Vet-Approved 2025 Guide: Deworming Sheep and Goats 🐐🐑
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Vet-Approved 2025 Guide: Deworming Sheep and Goats 🐐🐑
Internal parasites—commonly called “worms”—are a leading health challenge for sheep and goats, especially in warm, humid regions. I'm Dr Duncan Houston, here to guide you through safe, effective deworming practices for 2025. We'll explore parasite biology, treatment options, strategic protocols, resistance testing, and management—all to protect your flock’s health and productivity. Let’s dive in! 🌱
Why Internal Parasites Matter
Gastrointestinal parasites in small ruminants live in the gut and steal nutrients, leading to decreased growth, milk production, and feed efficiency. While healthy animals may tolerate low worm burdens, high levels cause disease and even death. Goats, especially, are prone due to grazing habits and immune characteristics.
Signs of Subclinical versus Clinical Parasite Load
Subclinical infections slow growth and affect coat quality. Clinical signs—seen when burdens exceed resilience—include anorexia, diarrhea, anemia, edema, weakness, and sudden death in severe cases.
The Types of Parasites You’ll Encounter
Parasite species vary by region and host. Common culprits in the US include:
| Parasite | Signs |
|---|---|
| Barber pole worm (Haemonchus contortus) | Anemia, pale gums, edema, rapid decline |
| Whipworm (Trichuris) | Often asymptomatic; can cause diarrhea |
| Tapeworm (Moniezia) | Occasional weight loss or diarrhea in high numbers |
| Threadworm (Strongyloides) | Diarrhea, weakness in young stock |
| Threadneck worm (Nematodirus) | Severe watery diarrhea in lambs/kids |
| Nodular worm (Oesophagostomum) | Abdominal pain, diarrhea, weight loss |
| Bankrupt worm (Trichostrongylus) | Anemia, poor growth, edema |
| Coccidia (Eimeria) | Bloody diarrhea, colic, weight loss in young animals |
| Brown stomach worm (Ostertagia/Teladorsagia) | Poor condition, diarrhea, suboptimal growth |
| Cryptosporidium | Severe diarrhea in young kids/lambs |
These parasites often share symptoms—weight loss, poor coat, diarrhea—so fecal exams by your vet are essential to identify which worms are present before choosing treatment.
An Integrated Approach: Management + Deworming
Optimal deworming combines management and strategic drug use:
- Pasture rotation reduces re-infection
- Targeted deworming treats only those needing it
- Egg count monitoring prevents unnecessary treatments
- Strategic timing disrupts parasite lifecycle
Choosing Dewormers Wisely
Dewormers for small ruminants fall into three main classes:
| Class | Examples (Brands) | Resistance |
|---|---|---|
| Benzimidazoles (“white dewormers”) | Albendazole, Fenbendazole | High resistance in barber pole worms |
| Macrocyclic lactones | Ivermectin, Moxidectin | Ivermectin—high resistance; Moxidectin—moderate resistance |
| Membrane depolarizers | Levamisole, Pyrantel | Low–moderate resistance |
Because resistance is widespread—especially in Haemonchus—using a combination of classes provides broader control and reduces resistance development. Full doses of each class are essential.
Strategic Deworming Approaches
1. Salvage (Targeted) Deworming
Identifies high-shedders using systems like FAMACHA or fecal egg count, treating only those who need it. This minimizes drug use and delays resistance, though it requires frequent assessments (every 2 weeks).
2. Tactical Deworming
Treats all animals when fecal egg counts exceed thresholds—>1000 EPG in cold seasons, >2000 EPG when warm (humidity 50–80°F). This targets times when pasture contamination peaks, post-rain cycles.
3. Strategic Deworming
Schedules around physiological highs—e.g., deworming ewes/does 3 weeks pre-lambing/kidding, then every 3–4 weeks until offspring are 3 weeks old. This controls the pregnancy-related “periparturient egg rise,” but repeated use can foster resistance.
Managing Drug Resistance
Resistance can be tracked via:
- Fecal Egg Count Reduction Test (FECRT): measures reduction in worm eggs post-treatment—95%+ means effective.
- DrenchRite Larval Development Assay: lab test for resistance against multiple drug classes.
These tests help tailor effective protocols and reduce unnecessary treatments.
Smart Drenching Protocols
- Double cattle dose for benzimidazoles and macrocyclics in small ruminants (except levamisole/moxidectin)
- Oral administration via drenching guns to ensure full dose
- Always weigh your animals prior to dosing
- Use separate equipment per drug to avoid cross-contamination
2025 Innovations and Best Practices
- Genetic selection: breeding for parasite-resistant bloodlines
- Biological controls: nematode-trapping fungi as feed supplements
- Precision dosing: mobile scales and smart drench guns
- Pasture management: mixed-species grazing and rest rotations
Sample Protocol for a Humid Region Flock (2025)
- Spring: baseline fecal egg count
- Every 2 weeks: FAMACHA scoring during peak season; treat anemia–positive animals
- Warm season after rain: tactical treatment when counts spike
- Tactical drug rotation: alternate benzimidazole + levamisole vs. macrocyclics quarterly
- Pre-lamb/kid: strategic deworming with combination drench
- Fall cleanup deworm before cool-down
- Feeder monitoring: rotate pastures, sow clean forage, use multispecies grazing
Pasture & Management Practices
- Rotational grazing to break parasite cycles
- Mixed grazing with cattle—cattle don’t share the same worms
- Regular fecal tests every 8–12 weeks
- Cull high-shedders to protect the herd
When to Reach Out to Your Vet
- Signs of anemia despite treatment
- Poor response to deworming or high post-treatment egg counts
- Frequent illness in young lambs/kids
- No control despite strategic approach
Ask A Vet: Your Partner in Control 📲
Use the Ask A Vet app for:
- FAMACHA scoring help
- Fecal egg count guidance
- Protocol design and drug rotation plans
- Resistance testing guidance
Conclusion
Effective deworming in 2025 demands smart, integrated strategies involving pasture management, targeted treatments, and drug rotation. Backed by resistance testing and veterinary partnership, your sheep and goat health—and productivity—can thrive. Stay informed, stay strategic, and reach out through Ask A Vet for on-farm expert help anytime. 🐐💪
