Friday, August 10, 2012

Goat Parasites

Lots of people ask me about goat parasites and what to do about them. Well, here is what I have to say about that:

All goats can have internal and external parasites. Most goats become infected at birth by whatever parasites happen to be living on their dam or in her feces or in the soil. Internal and external parasites have a knack for being able to survive outside of the goat for a long period of time so they can simply be living in the soil and on the pasture waiting for a goat to come along. There's no way to avoid infection from parasites in goats. The only thing we can do is manage the infection so the parasites do not negatively impact the goat's health.

When a goat is born, they don't have any internal parasites. Their first exposure to the outside world is when they pick up things like coccidia, tapeworms, barberpole worm and other internal nasties. These parasites have a lifespan of a couple of weeks from when they enter the baby goat as an egg or dormant cyst. In these weeks the parasite hatches, morphs into an adult while using nutrients from the goat to do so, and then starts to reproduce. The eggs that are produced by the adult parasite either stay in the goat and become adults or are shed from the goat through its feces. Another goat picks these eggs up from the soil, pen or pasture and the cycle starts all over again.

Coccidia have a 3 week life cycle from cyst to adult. This is why you see kid goats get diarrhea around the 3-4 week old phase. The coccidia infected the goat at birth and at 3 weeks old, there's enough of them reproducing and living within the kid to cause intestinal damage, thus the diarrhea. It is very important to try to prevent coccidiosis by treating all kid goats who are 3 weeks old with a broad spectrum antibioitic that kills coccidia. There are several on the market, like Sulmet 12.5% drinking water solution, Corid powder, and Di-Methox 40% solution. These medicines kill adult forms of coccidia only so you must treat kids at 3 weeks old and then every 3 weeks after that until they are 15 weeks old. After 15 weeks they should be somewhat immune to coccidiosis. Adult goats rarely suffer from coccidiosis.

I currently prefer to use Corid. Corid kills adult coccidia by inhibiting their absorption of thiamine (vitamin B1). Some people feel this could cause thiamine loss in the goats too, so it is recommended to supplement any goat taking Corid with thiamine and other B vitamins. This can be done by giving the goats Fortified B Complex (it's "fortified" with extra thiamine) or thiamine/B vitamin gel. Since all of the coccidiosis medications are antibiotics, I also recommend giving any goats on them supplemental probiotics to replace any of the good gut bacteria that got killed by the medicine. I use Probios probiotic gel. I usually give the Corid to the kids in the morning, and then in the evening give them thiamine and Probios each day during treatment and for 1 week after. The thiamine and Probios will not hurt the goats in any way, so it is better to give lots of this and be safe.

Tapeworms are another internal parasite to worry about in kid goats. Goats over 6 months old tend to have less problems with tapeworms than kid goats for some reason. Kid goats who have lots of tapeworms will get a pot-bellied look and be smaller and slower growing than uninfected kids. It is recommended to preventatively treat kids for tapeworms and other stomach worms by giving them Valbazen dewormer at 1cc per 10 lbs weight, starting at 3 weeks old and repeated every 10 days for 30 days. Valbazen is okay to use in kid goats and non-pregnant adults but should NEVER be used in pregnant goats (or potentially pregnant ones) because it can cause birth defects and abortions. Repeat the Valbazen every 10 days for 30 days because it is only effective against adult tapeworms. The first deworming will kill all of the current adults but leave eggs and cysts in the goats to hatch and reinfect. The second deworming takes care of all the internal eggs that hatched after the first. The third deworming takes care of all of the eggs and cysts that were picked up by the goat from the environment and hatched into adults. The 30 day cycle is very important to use every time you deworm, regardless of dewormer chosen. This is the most effective way to deworm.

So now you have your kids on preventative coccidiosis medication and preventative dewormer. What about the adults?

The best way to manage parasites in adult goats is to monitor their condition frequently and only treat for worms when warranted. I never recommend to use a strict deworming schedule on your entire herd. Always deworm only the goats that have the worms! I have my own 4 step monitoring system for parasites.

