Thus, they should be used judiciously. The current recommendations are to use one type of dewormer for one year and then switch to another type the next year and still another type the third year. The process would start anew in the fourth year. Those producers that do wish to control tapeworms will have to give an annual dose or two of Albendazole during tapeworm season. Fecal exams by an experienced veterinarian can be of assistance in determining when to deworm or if parasite resistance to antheimintics is a problem.
Pasture management is critical in preventing parasite problems.
One should keep a short record of when and how long pastures have been grazed and by what specie or class of animal. Safe pastures are those last grazed when weather was hot, those that have been grazed by cattle or horses before sheep turnout, those that have had a cutting of hay made before grazing or newly established pastures. Lets walk through what I would recommend as a parasite control program for a Midwest or temperate climate condition for a producer lambing in the spring and going to pasture with ewes and lambs. Seven to 14 days later, treat again. Turnout should be to the safest pasture available.