False positives can occasionally occur; CAHFS lab data suggests the false positive rate is less than five percent (<5%) of all positive cultures read by the lab. When false positives do occur, it is most likely due to the presence of a fecal trichomonad. Fecal trichs are routinely detected in young, group-raised virgin bulls as well as in mature breeding bulls.  If a virgin bull cultures positive, it is more likely to be a NTfT (non T. foetus trichomonad or fecal trich).

Polymerase Chain Reaction (PCR) can confirm culture results. PCR confirmation is recommended, but not required, for herds diagnosed with trichomonosis for the first time or if positive culture results are obtained from virgin bull samples. Specific PCR primers exist to differentiate Tritrichomonas foetus from fecal trichomonads. PCR testing can be done through CAHFS laboratories.

Three genera, with multiple species, make up the majority of trichomonads found in cattle: Tritrichomonas, Tetratrichomonas, and Pentatrichomonas. Within these categories, only one species of Tritrichomonas (Tritrichomonas foetus), many species of Tetratrichomonads, and one species of Pentatrichomonas (Pentatrichomonas hominis) are routinely detected in cattle. Tritrichomonas foetus is the only one of these protozoa that causes trichomonosis.

The veterinarian approved for trichomonosis sampling that collects the samples, is expected and required to report all positive and negative test results to CDFA. Positive tests must be reported within two days of the final lab reading date, and negative tests must be reported within 30 days.

Veterinarians submitting samples to CAHFS laboratories for reading should submit the top three copies of the Trichomonosis Test Report Form (AHB 76-199) to the lab with samples. CAHFS will report results directly to the appropriate Animal Health Branch District Office and return the owner and veterinarian copies to the submitting veterinarian.

However, according to the California Food and Agriculture Code of Regulations, section 9101, any licensed veterinarian, any person operating a diagnostic laboratory, or any person who has been informed, recognizes or should recognize, by virtue of education, experience, or occupation, that any animal or animal product is or may be affected by, has been exposed to, or may be transmitting or carrying any condition specified in the "List of Reportable Conditions for Animals and Animal Products," shall report to the department all known information required by the department within the time specified in the "List of Reportable Conditions for Animals and Animal Products."

False positive results will occasionally occur. Fecal trichomonads will grow in Tritrichomonas foetus culture media and can be mistaken for T. foetus . This situation is most likely when young, group–raised virgin bulls test positive on culture for T. foetus .

The animal owner or testing veterinarian can request culture results be confirmed by Polymerase Chain Reaction (PCR). Specific PCR primers exist to differentiate Tritrichomonas foetus from fecal trichomonads. PCR testing can be done through CAHFS laboratories. If the sample is negative for T. foetus and positive for other trichomonads, the bull will be released from quarantine.