By Dr. Maral Rahmani
PoultryMed Veterinary Services
March 2025
Introduction
Small poultry flocks are susceptible to various intestinal worms, with the most common being roundworms, cecal worms, threadworms, and tapeworms. While a small number of worms typically do not cause harm, heavy infestations can lead to diarrhea, weight loss, anemia, decreased egg production, and other health issues. Since these symptoms are not specific to worm infections, microscopic examination of feces is necessary for accurate diagnosis.
How Do Poultry Get Infected?
Birds become infected by ingesting worm eggs from contaminated feed, water, litter, or soil. They can also acquire worms by consuming infected intermediate hosts such as earthworms, insects, and snails. Worm eggs are highly resistant to disinfectants and can survive in the environment for extended periods, increasing the risk of reinfection.
Deworming Strategies
Deworming can be done either routinely or only when a high worm burden is detected. Veterinary clinics and diagnostic labs can assess worm levels through fecal testing. The best deworming approach depends on factors such as flock size, housing conditions, and the history of worm infestations.
Fenbendazole is one of the approved dewormers for roundworms and cecal worms in chickens and turkeys in Canada and is available as medicated feed or a water-soluble formulation. When used according to label directions, no withdrawal period is required for eggs or meat. Off-label use requires a veterinarian’s prescription. Currently, no approved treatments exist for tapeworms in Canada. Consulting a veterinarian is essential for diagnosing and managing intestinal worms in poultry.
Important Considerations
- Overuse or improper dosing of dewormers can contribute to drug resistance, so routine fecal testing and targeted treatment are recommended.
- Since worm eggs can persist in the environment, implementing strong biosecurity measures, maintaining proper sanitation, and practicing pasture rotation can help reduce reinfection risks.
