Anemia in goats is overwhelmingly caused by a single blood-feeding stomach worm called Haemonchus contortus, and treating it requires more than just reaching for a dewormer. The barber pole worm, as it is commonly known, attaches to the lining of the abomasum and drains blood directly, sometimes killing a goat before the owner notices anything is wrong. Effective treatment depends on catching the problem early, choosing a dewormer that still works against the local worm population, supporting recovery with good nutrition, and managing pastures so the cycle does not repeat.
Why Haemonchus contortus Is the Usual Culprit
Several gastrointestinal worms infect goats, but H. contortus stands apart because it feeds on blood rather than simply irritating the gut lining. Each adult worm can consume a tiny amount of blood per day, but infections often involve thousands of worms at once, draining enough blood to cause life-threatening anemia in a matter of weeks. The disease it causes, haemonchosis, is considered the most important parasitic condition of sheep and goats worldwide.1CrossRef / Livestock. Haemonchosis: dealing with the increasing threat of the barber’s pole worm Unlike worms that cause diarrhea or weight loss, barber pole worm infections can progress with little visible change in the feces. The goat simply becomes pale, weak, and eventually recumbent as its red blood cell count drops.
That said, not every anemic goat has worms. Tick-borne diseases like anaplasmosis, caused by Anaplasma ovis infecting red blood cells, can produce a similar picture of pale membranes and weakness.2PubMed. Evaluation of oxidant/antioxidant status, trace mineral levels, and erythrocyte osmotic fragility in goats naturally infected with Anaplasma ovis Nutritional deficiencies in iron or cobalt can also cause anemia, particularly in young kids raised indoors on milk alone. Before jumping to a deworming protocol, it is worth confirming that worms are actually the problem, especially if fecal egg counts come back low or the goat has heavy tick exposure.
Using FAMACHA to Catch Anemia Early
The FAMACHA system is a practical, pen-side tool that lets you estimate a goat’s level of anemia by comparing the color of its lower eyelid mucous membranes to a standardized color chart. The chart runs from 1 (deep red, healthy) to 5 (white, severely anemic). You pull down the lower eyelid, compare what you see, and assign a score. It is not a perfect diagnostic, but in areas where barber pole worm is common it is the fastest way to figure out which animals need treatment right now.
Research on farms in the southern United States found that FAMACHA scores correlated significantly with packed cell volume (PCV), the lab measure of how much of the blood is made up of red blood cells. When scores of 3, 4, and 5 were all classified as anemic and the PCV cutoff was set at 15% or below, the system caught every truly anemic animal in both sheep and goats. The trade-off was that it also flagged some animals that were not yet clinically anemic, meaning you would treat a few goats that did not strictly need it.3PubMed. Validation of the FAMACHA eye color chart for detecting clinical anemia in sheep and goats on farms in the southern United States A later study looking specifically at crossbred Boer goats reinforced that in goats, it is risky to leave score-3 animals untreated. The sensitivity at that cutoff was too low to gamble on skipping them.4PubMed. Sensitivity and specificity of the FAMACHA(©) system in Suffolk sheep and crossbred Boer goats
The practical takeaway: if a goat scores 3 or higher, treat it. If it scores 1 or 2, leave it alone. This approach, called targeted selective treatment, means you are not blanket-deworming the whole herd, which slows the development of drug resistance. On a goat farm in tropical Mexico that used FAMACHA along with body condition scoring and fecal egg counts for six years, over half the herd was left untreated in any given cycle, and fewer than 15% of goats needed more than one treatment per year.5Small Ruminant Research. Building a combined targeted selective treatment scheme against gastrointestinal nematodes in tropical goats
Choosing the Right Dewormer
Three main classes of chemical dewormers are used against gastrointestinal worms in goats: benzimidazoles (like fenbendazole and albendazole), macrocyclic lactones (like ivermectin and moxidectin), and imidazothiazoles (like levamisole). Each class kills worms through a different mechanism, which matters because resistance to one class does not necessarily mean resistance to another. The problem is that on many farms, worms have developed resistance to all three.
