Gastrointestinal trichomonads in horses: occurrence and identification.

The research article examines the presence and identification of gastrointestinal trichomonads in horses and questions their role in causing equine diarrhea. The findings suggest that the particular trichomonad, Tritrichomonas equi, appears to be common in the horse’s intestinal system but likely not responsible for causing diarrhea.

Survey and Findings

• The researchers conducted a survey among 289 healthy horses, utilising a cultural examination of feces, which revealed trichomonads in 35% of the population (101 horses).
• In a separate group of 30 horses studied post-mortem, who demonstrated no symptoms of diarrhea prior to death, investigators found trichomonads in 37% of the cases (11 horses).
• In 4 out of these 11 cases, the researchers discovered trichomonad colonies ranging from 30,000 to 150,000 per milliliter in their cecal fluid, which is a part of the large intestine.

Experiment and Results

• Furthermore, the scientists attempted to induce diarrhea in 6 horses with varying levels of trichomonads in their system.
• Only in one horse was diarrhea successfully induced, where the fecal fluid contained 10,000 to 110,000 trichomonads per milliliter.

Identification of the Trichomonad and Role in Diarrhea

• The trichomonad in question was identified as Tritrichomonas equi.
• Despite its presence, the study suggests that this trichomonad is likely a normal part of the horse’s intestinal fauna as its prevalence did not seem to correlate directly with diarrhea.
• The role of Tritrichomonas equi as the cause of equine diarrhea was considered doubtful by the researchers.
• Their interpretation of the data led them to the conclusion that large numbers of Tritrichomonas equi found in diarrheic feces could be a response to the fluidic environment of the gastrointestinal tract rather than the cause of the same.