Background: Youngstock are susceptible to parasitic disease; the development of anthelmintic resistance is increasing. Objectives: Investigate stud owners’/managers’ perceptions of prevalence of parasite-associated diseases and current management approaches to control parasites on UK studs. Study Design: Cross-sectional study; on-line survey. Methods: SurveyMonkey questionnaires (multiple choice, Likert scale and free text questions) distributed via practices, press, social media and snowball sampling. Descriptive and inferential statistics performed in Microsoft Excel and STATA. Statistical differences assessed with Fisher’s exact test or Mann Whitney U test. Results: 56 usable responses. The median number of foals born per farm per year was 9, and the median number of resident mares/permanent boarders was 14. Predominant breeds were Thoroughbreds and Warmbloods. Perceived parasite-associated illness in the past year was reported by 35.7% respondents (weight loss (65.0%), diarrhoea (40.0%) and colic (15.0%)) with young adults (1-3 years) most affected (47.7%), followed by adults (31.8%), weanlings (27.3%) and foals (20.5%). New mares weren’t turned out until they were administered an anthelmintic in 53.6%, whilst 41.1% performed faecal egg counts and treated if necessary, and 16.1% turned mares out without treating or testing. The median stocking density was 0.3 mares / acre (significantly lower for Thoroughbreds than Warmbloods / “others” (p<0.01)). 32.1% of farms never “poo picked” pastures; 89.3% harrowed paddocks; and 57.1% co-grazed horses with ruminants. Main Limitations: Small sample size. Potential selection bias and response bias. Conclusions: Parasite-associated diseases on stud farms are common. Many farms fail to implement management practices (eg poo-picking, co-grazing with ruminants) that could reduce the risk of parasite transmission on the premises. Harrowing paddocks could increase the risks of parasite transmission. Results identify areas where management practices should be improved.

Background : Anthelmintic resistance in equine parasites is increasing. Frequent anthelmintic use accelerates selection for resistance. Objectives : Investigate how horse owners currently use anthelmintics to control intestinal parasites. Study design : Online survey. Methods: Questionnaire distributed via practices, equestrian organisations, etc., December 2021 to October 2022. Combination of multiple choice, Likert scale and free text questions. Descriptive / inferential statistics performed (Microsoft Excel and IBM SPSS). Results : 4232 useable responses. Owners of horses on livery yards less likely to make worming decisions compared to those on private properties (p<0.001); managers made decisions in 39.6% of horses on livery yards; 60.7% of owners sought worming advice from their veterinarian; 52.0% administered anthelmintics based on routine faecal egg counts (FECs) / tapeworm serology result; 30.0% routinely tested, but wormed at least once a year regardless of the results; 16.1% did not test, but wormed at least once a year. Owners were more likely to administer anthelmintics based on test results if they sought veterinary advice or were on a health programme (both p<0.001). Of those who routinely wormed, 54.9% wormed once a year; 45.1% wormed twice or more a year. Frequency of routine worming was higher if they didn’t routinely test (p<0.001); 88.9% simultaneously wormed all horses on the pasture. Moxidectin was the first choice for 82.2% of owners who routinely wormed at least once yearly. Routine FECs were performed by 84.7%, higher for those who sought veterinary advice (89.3%, p<0.001). Tapeworm ELISAs were utilised by 40.8%, higher for those on a health programme (68.1%; p<0.001); 58.5% routinely treated for tapeworms regardless of test results. Main Limitations : Selection bias. Conclusions : Owners apply moderately good diagnostic-led parasite control practices, but still common to regularly treat with anthelmintics (30.0% worming at least once a year regardless of the FEC results).

Background : Anthelmintic resistance in equine parasites is increasing. Pasture management is a vital component of parasite control, and is important to limit the development of resistance. Objectives : Investigate how horse owners use management procedures to control common intestinal parasites in horses. Study design : Online survey. Methods : Questionnaire distributed via practices, equestrian organisations, etc., December 2021 - October 2022. Combination of multiple choice, Likert scale and free text questions. Descriptive and inferential statistics performed in Microsoft Excel and IBM SPSS. Results : 4232 useable responses from the UK, predominantly England (85.4%). Premises included livery yards (45.7%) and private properties (51.1%). Most horses (70.4%) were aged 6-20 years. Over half (55.9%) were used for general riding/pleasure; 58.9% grazed with 1-3 other horses, while 20.7% grazed alone; 21.5% alternated or co-grazed with ruminants (significantly higher for horses grazing on private properties compared to horses grazing on livery yards; 73.3% of owners removed faeces from pastures (poo-picking), of which 86.4% removed faeces twice a week or more. Owners of horses pastured individually were significantly more likely to poo-pick (89.8%) than horses pastured in groups (68.9%); 77.1% of respondents rested pastures, but less than 5% for over 6 months. Only 5.1% of owners reported they had experienced illnesses related to worms in any horse (commonest clinical signs were colic and weight loss). Limitations : Selection bias. Conclusions : Results suggest a lack of understanding of the principles of non-chemical parasite control among many horse owners. Many owners (>25%) are not routinely poo-picking. Horses pastured alone or kept on a private property were significantly more likely to have their faeces regularly removed than thoses pastured in groups or kept on livery yards.