Bovine Tuberculosis

Bovine Tuberculosis

What is the transmission mechanism behind bovine tuberculosis and how is it tested for?

Wild boar showing localized submandibular lymph node (a) and generalized lung (b) bovine tuberculosis lesion patterns (Risco, 2014).

Background

Knowledge

(OIE, 2009)

AN SC 200

Trisha Mead

Tuberculin Skin Test

What is bovine tuberculosis?

What are the symptoms of bovine tuberculosis and how is it treated?

• Contagious, zoonotic disease

Symptoms

• Caused by Mycobacterium bovis bacterium

• Similar to tuberculosis in humans

(CFIA, 2015)

(OIE, 2009)

Treatment

• Antibiotics
• Pre-emptive vaccines

Bovine tuberculosis and humans...

Unpopular in cattle...

• Costly
• Time consuming
• Interfere with eradication

(CDC, 2011)

An antigen is injected into the animal.

How is bovine tuberculosis diagnosed?

(de la Rua-Domenech, 2006)

How is bovine tuberculosis transmitted?

Live animals:

(OIE, 2009)

• Tuberculin skin test
• Blood tests for cellular immunity
• Cultured tissue sample

Mycobacterium bovis (Y tambe, 2007).

• Contact with infected animals
• Inhalation of aerosol droplets
• Contact with infected open wounds
• Ingestion of raw milk

(The Centre for Food Security and Public Health, 2009)

(OIE, 2009)

Post-mortem:

• Meat inspection
• Lymph nodes and tubercles

The immune response is measure. Swelling indicates a positive result.

(OIE, 2009)

The Bigger

Picture

(CFIA, 2015)

How is the government handling bovine tuberculosis?

*Federal reportable disease*

How has bovine tuberculosis affected the beef industry/producers?

The CFIA claims that the outbreak will not affect food safety.

References

Producer Concerns

• Quarantine will mar producer's reputation with buyers
• Sales will decrease

Producer Feelings

• Alienation,
• Lack of transparency, and
• Lack of communication by the CFIA

These issues are being resolved

(CBC, 2016)

Canadian Food Inspection Agency (CFIA). 2015. Bovine tuberculosis – Fact sheet. Accessed Feb. 2017. http://www.inspection.gc.ca/animals/terrestrial-animals/diseases

reportable/tuberculosis/factsheet/eng/1330208938232/1330209051950.

Canadian Food Inspection Agency (CFIA). 2017. Bovine tuberculosis (Bovine TB) investigation – Alberta and Saskatchewan. Accessed Feb. 2017. http://www.inspection.gc.ca

animals/terrestrialanimals/diseases/reportable/tuberculosis/investigation-alberta-and-saskatchewan/eng/1477438380160/1477438380659.

Canadian Food Inspection Agency (CFIA). n.d. Testing methods used to confirm bovine TB (species and strain). Alberta Beef Producers. Accessed Feb. 2017. http:/

albertabeef.org/uploads/additionaltestinginfopdf-618.pdf.

CBC. 2016. Bovine TB quarantine marred by lack of transparency, Alberta rancher tells Ottawa MPs. Accessed Feb. 2017. http://www.cbc.ca/news/canada/calgary/cattle-bovine

tb-quarantinecompensation-communication-osadczuk-ottawa-alberta-1.3862623.

Centre for Disease Control (CDC). 2011. Mycobacterium bovis (Bovine tuberculosis) in humans. Accessed Feb. 2017. https://www.cdc.gov/tb/publications/factsheets/general

mbovis.pdf.

The Centre for Food Security and Public Health. 2009. Bovine tuberculosis. Accessed Feb. 2017. http://www.cfsph.iastate.edu/Factsheets/pdfs/bovine_tuberculosis.pdf.

Cotter, J. 2017. Food safety agency to trace source of Alberta’s bovine tuberculosis outbreak. CBC. Accessed Feb. 2017. http://www.cbc.ca/news/canada/calgary/bovine

tuberculosis-outbreakalberta-1.3967055.

de la Rua-Domenech, Ricardo. 2006. Human mycobacterium bovis infection in the United Kingdom: Incidence, risks, control measures and review of the zoonotic aspects of

bovine tuberculosis. Tuberculosis. 86:77–109.

Nishi, J. S., T. Shury, and B. T. Elkin. 2006. Wildlife reservoirs for bovine tuberculosis (Mycobacterium bovis) in Canada: Strategies for management and research. Tuberculosis.

112:325–33

Risco, David. Lesions consistent with bovine tuberculosis on the lower jaw and lung of a wild boar. 2014. Wikipedia. Web. 5 Feb. 2017.

World Organisation for Animal Health (OIE). 2009. Bovine tuberculosis. Accessed Feb. 2017. https://web.oie.int/eng/normes/MMANUAL/2008/pdf/2.04.07_BOVINE_TB.pdf.

Y tambe. Microscopic image of the bacille calmette-guerin (BCG, Japan strain). Ziehl neelsen staining. Magnification: 1,000. 2007. Wikipedia. Web. 6 Mar. 2017.

Any artistically questionable illustrations are done by me.

The remaining photographs are licensed under Wikipedia Creative Commons and are free of copyright restrictions.

My illustration of the external appearance of a cow infected with Mycobacterium bovis.