There is a lot of debate on how often sheep should be wormed. Younger animals, lambs and yearlings and pregnant or ill animals are most at risk. As sheep get older they naturally build up resistance to parasites. Worming too often and under dosing can lead to resistant strains of worms. The best way to know if you need to worm your animals is to send off a sample of their droppings for a worm count. For a lot of people this it either too costly or time consuming so they opt for routine worming several times a year. We typically use a wormer like Combinex or Supaverm that treat for liver fluke as our land is in a high fluke area. Another good wormer is Oramec and also Ivermec Super, there are also more natural alternatives available. If you are routinely worming make sure you don’t under dose and try to alternate between different wormers. Most wormers are administered orally as a drench, either with a specialist gun/applicator or with a large syringe, best to just use a syringe if you only have a few sheep. Ivermec Super is administered by subcutaneous injection. You can buy wormer from an agricultural shop, online and sometimes from your vet. You may even be able to get a leftover batch from a local farmer or neighbour. It is important to worm you sheep if you suspect they have a worm burden, they can loose condition, become ill and even die from a heavy worm or fluke burden. But it is also important not to over do it as wormers are harsh on the sheep’s gut and as mentioned above, unnecessary worming created resistance in the parasites. A natural inexpensive way of reducing the worm burden is pasture rotation, leaving a field to rest without sheep for at least 2-3 weeks naturally breaks up the worms life cycle, as does grazing the pasture with a different animal, for example horses or ponies after the sheep have moved on. So in that sense it is a good idea to time worming with moving to a new field/fresh pasture, that way your sheep won’t contaminate the fresh grass with worms too. Another way to ensure you don’t get heavy worm infested sheep and land is make sure you don’t get overstocked, overstocking always leads to poor animal health and condition. Sheep with heavy worm burdens can display different symptoms depending which parasite they are affected by. Some cause loose stool and diarrhea, others cause an animal to loose body condition and some can be very acute and life threatening. Typically if you have a few healthy pet sheep you are unlikely to encounter any serious problems with worms, and dosing you sheep a couple of times a year, or sending of a stool sample should be plenty sufficient. If in doubt and for advise it is always best to consult a vet.