Barberpole and Liver fluke parasites in small ruminants
Its summertime which means does have had kids, the sun is shining, and the grass is growing! While this sounds pretty ideal for you and me, this also sounds like a breeding ground for parasites. Parasites love the weakened immune system of the doe that just kidded, the sun and humidity it brings, and the grass it can hide in.
Arapawa grazing on tall grass
Growing up, I learned that you deworm on a schedule, once in the spring and again in the fall (some people do it once a month!), and as the animals look like they need it. While that may have worked for several people 10+ years ago, the parasites have become more resistant due to the constant deworming, underdosing, and not using the proper dewormers.
I am no vet, nor do I claim to be. I started to research internal parasites after losing a few animals to Haemonchus contortus (Barberpole worm). I became fascinated by the life cycle of the parasites, how quickly they reproduce, and the amount of damage that can be done to the animal in just a few days. I started to gather as much information as possible and started developing a program that would work for us. What we were doing wasn't working anymore for our program, so it was time to change things up.
Now I firmly believe it is vital to have a vet that you can work with, but just some words of advice... not all vets are equal. I mean that your vet knows how to run a fecal and will tell you what its eggs per gram are, but they probably aren't going to tell you what kind of parasites they are. They may be "old school" and suggest scheduled deworming, which many vets were taught. Talk around and try to find a vet knowledgeable in internal parasites, and it will genuinely help you out!
Symptoms of parasites
- Fluid under the jaw
- From pain
Loss of appetite
Just "died all of a sudden"
It can be overlooked by inexperienced owners
I will only be talking about Barberpole worm and Liver fluke, as they are the two most deadly parasites. Now there are many other parasites like tapeworm, lungworm, and cocci (which is not a worm like the others). Cocci would need its own entire writing!
Multiple barberpole eggs in a McMaster test
The Barberpole worm is a bloodsucker that will destroy the lining of the stomach to access the bloodstream. The destruction can cause anemia, scours, and weight loss due to the animal's inability to digest feed completely. The worm feeds off of their host after they attach to the wall of the abomasum. The worm will cause extreme anemia and can get out of control very quickly. The lifecycle of this parasite is 2-3 weeks, and a single worm can lay 10,000 eggs a day. A single parasite can drink .05 milligrams of blood per day. That doesn't sound like a lot, but if you have a 150 lbs goat, that is a cup of blood per day, and a goat that weighs 150 lbs has roughly 20.32 cups.
Liver Flukes burrow tunnels in the liver, causing scarring as the body tries to repair the damage. The scar tissue is not functional, and the liver loses part of its ability to function. Because of the toxins in the liver, it can severely damage other organs. Animals typically show signs of being depressed and anemic. Goats of any age are not able to create an immunity to Liver Fluke. A high infestation can cause death in 1-2 weeks. One fluke can have anywhere from 5,000-20,000 eggs! (wow, that is a lot!)
FAMACHA scoring card
One of the best ways to check for blood-sucking worms is by checking the goat's FAMACHA. This is a test where you pull back the eyelid to match the color of the flesh on the inside of the eyelid. There are plenty of helpful tips on the internet that can assist in learning how to do FAMACHA testing on your livestock, and you can even become FAMACHA certified online! It is important to note what your animal's FAMACHA is. Some animals tend to have a lower FAMACHA, which is typical for that animal. Use the FAMACHA as a guide, not an absolute.
Now, when in doubt, talk to your vet! Blindly treating your livestock with dewormers can cause the parasites in your area to become resistant to the dewormers you are using. Most sheep and goats are already resistant to moxidectin-based dewormers due to their overuse and misuse. Misusing dewormers can look like under-dosing your goats for their weight, not using the correct dewormer for the type of parasites your animal has, and not using a follow-up dewormer. This has been proven to be more harmful than helpful. You can only be 100% certain of what parasite you are dealing with by doing a fecal test.
Viewing a slide - Photo credit Eric Rapp/Rare Hare Barn
One of the easiest ways to find out what parasites your goats are dealing with is by doing a McMaster test, which is a fecal test. The McMaster test uses a specific slide that allows the parasite eggs to float to the top and the debris to sink. The test is done by mixing manure with a flotation fluid. The slide has grids on it, and you count a specific parasite's egg in the slide. Once you have calculated the eggs in both grids, you multiply the eggs x 50, and you get your eggs per gram. The University of Rhode Island has a great resource on how to do your own McMaster test at home (here). If you do not want to do your own test, work with your vet, and they should be able to do a fecal test for you relatively cheap. You can also collect fecal material and mail it in (here are a few places you can mail it to)
As with anything, use your observation skills. Do your goats have a high fecal egg count and a low FAMACHA? Resilient goats are better able to tolerate their parasite load, while resistant goats have fewer parasites.
Prohibit dewormer. Purchased in powder form and mixed to instructions.
There are three classes of dewormers that are approved in the United States. The Benzimidazoles (Valbazen), Macrocyclic lactones, which are your Avermectins (Ivomec) and Milibimycins (Cydectin), and Nicontinics (Levamisole). Each dewormer targets specific parasites, so make sure you read what they treat and the dosage. Some dewormers are not suitable for pregnant does, have a protracted withdrawal, or have special instructions.
Internal parasite prevention can be done! A few things that can help prevent parasites are:
Culling for parasite resistant genetics
Pasture rotation and rest
Mixed species grazing
Minimum grazing height (no lower than 3 inches)
Now I know I just said don't schedule deworm your animals, but there is one instance where I will. Does suffer a temporary immunity to parasites two weeks before kidding, and their immunity is restored four weeks are kidding. I believe it is important to deworm yours does a few days after kidding, as parasites can take a doe down quickly if you are in an area with a high parasite population. I prefer to only use Prohibit (levamisole hydrochloride) as 1) my last resort, no other dewormer is working dewormer, and 2) for does that just kidded. This one is one you have to read the instructions and mix up yourself.
While parasites may seem daunting, you can handle them. Many great resources help you figure out what would work best for your livestock and program. No deworming program is going to be the same for each farm. Find a vet you can trust, watch out for parasite symptoms, and get your fecals done! If you have any questions feel free to reach out! I am always happy to help in any way I can.