Feline Tritrichomonas foetus (Tf) is a significant cause of infectious diarrhea in cats worldwide. Despite a high prevalence and lack of consistently effective drugs for treatment, the ways in which feline Tf causes disease are poorly understood. Using a previously developed model system to study this parasite outside of a live animal, Tf obtained from six naturally infected cats will be examined to determine the role of a specific protein, a cysteine protease (CP30), in causing disease. It is hypothesized that if CP30 is demonstrated to be present in feline Tf, inhibition of this protein may significantly prevent damage to the inner layer of the intestine in cats. Targeting potential inhibition of CP30 could lead to a future effective treatment of feline trichomonosis.