Ivan Leyva-Baca, DVM, PhD
Animal Health Product Applications at Thermo Fisher Scientific
What are the risk factors for Tritrichomonas foetus?
- Natural breeding – brings issues into the herd when the bulls are not tested properly
- Extensive range management – some regions of the world don't have proper fencing so there’s no way to buy bulls that can cover an entire herd of cows, so they need to share bulls (ejidos)
- No defined breeding season
- Neighbors with Trich infection – ensure proper fencing is in place
- Commingling of cattle
- Diagnostics with low sensitivity and specificity assays for Tritrichomonas foetus – can generate false positives and false negatives; request real-time PCR testing
- Age of bulls - 5+ years is a higher risk for Trich
- Implementing AI from untested bulls
What are the recommended control measures to manage Tritrichomonas foetus?
No treatment is available for Tritrichomonas foetus. While there's no vaccine for bulls, there is one available for cows. However, it often used to eradicate an existing infection from a herd rather than for prevention. Therefore, diagnostics are key to identification of positive bulls in order to remove them from the herd.
When comparing real-time PCR with the older testing method of culture, real-time PCR sensitivity and specificity is almost 100% for both, while culture is closer to 90%. Real-time PCR also offers additional capabilities like pooling samples to lower producer’s cost.
|
Culture OIE |
qPCR |
Number of samples to achieve good S&S |
3 |
1 |
Culture time |
7 days with daily |
25 hours and 1 qPCR |
Sensitivity |
92% |
100% |
Specificity |
92% |
99.5% |
USDA licensed |
NO |
Yes |
Increase reproducibility |
Moderate to Low |
Yes > 95% |
Cost |
More affordable |
Expensive, but it has pooling Capability (n=5) |
Elimination of Trich from Infected Herds
- Test all bulls 3 times with an interval of two weeks and cull all positive bulls
- Cull all unproductive cows that did not generate a calf at the end of the breeding season
- Allow for at least three estrus cycles for the infected cows to clean out the disease
- Use AI and proven negative bulls to avoid reintroduction for Trich into the herd
Prevention and Surveillance
- Biosecurity – ensure proper fencing is in place
- Replacements – use/purchase only tested negative bulls, virgin bulls and heifers from a reputable Trich-free ranch
- Reduce the bull battery to minimize the infection rate
