Fancy Rat Variety · Domesticated brown rat (variety, not a separate breed)
Dumbo
Large, low-set ears give the dumbo rat its endearing cartoon-like look.
By the WARN Research & Conservation TeamChecked against IUCN Red List & CITES sourcesLast updated
In brief
The Dumbo rat is a variety with large, round ears set low on the sides of the head rather than on top, giving a distinctive wide-headed look. The ear position is purely cosmetic and does not affect care.
Dumbo: At a Glance
| Origin | Domesticated brown rat (variety, not a separate breed) |
|---|---|
| Size | Small (body 20–25 cm plus tail) |
| Typical weight | Does 250–400 g; bucks 350–550 g |
| Lifespan | 2–3 years (occasionally longer) |
| Coat & markings | Standard coat with large, low-set, rounded ears |
| Temperament | Gentle, sociable, affectionate |
| Best suited to | Older children and adults; must be kept in same-sex groups, never alone |
History & Origins
The Dumbo mutation arose in the United States around 1991 and was standardised by the AFRMA. The low ear set is a recessive trait. Dumbos are often perceived as especially gentle, though temperament depends far more on socialisation than on ear type.
Dumbo Fun Facts
- Dumbo ears are set low on the sides of the head, not on top.
- The mutation appeared in California around 1991.
- Ear type is cosmetic and does not change hearing or care needs.
- Dumbos can have any coat colour or marking.
Dumbo Common Health Issues
Conditions seen more often in this breed, and how owners and vets help manage them. This is general guidance, not veterinary advice — always speak to your vet.
Respiratory disease (mycoplasma)
Most pet rats carry Mycoplasma pulmonis, which can flare into sneezing, laboured breathing and a clicking chest, especially in dusty or ammonia-rich cages.
Care: Use low-dust bedding, keep cages clean and well-ventilated, and see an exotics vet early for antibiotics.
Mammary tumours
Rats commonly develop mammary lumps — usually benign fibroadenomas but sometimes malignant — that can grow large.
Care: An exotics vet can remove tumours surgically; spaying females greatly reduces the risk.
Overgrown incisors
If the continuously growing front teeth misalign, they overgrow and stop the animal eating.
Care: An exotics vet trims overgrown teeth and checks for the underlying cause of the malocclusion.
Help animals in need
World Animal Rescue Network funds partner-led rescue, veterinary care and protection programmes across South Asia, Southeast Asia and South America.
