From Sally Parsons
Human mucus secretions are indeed often green
(Last Word, 25 April).
However, it is a little known fact (including, apparently, the authors of
many books on pet care) that the mucus secretions of domestic rats are red in
colour, even when they are healthy. I can vouch for this, having rushed my pet
rat to the vet with an apparent nose bleed.
Eastbourne, East Sussex
