Barber pole worms. A phrase I was familiar with, but only in a passing way until a few weeks ago.
We recently weened our flock of lambs, at approximately 10 weeks of age, separating the ewes from the rams. We had a total of 21 rams, two adults and 19 lambs. (Once again, we had a hugely skewed sex ratio this year, about 75% male). We now have 10 rams total. We lost a ram a few weeks ago. He was small. It sometimes happens. We didn’t think a whole lot of it. Then a few days later, we lost another one, and I started calling our vet. They basically told me, “we’ll just send the pathology out to the Washington Animal Disease Diagnostic Lab (WADDL) at Washington State University in Pullman. Cut out the middle man and talk to them directly”. So, two Thursdays ago, after several “let me transfer you” phone conversations, we found ourselves driving to Pullman with a lamb that we didn’t expect to make the trip (he didn’t). Results were extreme anemia and presence of Barber pole worms (Haemonchus contortus).
One of the reasons we raise American Blackbelly sheep is because they are naturally disease and parasite resistant. They also have intact wild instincts, which makes them hard to catch and handle. Therefore, we have not been checking for parasites or “drenching” our flock with antihelmintics (ie drugs that kill round worms) in the four years we’ve had sheep on our farm. We got our first animals in May 2012, and have never had an issue – though to be honest – its possible that the worms have always been present, just not at a lethal level. We got a new ram May first of this year, and its possible that he came in with them and the population exploded from there. It’s also possible that a low level pasture presence of worms was increased due to weather or the height of the forage. ATTRA has a good piece on Barber Pole worm biology here.
In the past, the way ranchers have dealt with worms in sheep is to treat them monthly with a wormer. This has lead to worms that are resistant to the wormers on the market. This is decidedly NOT a good thing. In a brilliant bit of science, in 1996, Dr. Faffa Malan, a vet in South Africa, realized that what was needed was the ability to quickly assess each individual animal for level of barber pole worm infestation, without using a microscope and taking fecal samples. Because the worms cause anemia, he realized that the skin on the inside of the lower eye lid was a good indication of anemia in sheep. Nice and pink = no dosing needed. Pale or white = dose required. This process has been distilled into an eye chart called a FAMACHA chart (which stands for Faffa Malan’s Chart). Additional information on the system in this PDF, and great articles from the Animal Consortium for Small Ruminant Parasite Control on managing your herd this way here.
The idea is that by only treating highly infected individuals, and leaving a background level of weaker worms, you are no longer selecting for the super worms who are resistant to the wormer. The system also allows you to selectively cull animals that show less natural resistance to infestation, ultimately increasing the natural resistance of your herd (which is what happened to the Blackbelly naturally when they were on their own in Barbados – and how they became more naturally resistant to parasites in the first place).
Ideally, formal training in the system is recommended. But we knew the basics, and the WADDL had mentioned how anemic our examined lamb was, so we knew we should be able to see anemia. We corralled our sheep into a small space using livestock panels, and then one by one, my wonderful husband grabbed each one (it helps that the males come with “handles”, ie “horns). We don’t have equipment for handling sheep in the common “squeeze shoot” set-up, which makes handling them difficult. In this case, because we were now completely freaked out, we did drench each of our animals with Ivermectin, a common wormer. But we examined each lower eye lid, and we marked each sheep with a stripe down the back if they were anemic and a stripe across the butt if they seemed pretty healthy. All of the young males had pale eyes. It should be noted that while we originally ran the males and females together when we first got our new ram, they were shortly thereafter separated, and have been in different pastures for the past month or so. We did treat the females as well. Some of the young ewes were pale, but overall, they were in much better shape than the males, and the adult ewes and rams were all fine. Time when separated? Specific pasture they were on? Lack of weening stress because the young ewes stayed with their mothers? We don’t know for sure.
In all, and I am truly mortified to say this, we lost 11 young rams. ELEVEN. Through our own complacency in assuming all was fine with our herd and not actively checking them. Damn. My husband and I both walked around in a daze for a week, reeling mentally from our own failure to take better care of our animals. The one small thing that has helped us is knowing that nature selected for the strong. A recent article on the Animal Consortium for Small Ruminant Parasite Control website is titled “Stop Selecting for Sissy Sheep (and Goats)!” Well, in a very poorly executed way, that’s what has happened on Miles Away Farm.
After two weeks of death, we haven’t lost an animal in a couple of days. Fingers crossed that this horrible period of time has passed. In the future, we will check our herd at least twice per year, and most definitely at weening, which is when the lambs are the most vulnerable. From now on, we’ll be doing our best, as much as possible given our current set-up, to make use of the best practices covered in this piece on Managing the Barber Pole Worm, summarized here:
Pasture rotation, especially with long rest periods
Grazing browse or eating high off the ground
Using good nutrition
Grazing cattle or horses with sheep or goats
Tillage of pastures
Monitoring parasite infection using FAMACHA© or fecal egg counts
Culling animals with the most parasite problems
Deworming around kidding time
© Miles Away Farm 2016, where we write about not only the successes but the failures on this farm, so that you can learn from our experiences. It’s not all cute animal pictures and flowers and butterflies, though, after the last few weeks, I so so wish it was.