Drenches (anthelmintics) continue to play an important role in worm control for sheep, goats and other grazing livestock. However, resistance to drenches is widespread and sometimes severe. Drenches should only be used if tested and shown to be effective on a farm and then used as part of a good, overall worm control strategy. In this regard, WormBoss (wormboss.com.au), along with the animal health information on NSW DPI’s website, is an invaluable resource regarding best-practice sheep worm management.
Following is an overview of the different drench types available. Note that most drenches are not registered for use in goats or alpacas. Sheep drenches can only be used in other species, for example, goats or alpacas, if you have written directions from your veterinarian. Remember that dose rates recommended for sheep are usually inappropriate for goats and alpacas. Seek veterinary advice.