 Regular worming is essential as parasitic worms are a major cause of un-thriftiness, and high levels of infestation can result in serious illness, and sometimes death. There are a number of different worming products on the market, in different forms such as liquid, paste, granules, or powder. It is recommended that owners follow a good worming programme along with good pasture management. Good pasture management should include not over stocking a pasture, resting the pasture, rotating the pasture with other animals e.g. sheep, goats, cows, worm all horses that share pasture on the same day with the same wormer, and pick up the droppings from the field on a regular basis. To reduce a worm burden it also helps to keep your stable clean and do not feed your horse directly off the stable floor. Any new horse to a group should be wormed on arrival and stabled for 48 hours before joining the group. It is good practice to have your horse's dropping analysed for a worm count. Coming soon will be more information about faecal egg counts. Many horse owners find worming a confusing business. For example with red worms there are: - inhibited encysted small red worms, large red worms and small red worms. Horses can carry pin worms, lung worms, thread worms, large round worms, bots, and tapeworm! No wonder we get in a muddle!
In basic terms there are three types of internal parasites, roundworms, tapeworms and bots.
Roundworms are the largest group. They are cylindrical in shape. They include lung worm, thread worm, large round worms, inhibited encysted small red worms, large red worms and small red worms. Best times to treat: Some manufacturers recommend a routine wormer all year, other suggest for the grazing season.
Tapeworms are a type of flatworm and there are three species that horses can carry these are:- anoplocephala perfoliata, anoplocephala magna and anoplocephala mamillana. Best times to treat are March / April and September / October. Some products must be given as a double dose therefore carefully read instructions.
Bots are not worms but the larvea of the insect of the horse bot fly. Best time to treat is in the winter after a sharp frost - this will have killed the adult flies.
There are four chemical families for horse wormers:-
Macrocyclic Lactones – Moxidectin and Ivermectin. Treats bots, small red worms, large red worms and lung worms.
Pyrimidines–Pyrantel Embonates. Treats large round worms, large red worms, small red worms, seat worms/pin worms and tapeworms (all species).
Benzimidazoles– Fenbendazole and Mebendazole. Treats round worms, large red worms and small red worms. NB: only fenbendazole based: Panacur Equine 5 Day Guard and Equest are licenced for the treatment of encysted small red worms.
Isoquinoline Pyrazine– Praziquantel. Treats all three species of tapeworm.
Treatment periods
Moxidectin – every 13 weeks
Ivermectin – every 8 – 10 weeks
Pyrantel – every 4 – 8 weeks
Fenbendazole – every 6 – 8 weeks
Mebendazole – every 6 weeks
Here is an example of a worming programme
Winter after the frosts (Decemeber / January) treatment for bots.
Spring (March / April) treatment for tapeworms.
Summer (May) routine wormer.
Summer (July) routine wormer.
Autumn (September / October) treatment for tapeworms.
Winter (November) treatment for encysted small red worms.
Each year you should rotate the chemical groups in the main wormers you use.
The Importance of Worming
Horse ownership is a huge commitment, both time-wise and financially, a fundamental part of which is looking after your horse’s health and well-being. One of the main threats to your horse’s health is internal parasites. A parasite is an organism that lives in or on another ‘host’ organism (i.e. your horse) from which it obtains food. Parasites may or may not be harmful to the host. Parasite infections can simply be a minor irritation to your horse and may result in poor condition, with your horse not benefiting from the full nutritional worth of its feed. But infections can also prove fatal.
Reducing the infection of internal parasites in your horse is one aspect of horse management which you can control. The aim of any worm control programme is to prevent the worm from completing its life cycle through the combined use of effective pasture management and equine anthelmintics.
Ask the Experts
Intelligent Worming. If you want to take the worry out of worming Intelligent Worming takes the guess work out of worming. They can offer you advice and tailor a worming programme to suit any horse. Intelligent Worming will find out for certain what levels of worms are in your horse and pasture. They use faecal egg counts analysis in conjuction with other information to assess safety of reducing chemical wormers. It ensures chemical wormers are only used when required, which can save you money. Please visit www.intelligentworming.co.uk for more information.
The Blue Cross has produced an excellent information leaflet on Worm Control and Pasture Management. Please click here to go to the information leaflet section of the Blue Cross website for more information.
www.wormingyourhorse.info provides you with information on equine parasites and their control, and will help you make the important decisions in building a worm control programme for your horse.
You can also discuss worming with your vet as they can help you to put together a worming programme.
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