Bovine trichomoniasisin beef cattle in Wyoming, USA

Transcription

1 Bovine trichomoniasisin beef cattle in Wyoming, USA Chaoqun Yao Department of Biomedical Sciences and One Health Center for Zoonosesand Tropical Veterinary Medicine Ross University School of Veterinary Medicine Basseterre, St. Kitts, West Indies 09/24/2014

2 Bovine trichomoniasis Prevalence in bulls Infection in females with abortion Risk factors associated with positive herds

3 Reproductive diseases of cattle Disease Vibriosis Leptospirosis Trichomoniasis Brucellosis Causative agent Campylobacter fetus Leptospira pomona Tritrichomonas foetus Brucella abortus GA_01.png Public Health Image Library

4 Tritrichomonas foetus Wood, 2009

5 Life cycle and transmission Tropohozoite Pseudocyst Mariante et al., 2004 Bulls: long term carriers Heifers and cows: Self-clear Up to 95% transmission rate

6 World distribution of bovine trichomoniasis

7 Current control strategies Animal selection Testing (Regulation) Vaccination Control No drugs approved

8 States with trichomoniasis programs

9 Prevalence in bulls Data Wyoming State Veterinary Laboratory (WSVL) and Wyoming Livestock Board between January 1, 1997 and December 31, 2010 Testing for T. foetus culture in Diamond s medium & PCR to amplify a 347bp fragment of 5.8S ribosomal RNA and the internal transcribed spacer region using primer pairs TFR3 and TFR4 (FelleisenRS et al., J ClinMicrobiol36: 513)

10 Prevalence in Wyoming beef cattle bull Yao et al., 2011 JBP 2:117

11 Herd prevalence ( ) Herd prevalence (%) Yao et al., 2011 JBP 2:117

12 Expansion of geographic distribution Yao et al., 2011 JBP 2:117

13 Infection in females with abortion Data Wyoming State Veterinary Laboratory (WSVL) between January 1, 2000 and December 31, 2010 Testing for T. foetus culture in Diamond s medium & PCR to amplify a 347bp fragment of 5.8S ribosomal RNA and the internal transcribed spacer region using primer pairs TFR3 and TFR4 (FelleisenRS et al., J ClinMicrobiol36: 513)

14 Testing in beef cows/heifers in Wyoming with abortion Year Ntotof Ntotof bull PCR Ntotof Culture Ntotof PCR Ntotof Culture Ntotof fetus accessions samples cows/heifers (Npos) cows/heifers (Npos) fetus (Npos) (Npos) (0) (2) (7) 0 1 (0) (0) 0 1 (0) (0) 0 1 (0) (0) (0) 7 (0) 2 (0) 2 (0) (0) 2 (0) 3 (0) 1 (1)# (0)* 2 (0) 2 (0) 2 (0) (0) 14 (0) 3 (0) 4 (0) Total (0) 79 (9) 10 (0) 12 (1)

15 Testing results for T. foetus among samples collected in Wyoming from the genital tract of cows/heifers with abortion and aborted fetuses Sample Npos Ntot %pos Aborted fetus Placenta Cows/heifers Uterus Vagina Cervix total

16 Risk factors associated with positive herds Aim To identify risk factors associated with herds infected with T. foetusin Wyoming beef cattle.

17 Study design Producer Education, income, trich knowledge etc. Study Population: All beef cattle herds Herd Size, bull age, breeding source, method, vaccination, testing etc. Allotment Type, neighboring herds, fencing status etc.

18 Survey conduction WSVL Design the questionnaire Return the questionnaire USDA NASS Send out the questionnaires Complete, send back the survey Producers Confidential

19 Proportion of respondents Total: 5,498 4,210; 76% 1,243; 23% 45; 1% Respond by mail Respond by phone call No respond Response proportion 23.4% Valid respond: 863 Invalid respond: 425 Unanswered form Steers only No cattle

20 Analytical methods Software Microsoft office Excel IBM SPSS19 SISA (online tool) Quality control Statistical method Data confirmation Refinement Exclusion of unqualified data Frequency analysis Pearson s chi-square Fisher s exact test

21 Feedback Feedback by geographic regions Feedback by herd size Percenta age (%) Census Survey Percen ntage (%) Census Survey Beef cow number per herd Geographic region (χ 2 =0.769, p>0.94) (χ 2 =7.860, p<0.05) JinY et al., 2014 JMM 63: Represents bigger sized herds (cow number 50)

22 Producer s awareness of bovine trichomoniasis % Percentage (%) % 24.2% 7.6% 0 Much knowledge Moderate Slightly familiar No knowledge JinY et al., 2014 JMM 63:

23 Trichomoniasistesting Trichomoniasis test 25.1% 2.4% 72.4% No Yes NA Reasons for trichomoniasis testing Using open or public allotments 304 negative, 8 positive 9.6% 27.1% 22.8% 34.1% Private transcation for reproductive purpose Concerns of neighbor positive or untested herds Management strategy 6.4% Others, unknown JinY et al., 2014 JMM 63:

24 T. foetusvaccination 17.6% 11.1% No Yes 71.3% NA JinY et al., 2014 JMM 63:

25 Average bull age % 80.0 Percentage (% %) % 46.0% Bull age at purchase Bull average age % 4.1% 1.1%.1%.2% 1.3% 1.2% unknown Bulls age JinY et al., 2014 JMM 63:

26 Breeding source Breeding method 2.1% 83.2% 14.7% Percentage (%) Artificial insemination Live cover Both Consideration of AI 39.6% 60.4% No Yes JinY et al., 2014 JMM 63:

27 Allotment type 11.4% 6.5% 24.3% 57.9% Family owned Rented privately owned Open/public Others JinY et al., 2014 JMM 63:

28 Fencing Time for get broken fences fixed 53.3% Broken fences 46.7% No Yes 82.7% 9.4% 1.3% 2.2% 4.4% Within a week Within a month Within three months Within one breeding season JinY et al., 2014 JMM 63:

29 Risk factors associated with bovine trichomoniasis Neighboring a positive herd(s) Using public allotment Comingling with neighbor herd(s) Elapsed time to fix broken fence(s) p= OR=18.3 ( ) p=0.003 OR=2.9 ( ) p=0.026 OR> p=0.078 OR=4.3 ( ) JinY et al., 2014 JMM 63:

30 Herd sizes and infection chance Prevalen nce (%) Prevalen nce (%) < Bull number per herd Cow number per herd χ 2 = 1.834, p=0.18 χ 2 = 1.266, p=0.30 JinY et al., 2014 JMM 63:

31 Conclusion Build good fences Check and fix fences regularly Allotment management Prevent comingling with other herds Use private allotments JinY et al., 2014 JMM 63:

32 JinY et al., 2014 JMM 63: A comprehensive approach to control and eradicate bovine trichomoniasis

33 Acknowledgment University of Wyoming: Yinzhu Jin Mark R. Davidson Brant Schumaker Katherine D. Bardsley Ross University School of Veterinary Medicine A. Lee Willingham