Reports of multiple anthelmintic resistance in goat herds go back decades. One study documented H. contortus surviving treatment with ivermectin, levamisole, and benzimidazole drugs on a single goat operation.6PubMed. Multiple anthelmintic resistance in a goat herd Similar simultaneous resistance to benzimidazoles, levamisole, and rafoxanide was found on a goat farm in Kenya.7PubMed. Multiple anthelmintic resistance on a goat farm in Kenya More recently, a field study in Thailand found that neither eprinomectin nor albendazole showed adequate efficacy against strongyle nematodes in dairy goats, and combining the two drugs did not improve outcomes, likely because the worms carried resistance mechanisms against both.8Current Research in Parasitology & Vector-Borne Diseases. Effectiveness of eprinomectin, albendazole and their combination therapy against strongyle nematode in dairy goats
This is why running a fecal egg count reduction test (FECRT) is so important before committing to any dewormer. You count the eggs in a fecal sample, treat, then count again 10 to 14 days later. If the egg count has not dropped by at least 90 to 95%, the drug is failing. Without this check, you can deworm a goat and assume it is recovering when the worms are actually shrugging off the drug entirely.
Dosing Goats Is Not the Same as Dosing Sheep
One of the most common and consequential mistakes in goat deworming is using sheep dose rates. Goats metabolize drugs faster than sheep, which means they clear many anthelmintics from their system before the drug has had its full effect. Most dewormers used in goats were originally developed and licensed for sheep or cattle, and correct dose rates for goats have rarely been experimentally determined.9Helminthologia. Anthelmintic resistance in parasites of small ruminants: sheep versus goats A pharmacokinetic comparison of six different anthelmintics across sheep, goats, and cattle confirmed that you cannot assume drugs behave the same across species. While some drugs showed similar blood-level profiles between sheep and goats, others did not, and none behaved the same in all three species.10PubMed. Pharmacokinetic comparison of six anthelmintics in sheep, goats, and cattle
In practice, this means goats typically need higher doses of benzimidazoles and macrocyclic lactones than sheep do, and the drugs should be given orally rather than by injection when possible to maximize gut exposure. Your veterinarian can advise on species-appropriate dosing. Underdosing does not just fail to kill worms; it selectively breeds for resistant worms by exposing them to a sub-lethal drug concentration.
When a Goat Is Too Anemic for Deworming Alone
A goat with a packed cell volume below about 12% is in a medical emergency. At that point, killing the worms does not solve the immediate crisis, because the goat has already lost so much blood that its organs are struggling for oxygen. One case report described a goat that arrived recumbent with pale membranes, a racing heart, and rapid breathing. Its PCV was 9.7%. The cause was confirmed as haemonchosis, and the animal required an emergency whole blood transfusion from a compatible donor goat in addition to deworming.11Romanian Journal of Veterinary Sciences. Whole Blood Transfusion in a Goat with Severe Haemonchosis
Blood transfusion in goats is not common, but it is sometimes the only option for severely anemic animals. The donor should ideally be from the same herd and healthy. The procedure buys time for the goat’s bone marrow to ramp up red blood cell production while the dewormer handles the worms. Supportive care during this phase typically includes keeping the goat calm, warm, and well hydrated, with easy access to high-quality forage and fresh water.
A product called Red Cell, a liquid iron and vitamin supplement marketed for livestock, is sometimes given alongside deworming in the hope of speeding recovery. However, a controlled study in sheep and goats found that a single dose of Red Cell did not alleviate anemia from gastrointestinal nematodes and did not improve the efficacy of anthelmintic treatment.12ScienceDirect (Small Ruminant Research). Determining the efficacy of Red Cell® in combination with anthelmintics against gastrointestinal nematode parasitism in sheep and goats The iron and B-vitamins in these supplements are not useless in principle, but they are not a shortcut to recovery when the anemia is severe.
Nutritional Support That Actually Helps
What does help recovery, and what helps goats resist worm infections in the first place, is good nutrition, particularly protein. A study on West African Dwarf goats infected with H. contortus found that animals on a high-protein diet took longer to develop detectable worm egg shedding, gained more weight during pregnancy, and had better kidding outcomes than goats on a low-protein diet.13PubMed. The effect of dietary protein on the productivity of West African Dwarf (WAD) goats infected with Haemonchus contortus In other words, protein does not just help goats recover from worms; it helps them fight off infections before they become severe. Supplementation with rumen-protected protein (protein formulated to bypass rumen digestion and be absorbed in the intestine) went even further, reducing the egg-laying output of adult female worms even when it did not reduce total worm numbers.14Scientific Reports. Supplementation with rumen-protected proteins induces resistance to Haemonchus contortus in goats Fewer eggs shed on pasture means fewer infective larvae for the rest of the herd.
