The normal body temperature of the cow is 36.7°C - 39.3°C.
Body temperatures below 36.7°C constitute hypothermia, and temperatures above 39.3°C constitute hyperthermia (fever).
Fever is usually an indication of inflammation within the body. Inflammation can be a result of tissue damage (e.g. trauma, allergies, toxins, neoplasia), or infections due to viral, bacterial or parasite diseases.
Hypothermia is usually an indication of exposure to cold or circulatory shock.