The animal world is also full of unusual pathologies that defy logic and veterinary medicine. Some are genetic, others are linked to the environment, viruses or even unknown causes. Here are 20 of the rarest diseases documented in animals:
1. Cyclopia.
A genetic anomaly in which the animal is born with only one eye in the center of the forehead. It has been documented in sharks, cats, sheep and other animals.
2. Extreme feline polydactyly.
Some cats are born with 6 or more toes per leg, which is usually not serious, but in extreme cases can cause bone deformities.
3. Papillomavirus in rabbits (oral papillomatosis)
Causes horn-like tumors on the face or mouth, giving rise to the “jackalope” myth.
4. Capture myopathy in deer and antelope.
Extreme stress upon capture causes a massive release of muscle enzymes that can cause paralysis or death.
5. Flying fish syndrome (koi carp)
Some fish develop a swim bladder problem that causes them to float sideways or even leave the water accidentally.
6. Dancing bear syndrome.
In bears rescued from captivity, they present repetitive movements, swaying and compulsive behaviors due to extreme stress.
7. Malignant hyperthermia in pigs.
A genetic mutation causes certain pigs to suffer extreme fever under anesthesia and may die during surgery.
8. Chagas disease in raccoons and opossums.
Transmissible by a parasite, it causes heart failure in wild animals, although many are asymptomatic carriers.
9. Dancing elephant syndrome.
In circus elephants subjected to long chains and cement floors, they develop rhythmic swaying and neurological stereotypies.
10. Herpes virus in sea turtles (fibropapillomatosis).
Produces large, deforming tumors in the eyes, neck and limbs, making feeding or swimming difficult.
11. Extreme leucism in birds and reptiles.
Unlike albinism, leucism erases pigments in parts of the body, leaving animals partially white or with patches.
12. Transmissible Tumors in Dogs (TVT)
A rare case of contagious cancer among animals, transmitted by sexual contact. It is treated as if it were a venereal disease.
13. Wobbler syndrome in horses and large dogs.
Neurological disorder in the cervical spinal cord that causes instability, incoordination and tremors when walking.
14. Mad Cow Disease (BSE)
A neurodegenerative disorder caused by prions, resulting in behavioral disturbances, tremors and death.
15. Progressive retinal degeneration in dogs.
Hereditary disorder leading to progressive blindness, even in well-maintained breeds.
16. Inclusion Body Disease (Inclusion Body Disease)
Viral disease affecting boas and pythons, causing bizarre twisting, lack of coordination and anorexia.
17. Bee Exhaustion Syndrome (Colony Collapse)
A mysterious condition in which worker bees suddenly disappear, leaving empty hives.
18. Stranded dolphin syndrome (mass stranding)
Although not yet fully understood, some groups of dolphins appear stranded en masse on beaches, with no apparent cause.
19. