Inspectors look for exterior signs of disease which can affect the animal and humans. Cattle must be killed. Meat is unusable. Disease comes from a mosquito. It is extremely contagious from one animal to another.
Humans can get the disease from eating infected meats.
There is a vaccination to prevent the disease. Other diseases are Rocky Mountain Fever, Rabies, VD, etc. Animals are constantly being inoculated, washed, sanitized, etc. to prevent diseases. It must be alive, unmarred, alert and have no broken bones. Workers must go for health check-ups every six months.