Keeping your horse worm-free is a year round task. Each month the experts at Virbac – makers of Equimax and Eraquell wormers – offer advice on what you should be doing at this time of year.
During the summer, the weather conditions in the UK are optimal for the hatching of roundworm eggs on the pasture. Once hatched, worm larvae can develop very quickly and your horse will become infected when grazing. This lifecycle can be repeated 3 or 4 times over the summer, meaning that your horse can be at risk of worm-related disease.
Worm infections can be responsible for weight-loss, ill thrift, diarrhoea, colic and poor performance. It is essential that your horse is treated routinely for roundworms over the summer in order to prevent this. This is especially important if your horse is grazing with other horses. It is also worth remembering that the longer your horse spends grazing, ie if staying out overnight, the greater the exposure to parasites.
Summer Treatments:
During the summer, the parasites of most concern are the adult roundworms. The aim of your wormer treatments at this time is to reduce the number of adult parasites in the horses’ intestine. This will prevents the shedding of worm eggs on to the pasture and the subsequent re-infection of your horse. If we can reduce pasture contamination, we automatically reduce your horse’s risk of disease.
Ideal wormers to use over the summer are those which contain ivermectin or pyrantel- ask the suitably qualified person (SQP) at your local CWG store for a brand that contains one of these ingredients. If you use an ivermectin brand such as Eraquell, a second dose should be repeated 10 weeks after the first dose. Pyrantel products should be used every 4-6 weeks. You can use faecal egg counts to extend these dosing intervals.
Rotation of Wormers:
To help slow down the development of wormer resistance, one practice that you can adopt is to rotate the wormer drug you use over the summer grazing season Virbac Animal Health advise that after 2 years using Eraquell (ivermectin) over the summer, you should change to a brand containing pyrantel during the 3rd summer. You can discuss this with the SQP at your local CWG branch. The SQP will ensure that you are correctly rotating active ingredients and not simply brand names. Remember to pick up your Equi-Club Wormer Planner in store to aid you with your dates on when to worm your horse or pony and with which wormer – it helps makes this task more straightforward!