A Trichy Problem. Do you have trich? LIZ Y STEELE DVM. Getting a handle on trichomoniasis in beef herds in Florida

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1 A Trichy Problem Getting a handle on trichomoniasis in beef herds in Florida LIZ Y STEELE DVM Do you have trich?

2 Background Bovine Trichomoniasis Venereal disease of cattle caused by protozoan parasite Tritrichomonas foetus that causes increased abortion loss (>25%) Bulls are super spreaders able to infect multiple cows during coitus Electron micrograph of Tritrichomonas foetus. Image credit Parkinson TJ, England GCW, Arthur GH, Arthur's Veterinary Reproduction and Obstetrics, Saunders, 2001

3 Classic Management of Trich Identifying/Suspecting an infestation Unacceptable Numbers, Pyometra, late calf crop, or routine BSE PCR vs. Culture Culling Positive Bulls Vaccination of Cows & Bulls Culling Repetitively Open Cows Careful Purchase of Bulls and Cows Yearly Surveillance with your Veterinarian through BSE s Florida does not yet regulate intrastate movement of bulls in regards to Trich

4 Why is Trich a hot topic? Auburn University discovery of the pseudocyst Stumbling upon positive bulls converting to negative status Variability between interstate testing requirements Variation in pregnancy/calving/weaning percentages in Trich infested herds Variability in types tests and subsequent results

5 Gene Lollis Ranch Manager Dr. Betsey Boughton Director of Research Dr. Hilary Swain Executive Director Dr. Raoul Boughton Rangeland Scientist

6 Florida Beef Producers Providing opportunities to supply unvaccinated trich positive bulls

7 Team of Veterinarians Dr. John Yelvington Dr. John Crews Dr. Liz Steele Dr. Robert Gukich Dr. Kerry McGehee Dr. Owen Rae Dr. Mark Davis Dr. Max Ursik

8 InPouch

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11 CASE STUDY WHAT DID I STUMBLE UPON? October 2012 annual bull breeding soundness exam 9/108 Bulls with Positive Trichomonad Cultures No PCR done on initial cultures All Bulls have been vaccinated for T. foetus for at least 4 years Initial vaccination + booster at least 4 yrs previous to this event, then single annual booster TrichGuard (BI) vaccine used Adult Cows-No cows vaccinated for T. foetus

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13 CASE STUDY Second Test - ~3 weeks later 104 Bulls cultured 1 Positive Culture on a bull that was culture negative on 1 st test. Sample sent for PCR Confirmation Positive 9 previously culture positive T. foetus bulls are now culture negative

14 Case Study - Bulls Third Test 107 Bulls All Culture Negative Fourth Test 7 Previous Positive Cultures all negative on culture (3 of the original 10 bulls were out with a group of 78 cows) Fifth Test 10 Previous Culture positive bulls plus 5 cull bulls were tested - all culture negative 14 of these bulls are being tested monthly and have remained Culture and PCR negative

15 Case Study - Cows Group of 78 cows were commingled with the only PCR positive bull and two other Culture Positive bulls for ~60 days February 2013 all 78 were ultrasounded for pregnancy 52 Pregnant 26 Opens (66% Bred) 1 cow presented with uterine discharge that was culture positive for T. foetus and PCR confirmed

16 Case Study - Cows March pregnant 21 open (73% Bred) Cultured cows previously pregnant but open or if pregnant and had signs of inflammation 2 culture positives and 4 PCR T. foetus positives at Colorado of 9 sent for testing. April pregnant 25 open (68 %) Cultured cows previously pregnant but now open or if pregnant and had signs of inflammation Culture test all negative. PCR negative. May pregnant 25 Open 68% Bred Cultured 78 cows All Culture Negative PCR negative.

17 Temporal pattern of trich infection in cows repeated sampling of 78 head exposed to trich bulls Bulls Out # Pregnant % loss % Found Infected Feb March April May Jun Jul Aug Sep Oct Nov calving Post calving test for reservoir

18 Summary 10 Trich bulls became test NEGATIVE after vaccination and have remained that way for 11 months Evidence suggests these so called NEGATIVE bulls resulted in Trich being recovered from open cows they were exposed to.

19 Do we continue to cull positive bulls? Does the Trichgard vaccine clear infection in bulls? Does the vaccine mask a carrier status? If it does mask a carrier status, how does this impact state import/export rules? Does trich live further up the reproductive tract? Which single test should we recommend a producer use to screen his herd for trich? Do cows play a larger role in disease prevalence and persistence with in a herd?

20 THE TRICH PROJECT 1. Does vaccination of a T. foetus positive bull reduce the ability to successfully identify infection in a bull via culture or PCR? 2. If vaccination reduces the ability to successfully identify positive bulls, how long does their test negative status persist? 3. If the positive bull is vaccinated and becomes test negative, does the infection persist in the reproductive tract resulting in continued infection of the cow herd? 4. Observe the systemic IgG antibody titers to T. foetus

21 Started on March 3 rd with splitting the group and giving 1 st immunization Booster immunization on March 24 th 1 st collection April 21 st 2 nd collection May 19 th and monthly thereafter Trich Project Update Dr. John Crews

22 Studying Trich in Cows Is difficult because 1. Hard to recover organisms even in heavily infected cows 2. # of other factors involved in pregnancy rate and loss (nutrition, mineral status, other infectious diseases, weather, ect.)

23 I LOOK FORWARD TO GIVING A BETTER UPDATE IN MARCO!

24 What is going to change? More dificult Identifying/Suspecting an infestation Unacceptable Numbers, Pyometra, late calf crop, or routine BSE PCR vs. Culture Culling Positive Bulls Vaccination of Cows & Bulls Culling Repetitively Open Cows Careful Purchase of Bulls and Cows New testing methods Yearly Surveillance with your Veterinarian through BSE s Florida does not yet regulate intrastate movement of bulls in regards to Trich (THIS IS ABOUT TO CHANGE COUNTRYWIDE)

25 QUESTIONS?