Question

Mycobacterium leprae grow well in

• A. Cat
• B. Dog
• C. Armadillo
• D. Platypus

Hint:

Think of the animal used in leprosy research because of its low body temperature.

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
Mycobacterium leprae, the bacterium that causes leprosy, cannot be grown on ordinary artificial culture media. We need the animal model in which it grows well.

Step 2: Key Formula or Approach:
M. leprae prefers cooler body temperatures, around 30 to 33 degrees Celsius, which is why it favours cool parts of the human body like skin, nerves and the nose. Any animal used for growing this bacterium must also have a body temperature in that low range, or must be used in a way that keeps the bacteria in cool tissue.

Step 3: Detailed Explanation:
Cats, dogs and platypuses have normal body temperatures too high for good M. leprae growth. The nine banded armadillo, however, has a naturally low body temperature (about 30 to 35 degrees Celsius) and a weak immune response against the organism, so it supports heavy multiplication of M. leprae throughout its body. This is why armadillos are used to produce large quantities of the bacterium for research and for making lepromin antigen. Mouse footpad inoculation is the other classic laboratory method, again because the footpad is a cooler site on the mouse's body.

Step 4: Final Answer:
Mycobacterium leprae grows well in the armadillo, option (C).