A questionnaire study of parasite control in Thoroughbred and Standardbred horses in Australia

Abstract

Background Information regarding parasite control practices currently used on Thoroughbred and Standardbred studs in Australia is lacking. Anthelmintic resistance (AR) is a global problem which has implications for equine health and welfare. Objectives To identify parasite control practices currently used on horse studs in Australia and investigate the frequency of use of management factors that have been associated with the likelihood of promoting or delaying AR. Study design Questionnaire study of equine parasite control on Thoroughbred and Standardbred studs in Australia. Methods An online questionnaire was emailed to 300 studs in Australia. Information obtained included property details, grazing management, anthelmintic use, non‐chemotherapeutic parasite control practices, use of faecal egg counts (FECs) and perceptions of AR. Results Seventy‐five completed questionnaires were received (25% response rate). Macrocyclic lactones (MLs) were the most commonly administered anthelmintics in mares and foals and less than 5% of respondents used targeted treatment regimens. The implementation of pasture hygiene practices was variable. The majority of respondents (97%) considered AR to be important; however, few respondents were aware of the use of FEC reduction tests for monitoring of drug efficacy. Main limitations The potential for nonresponse bias was the main limitation of this study. Conclusions Parasite control strategies on Australian stud farms remain over‐reliant on anthelmintic use. The frequent use of MLs is of concern for the increased selection pressure for AR. There is a lack of awareness of the importance of non‐chemotherapeutic strategies in integrated approaches to parasite control aimed at delaying the development of AR. This study highlights the need for greater veterinary involvement in the implementation of more sustainable parasite control practices with greater emphasis placed on surveillance through FEC testing.

Helminth infections in Italian donkeys: Strongylus vulgaris more common than Dictyocaulus arnfieldi

“…The present study is the first European countrywide survey providing data on parasite dynamics in donkeys and provides The frequency of anthelmintic treatment reported in this study is quite different to what has been reported in horses in Italy (Veneziano et al, 2015), where deworming was carried out by almost all owners (94.0%) and the frequency was mainly two or three times/year (68.6%) and comparable with other equine surveys (Schneider et al, 2014;Nielsen et al, 2018;Tzelos et al, 2019). Moreover, MLs (mainly IVM) were the most common drugs used to control endoparasites in Italian donkey farms, similarly to those used in horses (Veneziano et al, 2015;Becher et al, 2018;Nielsen et al, 2018;Wilkes et al, 2020). This supports the theory that deworming in donkeys is commonly performed with the same drugs and dosages used in horses (Gokbulut & McKellar, 2018).…”

“…(2010a), faeces were taken directly from the rectum of each animal, or alternatively picked up off the ground from fresh deposits (especially from nervous animals and foals) using plastic gloves. Fecal samples were stored in portable refrigerators (about 4°C) and individual fecal egg counts (FECs) were performed within 48 h, using a special modification of the McMaster method with a detection limit of ten eggs per gram (EPG) (Zajac & Conboy, 2011). The floatation medium used was the Sheather's sugar solution with a specific gravity of 1.250 (Lester & Matthews, 2014).…”

“…The floatation medium used was the Sheather's sugar solution with a specific gravity of 1.250 (Lester & Matthews, 2014). Based on visual morphological identification (Zajac & Conboy, 2011), each egg was classified as belonging to intestinal strongyles, Parascaris spp., S . westeri , O .…”

“…For each donkey, individual Baermann technique was also used to ascertain the occurrence of lung worm infection on 30 g of faeces, in a double layer of gauze, closed with an elastic band and placed in a funnel (Zajac & Conboy, 2011). The funnel was filled with tap water until the faeces were immersed.…”

A survey of control strategies for equine small strongyles in Lithuania

“…The identified resistance to macrocyclic lactones (ML) is an additional concern because no new medication classes or modes of action have been introduced since ivermectin in the 1980s (Cain et al, 2019). Due to the increasing resistance of gastrointestinal nematodes (GIN) to anthelmintic substances and the lack of new anthelmintic classes for use in horses, recommendations have been made to control equine parasites with improved sustainable management, with the emphasis on monitoring and targeted dosing based on faecal egg count (FEC) for individual farms and horses (von Samson-Himmelstjerna, 2012;Matthews et al, 2014;Wilkes et al, 2019). However, current knowledge gathered from a few questionnaire studies of European horse owners underlines high treatment frequencies and systematic drenching schemes with a limited use of faecal egg count (FEC) analysis (O' Meara et al, 2002;Relf et al, 2013).…”