Upper respiratory infections are rare in healthy ferrets that
are kept in a good environment and have limited to no contact
with sickly animals. Ferrets that are most susceptible to
infections include kits, older ferrets, ferrets with weakened or
suppressed immune systems, and ferrets living in unhealthy
conditions (dirty cage, too warm or too cold, etc.). The signs
of an upper respiratory infection include: Nasal discharge -
clear, yellow, or green The color of the nasal discharge will
probably give your veterinarian an idea of how severe the
infection is, and whether or not it can be treated with
antibiotics. The decreased appetite is due to the congestion.
Ferrets with upper respiratory infections cannot smell their
food, and it's hard for them to swallow with blocked nostrils,
so they eat less. A respiratory infection can occur when a
ferret is exposed to another person or animal with an infection.
It can also develop when an animal lives in a dirty environment
that is full of bacteria. Additionally, a re