The 5 Most Common Internal Parasites in Goats and Sheep: Identification, Symptoms, and Treatment
- Dr. Gaffud
- Sep 4
- 4 min read
Updated: Oct 20
Internal parasites in goats and sheep continue to pose a significant threat to herd health and profitability, particularly in pasture-based systems. These parasitic infections disrupt digestion, weaken the immune system, and reduce productivity. Understanding which internal parasites affect small ruminants most frequently helps veterinarians, farmers, and livestock managers implement timely and effective control strategies.
Table of Contents
Understanding Internal Parasites in Goats and Sheep
Internal parasites in goats and sheep are primarily transmitted through contaminated feed, water, and grazing pastures. Once ingested, these parasites lodge in the gastrointestinal or respiratory systems, impairing nutrient absorption, damaging organs, and reducing overall performance. Heavy infestations lead to poor weight gain, diarrhea, anemia, and, in severe cases, death.
Parasite control in goats and sheep relies on early detection, targeted deworming, pasture management, and nutritional support. A combination of veterinary diagnostics and sustainable interventions helps mitigate resistance to anthelmintic drugs.
Barber Pole Worm: A Deadly Internal Parasite in Goats and Sheep
Barber pole worm: Haemonchus contortus, a blood-feeding nematode residing in the abomasum of goats and sheep. This parasite ranks as the most dangerous internal parasite in goats and sheep. Its distinctive red-and-white striped appearance reflects its blood-engorged digestive tract. Heavy infestations result in rapid blood loss, leading to anemia, lethargy, bottle jaw (fluid swelling under the jaw), and sometimes sudden death.
Control strategy:
Use FAMACHA scoring. Monitor anemia levels by examining the lower eyelid.
Perform fecal egg counts. Quantify parasite burden and identify treatment thresholds.
Adopt targeted, selective treatment. Treat only animals with high egg counts or clinical signs of disease.
Implement rotational grazing. Disrupt the parasite life cycle by reducing larval exposure.
Coccidia: Protozoal Internal Parasites in Goats and Sheep
Coccidia: Microscopic protozoan parasites (e.g., Eimeria spp.) that infect the intestinal lining, especially in young animals.
Coccidiosis causes inflammation of the intestinal tract. Common symptoms include diarrhea (with or without blood), dehydration, weight loss, and decreased feed intake. Coccidiosis often spreads rapidly in overcrowded or unhygienic conditions.
Coccidiosis management:
Diagnose with fecal flotation. Identify oocysts under the microscope.
Treat with coccidiostats. Interrupt reproduction and reduce severity.
Maintain sanitation. Keep bedding dry and pens clean.
Reduce animal stress. Improve air flow and space allocation to minimize outbreaks.
Liver Flukes: Hepatic Internal Parasites in Goats and Sheep
Liver flukes: Flatworms such as Fasciola hepatica are transmitted through aquatic snails and infect the liver.
Liver flukes damage liver tissue, impair detoxification, and cause chronic wasting. Symptoms include jaundice, weight loss, decreased milk production, and poor body condition. In wet or poorly drained pastures, transmission risk increases significantly.
Liver fluke control:
Use sedimentation tests for diagnosis. Detect large fluke eggs in feces.
Administer flukicides. Target both juvenile and adult flukes.
Manage grazing. Avoid wet or marshy areas where snails thrive.
Improve drainage. Reduce snail habitat and transmission opportunities.
Tapeworms: Intestinal Internal Parasites in Goats and Sheep
Tapeworms attach to the intestinal lining and absorb nutrients. In light infections, clinical signs are minimal. In heavier infestations, signs include bloating, diarrhea, poor growth, and the presence of proglottids in the feces.
Tapeworm management:
Observe feces for segments. Look for white, rice-like proglottids.
Conduct fecal egg counts. Confirm presence through microscopic analysis.
Deworm using cestocidal agents. Eliminate adult tapeworms.
Promote pasture hygiene. Minimize contact with infected mite populations.
Lungworms: Respiratory Internal Parasites in Goats and Sheep
Lungworms: Nematodes such as Dictyocaulus filaria and Muellerius capillaris that inhabit the lungs. Respiratory internal parasites in goats and sheep cause coughing, wheezing, poor growth, and nasal discharge. Severe infections reduce feed efficiency and increase the risk of pneumonia in animals.
Lungworm intervention:
Diagnose using the Baermann technique. Detect larvae in feces.
Treat with anthelmintics. Choose medications effective against respiratory nematodes.
Prevent pasture overgrazing. Maintain grass height to limit exposure to larvae.
Practice rotational grazing. Break the parasite cycle and reduce larval density.
Holistic Care for Internal Parasites in Goats and Sheep
A sustainable approach to parasite management enhances resilience and reduces dependence on chemical treatments. Holistic care encompasses nutrition, genetics, environmental hygiene, and targeted treatment.
Holistic parasite control:
Provide balanced nutrition. Strengthen the immunity with a balanced intake of protein and essential minerals.
Use copper oxide wire particles (COWP). Offer targeted effects against barber pole worms.
Feed tannin-rich forages. Plants like sericea lespedeza help reduce worm burden.
Adopt rotational grazing. Lower reinfection risk through pasture rest.
Select resistant genetics. Incorporate animals with low fecal egg counts.
Maintain dry bedding and clean housing. Prevent fecal-oral transmission.
Quarantine new arrivals. Avoid introducing drug-resistant parasites.
Frequently Asked Questions About Internal Parasites in Goats and Sheep
How are internal parasites in goats and sheep diagnosed?
Veterinarians use fecal flotation, sedimentation, larval culture, and FAMACHA scoring to assess parasite burden and species.
What is an ideal deworming protocol?
Strategic and selective deworming based on fecal egg counts, species seasonality, and local resistance patterns improves outcomes and delays resistance.
Are these parasites transmissible to humans?
Most internal parasites in goats and sheep are not zoonotic in nature. Good hygiene and biosecurity help minimize any risk.
What role does fecal testing play in control programs?
Routine fecal analysis guides targeted treatment, monitors effectiveness, and helps detect anthelmintic resistance.
Are natural remedies effective against internal parasites?
When combined with proper nutrition, grazing management, and hygiene, natural interventions contribute to a sustainable control strategy.
Conclusion
Internal parasites in goats and sheep remain one of the most significant health concerns in small ruminant production. From the blood-feeding barber pole worm to the liver-damaging fluke, each parasite presents unique challenges requiring specific diagnostic and treatment protocols. Successful management depends on early identification, strategic deworming, rotational grazing, and holistic care that strengthens immunity and limits reinfection.
Sustainable parasite control safeguards flock health, supports productivity, and reduces economic losses. By adopting science-based strategies, livestock operations maintain resilient animals and ensure long-term profitability without relying solely on pharmaceuticals.
I showed this to my uncle who raises goats—he said it’s really accurate!