Internal Parasites (Worms): Causes, Symptoms, and Treatment
TL;DR: Internal parasites — roundworms, tapeworms, cecal worms — don’t kill gamefowl suddenly like fowl cholera or typhoid; they gradually siphon nutrients, causing weight loss even when the bird eats well. Treat with Wormal tablets (½ tablet at 8 weeks, 1 tablet for adults every 2 months), then Vitmin Pro 3 days after. Skip deworming a sick bird until it recovers.
What Are Internal Parasites?
Internal parasites, or worms, are organisms that live inside a chicken’s body — in the intestines, esophagus, or cecum. The three most common types in chickens are:
- Roundworms (Ascaridia galli) — the most common, found in the intestines
- Tapeworms (Raillietina) — flat and segmented, spread through insects
- Cecal worms (Heterakis gallinarum) — live in the cecum
Unlike fowl cholera or fowl typhoid and pullorum, which can kill a bird overnight, worms don’t kill immediately — they gradually siphon nutrients from your birds, causing weight loss even when the bird is eating well. See our guide to common gamefowl diseases for how they compare to other flock threats.
What Are the Symptoms of Worms in Chickens?
Weight loss despite eating well is the classic sign of worms — a chronic drag on condition rather than a sudden collapse.
- Weight loss despite eating well — this is the classic sign of worms
- Pale comb and wattles
- Decreased egg production
- Visible worms in droppings (in severe cases)
- Diarrhea, overall poor condition
Tip: You won’t always see worms in the droppings. Even if none are visible, if your bird is losing weight and has a pale comb, go ahead and deworm.
How Do You Treat Worms With Wormal Tablets?
Dose Wormal by bird age and size, then follow with a short recovery phase. This table sizes doses off typical gamefowl weight-for-age — a layer, native chicken, or broiler can weigh more or less than a gamefowl at the same age, so go by your bird’s actual weight and the product label rather than matching by age alone.
| Bird Age/Size | Dosage | Schedule |
|---|---|---|
| 8 weeks old | ½ tablet per bird | Administer orally (fasting not required) |
| Adult birds (stags, hens, breeders) | 1 tablet per bird | Every 2 months (regular maintenance) |
| Heavy infestation | 1 tablet per bird | Every month until the infestation clears |
How to Administer Wormal
- Get the correct dosage (½ or 1 tablet)
- Carefully open the bird’s beak
- Place the tablet at the back of the tongue
- Close the beak and hold briefly until the bird swallows
Recovery Phase
| Day | Supplement |
|---|---|
| 3 days after deworming | Vitmin Pro — 10g per gallon of water, daily |
What Is the Deworming Schedule?
A regular schedule prevents worm problems before they start, rather than treating a heavy infestation after the fact.
| Schedule | For Whom |
|---|---|
| Every 2 months | All adult birds — broodcocks, broodhens, stags, hens |
| Every month | If your farm has a history of heavy infestation |
| At 8 weeks old | All growing birds, first deworming |
For a fuller 8-day protocol that pairs deworming with a bacterial flush, see our deworming and bacterial flushing guide.
Pro tip: Log your deworming schedule in the FarmHub Health Hub so you get a reminder for the next deworming.
How Do You Prevent Worm Infestations?
Deworming on a fixed schedule, not waiting until you spot worms, is the single biggest prevention factor.
- Deworm on schedule — every 2 months, don’t skip it
- Keep the coop clean — remove droppings daily
- Avoid overcrowding — more birds in a small space means worms spread faster
- Replace the soil/sand in the coop regularly
What Are the Golden Rules of Deworming?
- Give Vitmin Pro after deworming — not at the same time. It’s for recovery support only; administer for 3 days after the treatment.
- Don’t deworm sick birds. Make sure the bird is healthy before deworming — a stressed or sick bird will have a harder time recovering.
- Isolate heavily infested birds from the healthy flock while treating.
- Follow a regular deworming schedule — every 2 months for adults. Don’t wait until you see worms before deworming.
- Clean the coop after deworming — remove droppings so the birds don’t get reinfected.
- Complete the full treatment even if the bird looks fine. Stopping early risks creating drug-resistant parasites.
- Prevention is better than treatment. Clean coop, dry sand, regular deworming, and proper vaccination.
Disclaimer: This guide is for reference purposes and is based on manufacturer product labels and published poultry health sources. Consult a veterinarian for severe or unusual cases. Observe the proper withdrawal period before consuming meat or eggs from treated birds.
Frequently Asked Questions
What are the most common internal parasites in gamefowl?
Roundworms (Ascaridia galli) are the most common, living in the intestines. Tapeworms (Raillietina) are flat and segmented and spread through insects. Cecal worms (Heterakis gallinarum) live in the cecum.
What is the classic sign of worms in gamefowl?
Weight loss despite eating well is the classic sign. A pale comb, decreased egg production, and diarrhea can also show up, though you will not always see worms in the droppings.
Do worms kill gamefowl as quickly as cholera or typhoid?
No. Unlike fowl cholera or fowl typhoid and pullorum, which can kill suddenly, worms do not kill immediately — they gradually siphon nutrients from the bird, causing a slow drag on weight and condition rather than an acute die-off.
How is Wormal tablet dosed?
Half a tablet per bird at 8 weeks old, 1 tablet per adult bird every 2 months for regular maintenance, or 1 tablet per bird every month during a heavy infestation until it clears.
How often should adult gamefowl be dewormed?
Every 2 months as regular maintenance. If your farm has a history of heavy infestation, deworm every month instead.
What should you give after deworming?
Vitmin Pro — 10g per gallon of water, daily, starting 3 days after deworming — for recovery support, not during the deworming itself.
Can you deworm a sick bird?
No. Make sure the bird is healthy before deworming — a stressed or sick bird will have a harder time recovering from the treatment.
How do you prevent worm infestations?
Deworm on schedule every 2 months, keep the coop clean by removing droppings daily, avoid overcrowding, and replace the coop soil or sand regularly.