Are nosebleeds unique to humans?
Cats, dogs and other animals can suffer from epistaxis.  The causes differ depending on the animal.


  foreign things in the nose, abscess, cancerous growth, snake bite, some poisonings and diseases especially in the trachea and lungs and anthrax. Sometimes excessive sneezing or coughing can result in nose bleeding as well. All animals are susceptible to get nose bleeding.


They would need to see their vet or owner to get it treated.

https://www.thevillager.com.na/articles/7474/Dealing-With-an-Animal-Bleeding-From-the-Nose/