Why is tapeworm control so important for our horses? Here’s what Virbac say…
Tapeworms are recognised as a risk factor for various types of colic in horses. The most common species, Anoplocephala perfoliata, is the main tapeworm associated with health problems. The adult tapeworm tend to cluster around the narrow junction between the small and the large intestine (the ileo-caecal junction). This can result in blockages which prevent the passage of food through the intestines resulting in an impaction, a potential cause of colic.
Horses become infected with tapeworms by eating forage mites containing the tapeworm larvae. These mites are not visible to the eye but are often present in large numbers on summer pasture, or occasionally hay and bedding. These larvae then mature to adult tapeworm within the horse and start to shed eggs within 6-10 weeks.
Tapeworm eggs are passed in segments which means that they will not necessarily be detected by routine faecal egg count testing. Specific testing must therefore be carried out to check for tapeworm and to determine whether a horse needs treating. Such tests measure antibody levels, in either blood or saliva, and give information regarding previous exposure to tapeworm.
Whilst horses of all ages are at risk of tapeworm, studies have found that younger horses require more tapeworm treatments. Antibody levels have also been shown to increase in horses greater than 16 years of age, which suggests an increased susceptibility of older horses.
If testing is not performed, a wormer that is effective against tapeworm should be incorporated into the annual worming programme. This may be given once or twice a year depending on age, previous worm test results and other risk factors. Traditionally tapeworm treatment has been recommended in the spring and autumn, at the start and at the end of the grazing season. Only two wormer ingredients are effective against tapeworms – pyrantel (used at twice the standard dose rate) which controls one species of tapeworm or praziquantel at the standard dose, which kills all three species of tapeworm known to affect horses.
It is important to remember that worm populations can be reduced by good pasture management. Frequent poo-picking, at least twice but preferably three times per week is vital. Keeping young stock separate from older horses will prevent them from contaminating the pasture, and ensuring sufficient grazing per horse will also reduce pasture contamination. Rotating and regularly resting paddocks in addition to co-grazing with sheep can all help to reduce the risk of infection.
For stress-free worming, join the Speedgate Parasite Control Programme to receive our handy reminder service, as well as 10% off every 3rd wormer. For more advise or information on worming, speak to one of our SQP’s by calling 01474 872313.