1. Body condition - I want my goats to look sleek and shiny with just the right amount of weight. I don't want my goats to be too fat nor too thin. Parasites rob nutrients from the goats and cause them to be thinner than they should be. If I see one of my goats eating well but not gaining weight, I check for parasites.

Another external clue to parasites is the condition of the goat's hair. Their fur should be sleek and shiny. If it is dull and looks like it has split ends, the goat has worms. If the hair is shedding constantly and looks dry, the goat has worms. If when I brush the hair back and there are little bugs moving around, the goat has lice. Mites cause hair to fall out in patches. If the goat's tail is rubbed raw and missing lots of hair from scratching, the goat has pinworms that live around the anus. A goat's coat can tell you a lot about what is going on internally.

2. Mineral supplementation - This is very important to parasite management in goats. Goats need lots of minerals to stay healthy and any goats that are deficient in minerals are very susceptible to parasite problems. I supplement my goats with a loose mineral blend made specifically for goats called Sweetlix Meatmaker 16:8. It is a great all-around mineral that works for all types of goats (not just meat goats). I also supplement my goats with a copper bolus every 4 months. Copper is very important for goats and plays a huge roll in parasite control. Most goats are deficient in copper so they need extra copper even when getting it in their loose minerals. I use Copasure cow copper boluses that have been re-sized for goats. I give 1 gram of copper per 22 lbs of goat. The boluses are little gel caps filled with copper rods. It is important that the goats swallow the boluses without chewing them and on an empty stomach. It is also important to either wad the bolus in wax or shortening or follow bolusing immediately with Vitamin A, D, E gel. The wax, shortening, or gel helps to encapsulate the bolus within the goat's rumen and keep the rods in there for slow absorption. If the goat chews the bolus or eats it on a full stomach or takes it without wax, the copper rods can be flushed from the rumen and not absorbed.

3. FAMACHA - A cheap and dirty way to assess parasite load in goats is to look at the color of their lower eyelid membrane. This helps to tell you if the goat is anemic. Anemia is most often caused by barberpole worm (a very common internal parasite) that is sucking the blood from your goat. Where there is barberpole worm, there are usually other internal parasites so it is good to deworm a goat when they are anemic. The lower eyelid membrane should be dark pink or red in healthy goats. If is it white or light pink, the goat is anemic and needs deworming. Unfortunately FAMACHA does not tell you the type of parasites found but it does give you a good measurement of potential worm infestation. It is best to do FAMACHA on all your goats at least once a month, if not once a week.

4. Fecal samples - Once you have determined through lack of body condition, lack of mineral supplementation, and FAMACHA that your goat has internal parasites, it is important to find out what type of parasite it is and how large of an infestation. Fecal samples can tell you that. They are easy to do and can by done at home by anyone with a decent microscope. Just take a sample of poop from each goat (3-4 berries), process it per fecal sample instructions (found on the Fiasco Farm website), and look at the prepared fecal slide under the microscope. You should see little bits of fecal debris floating around on the slide. You should also be able to clearly see parasite eggs and cysts. Count up the different types seen and the amounts per type. Coccidia oocysts are tiny. Barberpole worm and other stomach worm eggs are larger. Liver fluke eggs have a flat spot on one end. Tapeworm cysts are square. There's lots of pictures on the internet of what parasite eggs in goats look like on a fecal sample.

Once you have figured out what types of worms are in your goats, then you can choose the appropriate treatment. Coccidiosis requires a sulfa-based, broad spectrum antibiotic (NOT A DEWORMER). Tapeworms are killed by Valbazen or Fenbendazole. Barberpole worm and stomach worms are killed by most dewormers, especially Ivermectin and Cydectin. Liver flukes require Ivomec Plus injectable (the "Plus" is actually what kills them so regular Ivomec won't work).

Like I said earlier, always use a 30 day deworming cycle when you deworm. Treat the goats every 10 days for 30 days in order to kill all the adult worms that have hatched. It is not at all effective to deworm once and then not again for 6 months! This does absolutely nothing to help reduce the worm population because the worm eggs that are in the goats and the worm eggs in the environment are still alive to reproduce. You need to treat twice more to kill these.

