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1 Environmental distribution of M. paratuberculosis on cow-calf farms with clinical Johne’s disease in Western Canada Dale Douma DVM Western College of.

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Presentation on theme: "1 Environmental distribution of M. paratuberculosis on cow-calf farms with clinical Johne’s disease in Western Canada Dale Douma DVM Western College of."— Presentation transcript:

1 1 Environmental distribution of M. paratuberculosis on cow-calf farms with clinical Johne’s disease in Western Canada Dale Douma DVM Western College of Veterinary Medicine

2 2 Outline Introduction to the Johne’s Disease Introduction to the Johne’s Disease Research Research Prevalence Study Prevalence Study Wildlife Study Wildlife Study Environment Study Environment Study Conclusions Conclusions

3 3 What is Johne’s disease? Chronic granulomatous enteritis of ruminants Chronic granulomatous enteritis of ruminants Signs include: Signs include: Profuse diarrhea Profuse diarrhea Severe weight loss Severe weight loss Altered lining of the intestine Altered lining of the intestine Thickened and corrugated mucosa Thickened and corrugated mucosa Caused by Mycobacterium paratuberculosis Caused by Mycobacterium paratuberculosis http://www.johnes.org

4 4 History of Johne’s Bacterial cause discovered by Dr. H. Johne and Dr. L. Frothingham in 1895 in Germany Bacterial cause discovered by Dr. H. Johne and Dr. L. Frothingham in 1895 in Germany Acid fast bacteria similar to M. avium and pathology similar to intestinal tuberculosis in cattle Acid fast bacteria similar to M. avium and pathology similar to intestinal tuberculosis in cattle First found in North America in 1908 First found in North America in 1908 http://www.johnes.org/history/index.html

5 5 M. paratuberculosis aka M. avium paratuberculosis “Map” aka M. avium paratuberculosis “Map” Virtually identical to M. avium genetically (>99%) Virtually identical to M. avium genetically (>99%) Behaves differently Behaves differently Mycobactin dependant for iron transport Mycobactin dependant for iron transport Slower growing Slower growing Primarily infects ruminants but not exclusively Primarily infects ruminants but not exclusively

6 6 M. paratuberculosis Small Gram-positive rod-shaped bacterium Small Gram-positive rod-shaped bacterium Acid Fast positive Acid Fast positive Tendency to clump together Tendency to clump together Waxy rough cell wall Waxy rough cell wall Can survive outside of host Can survive outside of host Replicates inside of macrophages Replicates inside of macrophages

7 7 Johne’s Disease Transmission Cycle: Pictures from: http://www.johnes.org

8 8 Why present at ADED? Cattle prevalence increasing Cattle prevalence increasing Host range expanding? Host range expanding? Other ruminants Other ruminants Non-ruminants Non-ruminants Primates Primates Zoonotic concern Zoonotic concern Crohn’s disease Crohn’s disease Positive association evident Positive association evident http://www.johnes.org/zoonotic/index.html

9 9 Research Objectives Determine the seroprevalence of Map in Canadian beef cow-calf herds Determine the seroprevalence of Map in Canadian beef cow-calf herds Survey wildlife present on cow-calf farms that may be infected with Map Survey wildlife present on cow-calf farms that may be infected with Map Characterize the distribution of Map within the environment of these cow-calf herds Characterize the distribution of Map within the environment of these cow-calf herds Evaluate the potential of using environmental sampling as a economical herd test Evaluate the potential of using environmental sampling as a economical herd test

10 10 Seroprevalence Study Production Limiting Disease Committee research project Production Limiting Disease Committee research project Collected 4778 serum samples from 179 cow- calf herds across Canada in 2003 Collected 4778 serum samples from 179 cow- calf herds across Canada in 2003 excluding Manitoba and Quebec excluding Manitoba and Quebec

11 11 Table 1. Summary of the results of cow and herd level seroprevalence by province. Animal Level Prevalence Herd Level Prevalence ( ≥ 2 pos.) Region No. of cows tested positive No. of cows tested Apparent Prevalence % (95%CI) No. of herds tested positive No. of herds tested Prevalence % (95%CI) Alberta78330.8% (0-1.7)2296.9% (0-16.3) British Columbia311960.3% (0-0.5)0440.0% Ontario1110371.1% (0-2.1)3407.5% (0-15.8) Saskatchewan58800.6% (0-1.1)1323.1% (0-9.3) Maritimes (NB,NS,PEI)118321.3% (0-2.6)2345.9% (0-13.9) Overall3747780.8% (0.4-1.1)81794.5% (1.4-7.5) Serologic results determined by Elisa testing using the optical density cutoff of 0.100 above the mean of two negative controls

12 12 Wildlife Survey Trapped wild rodents and birds on 6 cow-calf herds with clinical Johne’s disease Trapped wild rodents and birds on 6 cow-calf herds with clinical Johne’s disease 4 rounds of trapping 4 rounds of trapping One round every 3 months for one year One round every 3 months for one year

