Fecal flotation exploits the specific gravity difference between parasite ova and flotation solution. Ova float to the surface while fecal debris sinks. Upload fecal flotation images to Fecal Analysis AI for educational parasite identification.
Use 2–5 grams of fresh feces (or from rectum); refrigerate if delay exceeds a few hours.
Mix feces with flotation solution (sugar solution SG 1.25–1.27, or sodium nitrate) to create a slurry. Strain through cheesecloth or a fecal strainer to remove coarse debris. Pour into a flotation vial, fill to create a positive meniscus, place coverslip on top, and allow 10–15 minutes for ova to rise. Transfer coverslip to slide and examine under 10× and 40× objectives.
Ascarids (Roundworms): Toxocara canis and T. cati ova are spherical, 75–90 µm, with a thick, pitted shell and dark interior. Most common in puppies and kittens. Zoonotic—advise hygiene, especially with children.
Hookworms: Ancylostoma and Uncinaria ova are oval, 55–75 µm, thin-shelled, with 4–8 cell morula. Cause anemia in young animals. Larval penetration is zoonotic (cutaneous larva migrans).
Whipworms: Trichuris vulpis ova are lemon-shaped, 70–90 µm, with bipolar plugs and thick, brown shell. Often in low numbers—examine multiple slides. Cause large bowel diarrhea.
Coccidia: Cystoisospora (formerly Isospora) oocysts are oval, 10–40 µm, with thin wall. Sporulated oocysts contain sporocysts. Common in young animals; self-limiting in immunocompetent adults but can cause severe diarrhea in neonates.
Giardia: Flotation may miss Giardia cysts—they are small (8–12 µm) and can collapse. Consider direct smear, zinc sulfate flotation (higher SG preserves cysts), or antigen testing. Cysts are oval with 2–4 nuclei visible.
| Parasite | Size | Shape | Key Feature |
|---|---|---|---|
| Toxocara | 75–90 µm | Round | Thick pitted shell |
| Hookworm | 55–75 µm | Oval | Thin shell, morula |
| Trichuris | 70–90 µm | Lemon | Bipolar plugs |
| Cystoisospora | 10–40 µm | Oval | Thin wall, sporocysts |
| Giardia | 8–12 µm | Oval | 2–4 nuclei |
Discuss parasite findings with the Parasitology Specialist. Puppies and kittens should be dewormed on a schedule regardless of fecal results due to prepatent periods and larval migration.
Positive fecal results warrant appropriate anthelmintic treatment. Annual fecal exams are recommended for adult pets. Zoonotic parasites require client education on hygiene and environmental decontamination.
- Use 2–5 g fresh feces; allow 10–15 min for ova to rise.
- Toxocara: 75–90 µm, round, thick pitted shell—zoonotic.
- Hookworm: 55–75 µm, oval, morula—cutaneous larva migrans risk.
- Trichuris: 70–90 µm, lemon-shaped, bipolar plugs.
- Giardia may be missed by flotation; consider zinc sulfate or antigen test.