Whipworms (Trichuris vulpis)
Why they matter: A common GI parasite in U.S. dogs and can cause chronic large-bowel diarrhea.
How dogs get them: Ingesting eggs from contaminated environments (soil/yards). Eggs can persist in the environment for long periods.
Common signs: Intermittent diarrhea (often with mucus/blood), straining, weight loss—or none.
Diagnosis: Fecal testing; whipworms can be tricky to catch on a single sample, so repeat testing may be recommended.Treatment & prevention: Treatment often involves a schedule of doses over time plus prevention and environmental hygiene.