Bovine tuberculosis progresses from initial infection, subclinical symptoms, to a severe disease state riddled with numerous lesions. Death may eventually result.

Step 1: Infection

• Bacteria enters respiratory system
• Engulfed by immune cells
• Carried to lymph nodes and throughout respiratory tract

Step 2: A silent danger 

• Symptoms often do not appear for long periods of time following infection (subclinical infection)

Step 3: Lesions!

• Development of numerous lesions on infected organs

Step 4: Death?

• Weakened, emaciated state
• May eventually result in death