A combination of natural methods works in preventing worm issues in sheep
Internal parasites in sheep are rapidly becoming a global problem for producers. I remember entire lectures in college devoted to how to treat sheep for parasites without contributing further to anthelmintic-resistant parasites. Most of what was taught in class was how to use various chemical dewormers. There was no talk of prevention or natural alternatives.
But an ounce of prevention is worth a pound of cure, so let’s start there. Most prevention boils down to good grazing management. Ideally, sheep should not be in a pasture for more than three days (daily moves are even better, but I know this isn’t always possible), in order to reduce the number of worm eggs that the sheep ingest. After sheep come off of a pasture, it should be rested for a minimum of three to four weeks — longer in cold, wet conditions.
Care should be taken to ensure there are several inches of grass left when sheep leave a pasture, as parasites live in the bottom few inches of grass. This also has the added benefit of aiding in overall pasture health and regrowth.
If you have another species of livestock on your farm, such as cows, you can further reduce your reliance on chemical dewormers by combining cows and sheep into a single flerd. By alternating which species grazes a pasture, parasites can be killed through a dead-end host. In simple terms, if a cow eats a sheep parasite, the parasite dies, and if a sheep eats the cow parasite, the parasite dies. Chickens are also useful at pasture sanitation and have the added benefit of controlling fly populations as well.
One thing I think a lot of shepherds overlook — partly out of fear, partly out of lack of information — is the role of copper in preventing parasite problems. Most shepherds know that copper is toxic to sheep, so sheep minerals have very low levels of copper, and sheep should not consume mineral mixes formulated for cattle or goats.
Last spring we switched to a cafeteria-style mineral feeder that has 20 separate slots for minerals, vitamins and salt. One of the minerals is copper. The sheep have free access to the mineral feeder and can dose themselves for exactly what they need. This eliminates the risk of copper toxicity.
Before you think that animals are not capable of knowing what their body needs, I invite you to read Nourishment by Fred Provenza. Remember that animals have been balancing nutritional needs for thousands of years, before the invention of scientists, nutritionists and chemical dewormers.
According to Dr. William Albrecht, sheep given the appropriate amount of copper and other minerals will not get worms or protozoa-type infections. As long as a sheep has the appropriate amount of copper in its body, the worms are prevented from staying in the sheep’s digestive tract. Since worms need the digestive tract as part of their life cycle, they quickly die.
An interesting fact is that black sheep need roughly six times more copper than white sheep. Merino sheep require similar amounts of copper as black sheep.
Finding a sheep mineral mix can be challenging enough at the farm store — much less finding one for a specific physiological stage of life. I’m quite sure that if you asked a store associate for sheep minerals specifically formulated for black sheep, they would look at you as if you were in fact the black sheep!
By using the cafeteria mineral feeder, the sheep can eat exactly to their bodily needs. Since making the switch to such as mineral feeder, we have not had to deworm our ewes, and we only dewormed a few lambs that were struggling (as of this writing, in early spring). Typically, we would have dewormed the sheep twice throughout the summer and autumn, and we would potentially have a lamb with chronic diarrhea.
Throughout the summer I monitor the color of the inside of the lower eyelid. A healthy pink color indicates the sheep are healthy; a pale pink or white color would indicate anemia from excessive parasite burden. Every sheep I have checked so far has a healthy pink color.
Another method we use is feeding pumpkins every fall, as the seeds work as a natural anthelmintic. The animals love eating them, and it makes for great videos for social media. We live in an area with a lot of Amish farmers that grow pumpkins for the local big-box stores. We go through after their first harvest and pick seconds for our animals to enjoy. We can get several truckloads for cheap like this.
By using a combination of prevention with good pasture management, natural methods like pumpkin seeds, and supporting the sheeps’ bodies with proper mineralization, we are able to reduce our dependence on chemical dewormers. This also saves money and time from not having to dose animals repeatedly throughout the year.
Kyle Brisendine is a second-generation farmer at Willow Farm in Homer, Michigan. Willow Farm raises grassfed beef and lamb as well as pastured pigs and poultry (willowfarmllc.com).