An internal parasite eradication plan

Our flock grazing the Rock Pasture in late April of last year; this is one of the five pastures that will be grazed only by cattle this year until July 1.

I knew when we brought in our sheep from pasture last year that I’d have to develop a plan to deal with internal parasites this spring. I didn’t know at that time exactly what we’d be facing, but after the “perfect storm” for parasites last summer, I knew that dealing with its aftermath in 2017 would take some research and serious thought. It was my hope last fall that a harsh winter would provide some winter kill. Unfortunately for parasite control, this past winter was not anywhere near harsh. As our temperatures warmed to a lovely (but wet) spring, I dove into finding the best way forward for our farm and sheep.

I have several competing goals. I want to provide the flock the best possible feed, especially those who need the most nutrition. I would like to keep our out-of-pocket costs down as much as possible. I need to allow our ewes to instruct this year’s lambs how to graze — which plants are and are not safe to eat. I hope to set up our farm for several years of low-parasite grazing. And despite possible increased costs for this year, I hope to continue to coat our sheep and provide our customers with the best possible raw fleeces — which means smooth fencing (to protect their coats) wherever they graze.

The trick is finding a way to maneuver through this list, maximizing the positive — and I think I’ve worked it out. Unlike most years, when our sheep are out on pasture as soon as there is any green growth, our adult ewes and their lambs are still dry-lotted in the Sheep Barn and the driveway that leads to it. They are being fed the best alfalfa and a specially designed grain blend. Keeping them in meets two goals: the lambs have time to gain size and strength to fight off the onslaught of parasite larvae they will encounter once they go out onto pasture, and the lack of grazing allows the pasture to grow tall before the sheep enter. Parasites live in the lower 2″ to 3″ of grass. With a deep, dense pasture, it will take a while before the lambs get down to where parasites await them. The ewes can get a big enough mouthful to get down to the bottom, but the lambs won’t be able to for some time. Delaying the sheeps’ entry into the pasture means that the parasite larvae that hatched out early in the season have already died, never having been near our sheep. Although that alone is not enough to keep them safe, it is something.

In May the lambs and their mothers will be put out onto first one and then another of our seven pastures — the two that I suspect have the lowest parasite levels. These two fields have been in our rotation for the fewest years and have the widest variety of vegetation. They are also larger than the other pastures, so there is less grazing pressure (more space for each sheep, and fewer eggs dropped per square yard). After our lambs learn how to graze in these two pastures, we will wean them in the Sheep Barn, where we will also deworm them and clean them up for their next move.

About a week after weaning, they will join our yearlings and a couple of thin old ewes and be trailered to a friend’s farm, where they’ll be released into a four-acre field that has been grazed by only a handful of cattle. The perimeter fencing is smooth, and our wire panels will subdivide the four acres into four plots so we can rotate the sheep about once each week. The plan is to graze them there for about a month, beginning in early June. Since sheep and cattle don’t tend to share parasites, the cattle from the friend’s farm will come to our pastures. By about July 1, our own five fields should be relatively clean of parasite eggs and larvae, which will allow our sheep and the friend’s cattle to all return to their own fields.

A number of our adult sheep will remain dry-lotted and will not graze this year. The adult rams will be kept in one area, and the adult ewes will be divided into two groups by condition. Those requiring weight loss will remain at the Storage Barn on carefully measured rations of grass hay, while those needing to rebuild or gain weight will be housed in the Sheep Barn eating alfalfa hay and a bit of grain. We weren’t able to slim down the unbred adult ewes over the winter, because they were housed with last year’s unbred lambs who needed higher levels of nutrition for growth. With the yearlings out among the lambs, we will hopefully be able to slim down our adult “fatties” in time for breeding this fall!

Once our five fields have been vacant or grazed only by cattle for this first half of the year, they will be considered clean of parasites — and should remain so for a while, since we’ve been working on emptying our sheep of parasites. The two fields that the lambs and their mothers will graze in the next few weeks will be pulled out of the rotation as of June 1 and will remain vacant for the second half of the grazing season. They will not be open for grazing until next spring. Feeding out hay this summer will be an added expense, but no more than the cost of lambs lost to parasites last summer — and with a lot less heartache!

If you have questions, please ask away. I’ve given this plan a lot of thought, and I hope I’ve considered every angle. But there is no way to know whether it might work until the plan is tested — or questioned!

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