Bovine Tuberculosis Epidemiology

Etiology of Bovine Tuberculosis

• Caused by Mycobacterium bovis and, to a lesser extent, Mycobacterium caprae

Epidemiology of Bovine Tuberculosis

• All age groups and species are susceptible to infection
• Infection is predominantly found in cattle and pigs
• Infected cattle are the main source of infection
• Wildlife reservoirs are important in some regions, making eradication of bovine tuberculosis challenging in some countries

Transmission of Bovine Tuberculosis

• Inhalation is the major method of transmission between cattle
• Pigs are primarily infected orally

Zoonosis and Human Infection

• Humans can be infected through consumption of unpasteurized dairy products
• Other routes of human infection include inhalation and direct contact

Clinical Findings of Bovine Tuberculosis

• Progressive emaciation
• Capricious appetite
• Fluctuating temperature
• Signs referable to localization, such as:
  • Respiratory disease
  • Pharyngeal obstruction
  • Reproductive disorder
  • Mastitis
• In pigs, the disease is subclinical, but tuberculous lesions may be found in cervical lymph nodes

Clinical Pathology of Bovine Tuberculosis

• Tuberculin testing:
  • Single intradermal test is the official test in most countries
  • Single intradermal comparative test for cattle suspected as false-positive reactors
• Interferon-gamma testing

Necropsy Findings of Bovine Tuberculosis

• Tuberculous granulomas may be found in any of the lymph nodes
• Generalized tuberculosis may be present

Diagnostic Confirmation of Bovine Tuberculosis

• Culture of the organism
• Identification by polymerase chain reaction (PCR) or other molecular techniques

Control of Bovine Tuberculosis

• Test and slaughter
• Most countries have official eradication programs

Etiology of Bovine Tuberculosis

• Caused by Mycobacterium bovis and, to a lesser extent, Mycobacterium caprae

Epidemiology of Bovine Tuberculosis

• All age groups and species are susceptible to infection
• Infection is predominantly found in cattle and pigs
• Infected cattle are the main source of infection
• Wildlife reservoirs are important in some regions, making eradication of bovine tuberculosis challenging in some countries

Transmission of Bovine Tuberculosis

• Inhalation is the major method of transmission between cattle
• Pigs are primarily infected orally

Zoonosis and Human Infection

• Humans can be infected through consumption of unpasteurized dairy products
• Other routes of human infection include inhalation and direct contact

Clinical Findings of Bovine Tuberculosis

• Progressive emaciation
• Capricious appetite
• Fluctuating temperature
• Signs referable to localization, such as:
  • Respiratory disease
  • Pharyngeal obstruction
  • Reproductive disorder
  • Mastitis
• In pigs, the disease is subclinical, but tuberculous lesions may be found in cervical lymph nodes

Clinical Pathology of Bovine Tuberculosis

• Tuberculin testing:
  • Single intradermal test is the official test in most countries
  • Single intradermal comparative test for cattle suspected as false-positive reactors
• Interferon-gamma testing

Necropsy Findings of Bovine Tuberculosis

• Tuberculous granulomas may be found in any of the lymph nodes
• Generalized tuberculosis may be present

Diagnostic Confirmation of Bovine Tuberculosis

• Culture of the organism
• Identification by polymerase chain reaction (PCR) or other molecular techniques

Control of Bovine Tuberculosis

• Test and slaughter
• Most countries have official eradication programs

This quiz covers the etiology and epidemiology of bovine tuberculosis, including the main sources of infection, transmission methods, and susceptible species.