Step 1: Understanding the Concept:
Foot and Mouth Disease (FMD) is a highly contagious, economically devastating vesicular disease affecting cloven-hoofed domestic and wild animals.
Step 2: Detailed Explanation:
FMD is caused by Foot-and-Mouth Disease Virus (FMDV), an aphthovirus belonging to the family Picornaviridae.
It is characterized by fever and painful vesicles/blisters in the mouth, tongue, teats, and interdigital clefts of the feet, leading to lameness and dramatic milk production loss.
Step 3: Final Answer:
Hence, FMD is caused by a virus.