Mineral nutrition matters too, especially for young kids. Goat kids raised indoors on milk alone can become iron-deficient because goat milk is low in iron. In one study, kids given 150 mg of iron dextran by injection had significantly higher hemoglobin levels at one month of age compared to untreated controls, over half of which fell below the normal reference range.15PubMed Central. Anaemia in Lambs and Kids Reared Indoors on Maternal Milk and the Impact of Iron Supplementation on Haemoglobin Levels and Growth Rates Cobalt deficiency is another overlooked cause of anemia in goats. Rumen microbes convert cobalt into vitamin B12, which is essential for red blood cell production. When Omani goats were raised on cobalt-deficient diets, they developed pale membranes, declining red blood cell counts, and poor growth within a few months.16PubMed. Effects of low concentrations of dietary cobalt on liveweight gains, haematology, serum vitamin B(12) and biochemistry of Omani goats Providing a goat-specific mineral mix that includes iron, cobalt, and copper is a straightforward way to prevent these nutritional gaps from compounding a worm problem.
Alternatives to Chemical Dewormers
Given how widespread drug resistance has become, several non-chemical approaches have been studied for their ability to reduce worm burdens in goats. None of them fully replaces deworming in an acute infection, but several have enough evidence behind them to be useful as part of an integrated strategy.
Copper Oxide Wire Particles
Copper oxide wire particles (COWP), given as a bolus, release copper slowly in the abomasum and have a direct toxic effect on H. contortus. In one trial with indigenous South African goats, COWP boluses reduced established worm burdens by over 90%.17PubMed Central. The potential to control Haemonchus contortus in indigenous South African goats with copper oxide wire particles When used as a mid-summer tactical treatment alongside FAMACHA-guided levamisole drenching, COWP reduced fecal egg counts by about 89%.18PubMed Central. Tactical treatment with copper oxide wire particles and symptomatic levamisole treatment using the FAMACHA(©) system in indigenous goats in South Africa The catch is that the effect does not last long. A persistence study found that the worm-reducing benefit peaked within the first week and was largely gone by four weeks.19PubMed Central. Persistence of the efficacy of copper oxide wire particles against Haemonchus contortus in grazing South African goats COWP also carries a copper toxicity risk, especially in sheep (goats tolerate copper better), so dosing must be precise and based on veterinary guidance.
Sericea Lespedeza
Sericea lespedeza (SL) is a tannin-rich legume that has shown consistent anti-parasitic effects in goats across multiple studies. The condensed tannins in the plant appear to act directly on worm cuticles. When researchers examined adult H. contortus recovered from SL-fed goats, the worms showed shrunken, damaged outer surfaces compared to worms from control animals.20PubMed. Effect of sericea lespedeza leaf meal pellets on adult female Haemonchus contortus in goats In a dose-titration study, goats fed SL hay at 75% of their diet had roughly 92% lower fecal egg counts and fewer abomasal worms than controls by day 42, and their packed cell volumes trended higher, suggesting less blood loss.21PubMed. Efficacy of sericea lespedeza hay as a natural dewormer in goats: dose titration study Infected goat kids fed SL-based diets also gained more weight per day than those on conventional bermudagrass hay, averaging about 104 grams per day versus roughly 76 grams per day.22Journal of Animal Science. The effects of feeding sericea lespedeza hay on growth rate of goats naturally infected with gastrointestinal nematodes
Sericea lespedeza is not available everywhere and has to make up a large fraction of the diet (at least 50%) to produce meaningful effects. Where it grows or can be sourced as pellets, it is a genuinely useful tool, especially as a maintenance strategy between deworming events.
Biological Control With Nematode-Trapping Fungi
The fungus Duddingtonia flagrans survives passage through the goat’s gut and then traps and kills worm larvae in the feces before they can develop into the infective stage that contaminates pasture. In a trial in semi-arid northeastern Brazil, goats receiving D. flagrans pellets twice a week had lower egg counts, higher packed cell volumes, and greater weight gains than a group treated with moxidectin and an untreated control group.23PubMed. Biological control of goat gastrointestinal helminthiasis by Duddingtonia flagrans in a semi-arid region of the northeastern Brazil A commercial product based on this fungus (BioWorma) exists, though availability varies by region. The fungus does not kill worms inside the goat; it breaks the reinfection cycle on pasture.
