting a need to raise awareness and consideration of the parasite as a differential when investigating equine dermatoses.

New Insight into the Prevalence and Risk Factors for Three Distinct Hoof Conformation Traits in UK Commercial Sheep Flocks.

Lameness in sheep continues to be a global health, welfare and economic concern. Damaged, misshapen or overgrown feet have the potential to cause lameness either directly, or indirectly. There is a lack of understanding of the predisposing factors for different hoof conformation traits in sheep. Our exploratory study aimed to investigate the prevalence of, and risk factors for, three distinct hoof conformation traits relating to the sole and heel, hoof wall, and hoof wall overgrowth. Feet of 400 ewes from four UK commercial sheep farms were inspected at four time points across 12 months. For each conformation trait, a four-point ordinal system was used to score each individual claw, and foot-level scores were calculated. We present 92.4% of foot-level observations to be affected by ≥1 conformation traits. Whilst hoof conformation traits were correlated to some degree, a unique set of sheep-, foot- and farm-level factors were associated with each distinct conformation trait. We provide, for the first time, key insight into the multifaceted and multifactorial aetiology of hoof conformation in sheep, building upon previous landmark studies. Our results inform hypotheses for future prospective studies investigating the risk factors for adverse hoof conformation in sheep.

Prevalence and Temporal Dynamics of White Line Disease in Sheep: An Exploratory Investigation into Disease Distribution and Associated Risk Factors.

Lameness in sheep is a global health, welfare and economic concern. White line disease (WLD), also known as shelly hoof, is a prevalent, non-infectious cause of lameness, characterised by the breakdown of the white line. Little is known about the predisposing factors, nor the individual disease dynamics over time. Our exploratory study aimed to investigate the prevalence and temporal dynamics of WLD, and the associated risk factors. Feet of 400 ewes from four UK commercial sheep farms were inspected for WLD at four time points across 12 months. The change in WLD state at foot-level (develop or recover) was calculated for three transition periods. We present WLD to be widespread, affecting 46.8% of foot-level and 76.6% of sheep-level observations. States in WLD changed over time, with feet readily developing and recovering from WLD within the study period. The presence of WLD at foot-level, the number of feet affected at sheep-level and dynamics in development and recovery were driven by a variety of foot-, sheep- and farm-level factors. We provide key insight into the multifaceted aetiology of WLD and corroborate previous studies demonstrating its multifactorial nature. Our study highlights an opportunity to reduce WLD prevalence and informs hypotheses for future prospective studies.

Characterisation of Dichelobacter nodosus on Misshapen and Damaged Ovine Feet: A Longitudinal Study of Four UK Sheep Flocks.

Dichelobacter nodosus is the causal agent of ovine footrot, a contagious disease of welfare and economic concern worldwide. Damaged feet may be subclinical carriers of D. nodosus and covertly spread infection. Accordingly, we evaluated the risk of misshapen and damaged feet on D. nodosus presence and load in four commercial UK sheep flocks. Foot-level observations and swabs (n = 972) were collected from ewes (n = 85) over 12 months. On average, ewes were sampled three times. Feet were inspected for disease and scored (good/poor) for three hoof conformation traits (sole and heel, wall, and wall overgrowth). Swabs were analysed for presence and load of D. nodosus, and mixed models were constructed. Poor hoof conformation traits were present in 92.5% of foot-level observations. Feet with poor sole and heel conformation were more likely to have higher D. nodosus loads (ß = 0.19, 95% CI: 0.04-0.35) than those with good conformation. Furthermore, on feet positive for D. nodosus, wall overgrowth was associated with higher D. nodosus loads (ß = 0.27, 95% CI: 0.01-0.52). Feet with aspects of poor conformation covertly harbour D. nodosus and are a source of infection. Flock management should be guided by hoof conformation to reduce disease challenge.