It is best to give any dewormer on an empty stomach and not give any grain or hay for at least 30 minutes after dosing to allow absorption of the dewormer. Giving dewormers during feeding time is not effective because the dewormers will get flushed out if the system by digestion of hay/pasture and grain. I deworm my goats in the morning before putting them out to pasture or feeding. Then I wait at least 30 minutes and put them out to pasture or give them hay. I do not give them grain after deworming for at least 12 hours because grain is quickly drawn into the digestive tract from the rumen and I don't want the dewormer to be taken out of the rumen faster than necessary. I want it to stay in there and be absorbed or at least be slowly drawn into the rest of the digestive tract.

Most people recommend using one brand and type of dewormer exclusively until it is no longer effective. This helps to cut down on possible worm resistance to dewormers. Worm resistance is a common problem because no dewormer is effective against 100% of the worm population in all goats. There's always going to be a small percentage of worms that are naturally resistant to a particular dewormer. For example (I am making these percentages up just for this example, so don't quote me!!), if you use Ivermectin 1.87% horse paste for deworming, it will kill 98% of the worm population in your goats. The 2% that is left will be the ones that will reproduce the next generation of worms. Now the next time you use Ivermectin, only 70% of the worms will be killed. 30% will be resistant due to genetics and will reproduce the next generation. The next time you deworm with Ivermectin, 40% of the worms will be killed and 60% will be resistant. And so on, and so on until a large majority of the worms are resistant to Ivermectin 1.87% horse paste. This will be when you notice that after you deworm, your goats still have rough coats, anemia and worms on their fecal samples. Time to switch dewormers. Your worms may be resistant to Ivermectin 1.87% horse paste but they won't be resistant to Valbazen because it is a totally different class of chemical. So you start the resistance cycle all over again by switching to a new dewormer and continuing with that one until resistance occurs.

Don't rotate dewormers every time you deworm because you could potentially create a "super worm" that is resistant to all dewormers. For example: You deworm with Ivermectin 1.87% horse paste and it kills 98% of the worm population in your goats. The 2% that is left will be resistant to Ivermectin and will reproduce. Then the next time you rotate to Valbazen and it also kill 98% of the worms. BUT there is a good possibility that the 2% of the worms left this time can be resistant to both Ivermectin and Valbazen, after having lived through the first deworming with Ivermectin and the second with Valbazen. Then you deworm again with Cydectin and kill 98% of those worms. Now there is a possibility that the 2% of worms left are resistant to Ivermectin, Valbazen, and Cydectin! Eventually if you rotate through all the classes of dewormers available often enough, you could create a super worm that is resistant to EVERYTHING!! Only rotate dewormers when the one you are using is no longer effective or your goats have a type of worm that isn't killed by the dewormer you normally use (ie: you use Valbazen but the goats have liver flukes you may have to switch to Ivomec Plus for the liver flukes).

Herbal dewormers work well as a preventative for both internal and external parasites. They do not treat any outbreaks of parasites but they make the goats' bodies an unwelcome environment where parasites prefer not to live. I use Hoegger's Herbal Dewormer in my goats and have had great results. I still have to use chemical dewormers occasionally but the necessity of these has been lower since starting the herbal. Also my goats seem to have less lice, mites, nasal bots, lungworms, and pinworms than before starting the herbs. The most important part of a herbal deworming regimen is to be consistent in giving each goat a proper dose of the herbs every week, continuously for life. The herbs do not work unless you are giving them consistently because they do not stay in the goats' systems for more than a week. I prefer to mix the dry herbal dewormer with molasses to create a ball. The goats love these little "treats" and will eat them out of my hand which makes a very convenient way to ensure they are getting their individual doses of herbs each week.

1 comment:

Lora Goulet said...

Rose, thank you for your well researched and clearly written post about goat parasites. You have done a great job including the many factors that contribute to goat parasite infections and all that is needed to enhance goat health so they are more likely to stay healthy. Goats are so wonderful. More people should raise them!