Pasture Management to Break the Worm Cycle
No deworming program will hold up if goats keep reinfecting themselves on contaminated pasture. H. contortus completes its life cycle in about three to four weeks under warm, moist conditions, but eggs shed in feces can hatch and develop into infective larvae in as little as four to five days. Rotational grazing takes advantage of this timing. Research at Langston University found that moving goats to a new pasture every five days was enough to escape significant parasite pickup during the summer.24NCAT Sustainable Agriculture Program (ATTRA). Tools for Managing Internal Parasites in Small Ruminants: Pasture Management
A few other pasture practices reduce larval exposure. Keeping goats off very short grass helps because infective larvae concentrate in the first inch or two of vegetation, especially in morning dew. Multi-species grazing with cattle or horses can also help, since those animals pick up H. contortus larvae without becoming infected (cattle have their own Haemonchus species, but the sheep and goat species generally does not establish well in them). Resting a pasture for several weeks during hot, dry weather kills off many larvae through desiccation, though in humid climates the larvae are far more persistent.
Monitoring Recovery After Treatment
Once you have dewormed an anemic goat, you need to confirm two things: that the drug worked, and that the goat is actually recovering. A fecal egg count 10 to 14 days after treatment tells you whether the worms were killed. If egg counts have not dropped substantially, the dewormer failed and you need to switch drug classes or consult your veterinarian about combination treatments.
For the goat itself, FAMACHA scores should improve within two to three weeks as red blood cell production catches up. The goat should become more active, eat more readily, and start regaining condition. If mucous membranes remain pale despite a confirmed drop in egg counts, consider nutritional anemia or a concurrent disease like anaplasmosis. A PCV check through your vet gives a more objective measure than eyeballing membranes if you are unsure. Pregnant and lactating does deserve extra attention because their immune systems are naturally suppressed around kidding, leaving them more vulnerable to heavy worm loads at the worst possible time.
Breeding for Worm Resistance
Some goat breeds are naturally more resistant to gastrointestinal worms than others. The Nigerian West African Dwarf goat, for example, shows a striking ability to resist both trypanosomiasis and nematode infections, a trait researchers believe is genetically based and mediated through the immune system.25PubMed Central. The unique resistance and resilience of the Nigerian West African Dwarf goat to gastrointestinal nematode infections In theory, breeding from the most resistant animals in a herd and selecting against the most susceptible ones could reduce overall reliance on dewormers over generations.
The genetics are not straightforward, though. Heritability estimates for fecal egg count in Alpine and Saanen dairy goats were low, around 0.07, meaning that individual variation in worm egg output is mostly driven by environment and management rather than genetics. Heritability of FAMACHA score and packed cell volume were somewhat higher at about 0.22. Perhaps more concerning for dairy operations, the genetic correlation between fecal egg count and milk yield was moderately positive, at 0.49, suggesting that selecting for higher milk production could inadvertently select for greater susceptibility to worms.26PubMed Central. The genetic basis for the selection of dairy goats with enhanced resistance to gastrointestinal nematodes For most small-scale goat keepers, deliberate genetic selection for parasite resistance is a slow, long-term project rather than a quick fix. But keeping records of which animals consistently score well on FAMACHA and which always seem to need treatment is a reasonable starting point for culling and breeding decisions.
Targeted Selective Treatment as a Long-Term Strategy
The thread running through all of this is that blanket deworming of every goat on a fixed schedule is counterproductive. It drives resistance, eliminates refugia (the population of drug-susceptible worms that compete with resistant ones), and gives a false sense of security. The alternative, targeted selective treatment, means treating only the animals that need it based on FAMACHA scores, body condition, and fecal egg counts. Studies across very different settings, from Greek dairy goats to tropical herds in Mexico, have consistently found that this approach reduces the total number of treatments administered while maintaining similar levels of production and parasite control.27PubMed. The use of targeted selective treatments against gastrointestinal nematodes in milking sheep and goats in Greece based on parasitological and performance criteria On a farm where resistant worm populations already exist and nutrition is poor, combining FAMACHA-guided treatments with body condition scoring and periodic fecal egg counts gives the best chance of stretching the useful life of the dewormers that still work.28Small Ruminant Research. Targeted treatment strategies for the control of gastrointestinal nematodes in a goat flock with anthelmintic resistant worm populations and poor nutrition
If you are dealing with an anemic goat right now, the immediate steps are clear: check FAMACHA, deworm with a product you have confirmed works on your farm, provide supportive nutrition, and get veterinary help if the PCV is dangerously low. But the long game matters just as much. Rotating pastures, feeding well, treating selectively, and keeping records of which goats need the most help are what keep anemia from becoming a recurring crisis instead of an occasional problem.