13 13 Wildlife Survey Results – all 4 rounds Results – all 4 rounds 202 Birds (sparrows, junco, swallows, etc) 202 Birds (sparrows, junco, swallows, etc) 236 Rodents (house mice, deer mice, RGS, etc) 236 Rodents (house mice, deer mice, RGS, etc) No positive samples No positive samples Birds and rodents appear to be non susceptible or unaffected by Map due to low exposure on cow-calf farms Birds and rodents appear to be non susceptible or unaffected by Map due to low exposure on cow-calf farms

14 14 Coyote Survey Part of tuberculosis study by Dr. Gary Wobeser and Dr. Cheryl Sangster Part of tuberculosis study by Dr. Gary Wobeser and Dr. Cheryl Sangster Lymph nodes collected from 82 trapped coyotes around Riding Mountain National Park and submitted for culture to the CFIA Lymph nodes collected from 82 trapped coyotes around Riding Mountain National Park and submitted for culture to the CFIA 0 positive for tuberculosis 0 positive for tuberculosis 3 positive for Map (3.7%; 95% CI 0-7.7) 3 positive for Map (3.7%; 95% CI 0-7.7) Significance Significance First report of Map cultured from multiple coyotes at one location First report of Map cultured from multiple coyotes at one location Further research required Further research required

15 15 Map of trapped coyote locations Blue – Map NegativeRed – Map Positive RMNP

16 16 Environmental Study Method Method Enrolled 27 herds with a history of clinical Johne’s disease Enrolled 27 herds with a history of clinical Johne’s disease Collected approx. 15 environmental samples per herd during the calving season Collected approx. 15 environmental samples per herd during the calving season Collected manure from up to 150 cattle per herd to estimate prevalence Collected manure from up to 150 cattle per herd to estimate prevalence Cultured in pools of 5 Cultured in pools of 5 Compared results of test methods Compared results of test methods

17 17 Environmental Study Results Results Water Samples Water Samples 26 biofilm samples, 54 samples from waterers, 21 dugout samples, and 13 farm drainage samples including creeks and rivers 26 biofilm samples, 54 samples from waterers, 21 dugout samples, and 13 farm drainage samples including creeks and rivers 0 culture positive for Map 0 culture positive for Map

18 18 Environmental Study 243 non-water environmental samples were collected 243 non-water environmental samples were collected 15 (6.2%) were positive for Map 15 (6.2%) were positive for Map chute systems: 4/26 (15.6%) chute systems: 4/26 (15.6%) outside cattle feeders: 3/21 (14.3%) outside cattle feeders: 3/21 (14.3%) inside cattle feeders: 2/21 (9.5%) inside cattle feeders: 2/21 (9.5%) mothering-up pens: 2/13 (15.4%) mothering-up pens: 2/13 (15.4%) bullpens : 1/7 (14.3%) bullpens : 1/7 (14.3%) turnout pens: 1/10 (10.0%) turnout pens: 1/10 (10.0%) calf shelters: 1/18 (5.6%) calf shelters: 1/18 (5.6%) calving pens: 1/26 (3.8%) calving pens: 1/26 (3.8%) No Map was detected in 101 samples from: pastures (24), hospital pens (19), manure storage areas (17), young stock pens (10), creep feeders (7), mineral supplements (4), calf pens (2), and other areas of owner concern (18). No Map was detected in 101 samples from: pastures (24), hospital pens (19), manure storage areas (17), young stock pens (10), creep feeders (7), mineral supplements (4), calf pens (2), and other areas of owner concern (18).

19 19 Environmental Study Results for Environmental Testing as a Herd Test Results for Environmental Testing as a Herd Test 8 of 27 (29.6%) herds had at least one positive environmental sample 8 of 27 (29.6%) herds had at least one positive environmental sample 17 of 27 (63.0%) herds had at least one positive fecal pool 17 of 27 (63.0%) herds had at least one positive fecal pool 2 of 27 (7.4%) herds were positive only on environmental sampling 2 of 27 (7.4%) herds were positive only on environmental sampling 9 of 27 (33.3%) herds were positive only with fecal pool cultures 9 of 27 (33.3%) herds were positive only with fecal pool cultures

20 20 In Conclusion At this time: At this time: Johne’s prevalence in cow-calf herds in Canada is relatively low Johne’s prevalence in cow-calf herds in Canada is relatively low Environmental contamination of Map on cow-calf farms is low Environmental contamination of Map on cow-calf farms is low The time to act is now The time to act is now Environmental sampling as done in this research study is not sensitive enough at this time to replace animal sampling Environmental sampling as done in this research study is not sensitive enough at this time to replace animal sampling

21 21 Thank you! Funding Agencies: Funding Agencies: Agriculture Development Fund of Saskatchewan Agriculture Development Fund of Saskatchewan Beef Cattle Research Council Beef Cattle Research Council Beef Development Fund of Saskatchewan Beef Development Fund of Saskatchewan Wildlife Health Fund Wildlife Health Fund Interprovincial Graduate Student Fellowship Interprovincial Graduate Student Fellowship


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