The nose myth
Many people touch a dog's nose to decide whether the animal is sick. In a prospective study of 100 emergency patients, thermographic nose temperature showed virtually no correlation with rectal temperature.
A nose may become temporarily dry after sleep, in air-conditioned rooms, or because of normal changes in surface moisture. Warm or dry is not a diagnosis.
What to watch instead
Changes in the whole animal are more informative: lethargy, loss of appetite, shivering, altered breathing, vomiting, diarrhea, pain, reluctance to move, or markedly unusual behavior deserve attention.
Fever requires proper body-temperature measurement and veterinary interpretation. Never give human medication without professional guidance; several common drugs are toxic to pets.
SCIENTIFIC SOURCES