Which test can help determine if an animal is infected with internal parasites?

The fecal flotation test is the most effective method for determining if an animal is infected with internal parasites, particularly gastrointestinal parasites such as roundworms, hookworms, and protozoa. This test works by examining a sample of the animal's feces to identify the presence of parasite eggs or cysts. The process involves mixing the fecal sample with a flotation solution that causes the lighter eggs and cysts to float to the surface, where they can be collected and examined under a microscope.

Unlike blood tests, which can indicate other health issues or the presence of certain parasites (such as heartworms), the fecal flotation specifically targets intestinal parasites, making it the preferred choice when assessing for these types of infections. X-rays, on the other hand, are primarily used for imaging bones and detecting certain masses, not for identifying parasitic infections. Urinalysis is valuable for assessing kidney function and urinary tract issues but does not relate directly to the presence of internal parasites. Therefore, the fecal flotation is the clear and specialized method for diagnosing infections caused by internal parasites in animals.