Anthelmintics are often over-used in the equestrian community. In a routine deworming approach for tapeworm, horses are dewormed once or twice a year, traditionally during the spring and autumn. Deworming programmes such as these inevitably lead to worms developing resistance to dewormers. Resistance is essentially the ability of worms to survive the killing effects of deworming drugs and a build-up of widespread resistance would have devastating consequences, especially as there are only two drugs (praziquantel and pyrantel (double dosed) available for the control of tapeworm in horses.
Worryingly, resistance in tapeworm has now been reported with apparent treatment failure reports in the USA for both praziquantel and pyrantel (Nielsen, M.K., 2023. Apparent treatment failure of praziquantel and pyrantel pamoate against anoplocephalid tapeworms. Int J Parasitol Drugs Drug Resist. 22;96-101). Special attention should therefore be paid to the management of tapeworm infections in horses to minimise the risk of resistance emerging.
Targeted deworming approach for tapeworm
Regular EquiSal Tapeworm testing now provides the means to adopt a targeted deworming approach for tapeworm. It is recommended that horses diagnosed as borderline or moderate/high are dewormed for tapeworm whilst those with a low diagnosis do not need deworming. Many horse-owners are already using a targeted deworming approach for redworms and roundworms, basing the use of dewormers on faecal egg counts which determine whether a horse has a worm burden that demands treatment.
Research has shown that a targeted worm control programme using the EquiSal Tapeworm saliva test controlled tapeworm infections and reduced the use of tapeworm dewormers at Bransby Horses. The published study reports the findings from 237 horses tested over the course of a year. Testing with EquiSal Tapeworm and only deworming horses with a diagnosed infection reduced the use of tapeworm dewormers by 86% compared to 6 monthly routine deworming strategies. Bransby’s vet consultant, Jeremy Kemp-Symonds, says “EquiSal has become integral to our targeted tapeworm control programme and has contributed to the very significant decline in tapeworm infection that we have achieved in recent years.” For more information click here.
The key message is to carry out routine testing and not routine deworming, reserving the use of dewormers for when they are recommended following diagnosis of a worm burden.