A questionnaire study on parasite control practices on UK breeding Thoroughbred studs.

Moredun Research Institute, Pentlands Science Park, Midlothian, EP26 0PZ, UK.
Equine Veterinary Journal (Impact Factor: 2.29). 11/2011; 44(4):466-71. DOI: 10.1111/j.2042-3306.2011.00493.x
Source: PubMed

ABSTRACT Improved education of veterinarians and equine owners/managers is essential in implementing parasite control strategies that are less reliant on chemicals.
This questionnaire study, conducted on 61 UK Thoroughbred (TB) establishments during 2009 and 2010, was designed to obtain an understanding of current helminth control practices on studs. To our knowledge, this is the first occasion that statements obtained from TB studs via questionnaire have been supported by statistical analysis.
Despite many respondents indicating high levels of concern regarding anthelmintic resistance, 56% of these establishments that received visiting equines co-grazed these animals with permanent stock and <74% administered anthelmintics prior to integration. In the 12 months preceding the study, most respondents administered frequent macrocyclic lactone (ML) treatments, with none appearing to leave any animals in groups untreated at each administration. Indiscriminate whole group treatments with MLs and movement of animals to 'clean grazing' post treatment (reported by >25% of respondents), indicates that many stud owners/managers are not aware of the strong risk factors for the development of anthelmintic resistance. Few studs had conducted faecal egg count (FEC) analysis in the past and only 22% indicated that they considered this form of analysis beneficial in determining anthelmintic choice.
The challenge now is to convince stud owners/managers to deviate from their current practices to control strategies that are more likely to preserve anthelmintic efficacy. Veterinarians need to get more involved in implementing these control strategies, with better emphasis placed on the role of diagnostic tests in facilitating targeted treatments and in investigating anthelmintic sensitivity in the associated nematode populations.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Since the 1960s equine parasite control has relied heavily on frequent anthelmintic treatments often applied with frequent intervals year-round. However, increasing levels of anthelmintic resistance in cyathostomins and Parascaris equorum are now forcing the equine industry to change to a more surveillance-based treatment approach to facilitate a reduction in treatment intensity. The principle of selective therapy has been implemented with success in small ruminant parasite control, and has also found use in horse populations. Typically, egg counts are performed from all individuals in the population, and those exceeding a predetermined cutoff threshold are treated. Several studies document the applicability of this method in populations of adult horses, where the overall cyathostomin egg shedding can be controlled by only treating about half the horses. However, selective therapy has not been evaluated in foals and young horses, and it remains unknown whether the principle is adequate to also provide control over other important parasites such as tapeworms, ascarids, and large strongyles. One recent study associated selective therapy with increased occurrence of Strongylus vulgaris. Studies are needed to evaluate potential health risks associated with selective therapy, and to assess to which extent development of anthelmintic resistance can be delayed with this approach. The choice of strongyle egg count cutoff value for anthelmintic treatment is currently based more on tradition than science, and a recent publication illustrated that apparently healthy horses with egg counts below 100 eggs per gram (EPG) can harbor cyathostomin burdens in the range of 100,000 luminal worms. It remains unknown whether leaving such horses untreated constitutes a potential threat to equine health. The concept of selective therapy has merit for equine strongyle control, but several questions remain as it has not been fully scientifically evaluated. There is a great need for new and improved methods for diagnosis and surveillance to supplement or replace the fecal egg counts, and equine health parameters need to be included in studies evaluating any parasite control program.
    Veterinary Parasitology 05/2014; 202(3-4):95-103. · 2.38 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Reasons for performing studyTraditionally, equine parasite control has relied heavily on frequent routine anthelmintic treatments applied with regular intervals year-round. However, current recommendations aim at employing a more surveillance-based approach. It remains unknown to which extent these recommendations are being implemented on US horse farms.Objectives To describe equine parasite control on Kentucky Thoroughbred farms and evaluate respondents’ willingness to pay for various attributes of surveillance-based parasite control strategies.Study designQuestionnaire survey performed among the membership of the Kentucky Thoroughbred Farm Managers’ Club.Methods The survey collected demographic data and information about current parasite control strategies. Further, respondents were asked to choose between hypothetical parasite control strategies described with a combination of different attributes: costs, time efforts needed, hypothetical disease risk levels, and hypothetical risks of anthelmintic resistance. Data were analysed with multivariable logistic analysis.ResultsAbout 26% responded to the survey (N = 112). Most respondents were concerned about anthelmintic resistance and incorporated veterinary advice in defining their deworming program. However, almost 70% were following a traditional rotational deworming program with little or no faecal surveillance. Respondents were willing to pay a premium for a product for which there is no known anthelmintic resistance and provided the highest possible decrease in health risks. The number of young horses on the farm, utilisation of veterinarian advice in developing a deworming program, concern about drug resistance in parasites, and having documented drug resistance on the farm all associated significantly with the type of parasite control program used.Conclusions Traditional approaches for equine parasite control are still widely used in the Kentucky Thoroughbred industry. The data suggest that respondents were only willing to make these changes if they could be provided assurance that the surveillance-based approach would prevent anthelmintic resistance and decrease health risks significantly for the horses.
    Equine Veterinary Journal 09/2014; · 2.29 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The current guideline was written to aid in the design, implementation and interpretation of studies for the assessment of drug efficacy against non-coccidial gastrointestinal protozoan parasites, with Giardia spp. as the leading example. The information provided in this guideline deals with aspects of how to conduct controlled studies using experimental infection models (dose determination and dose confirmation) and efficacy studies in commercial facilities (field effectiveness studies). Furthermore, the selection of suitable animals, housing, infection procedure, choice of diagnostic technique and data analysis are discussed. This guideline is intended to assist investigators in conducting specific studies, to provide specific information for registration authorities involved in the decision-making process, to assist in the approval and registration of new drugs and to facilitate the worldwide adoption of uniform procedures. The primary parameter for drug efficacy is the reduction in either parasite excretion or parasite counts and a minimum efficacy of 90% is required against non-coccidial gastrointestinal protozoa. A supporting efficacy parameter is a significant difference in the proportion of infected animals between treated and non-treated groups. Persistent efficacy is considered as an additional claim to therapeutic efficacy.
    Veterinary parasitology. 08/2014; 204(3-4):81-6.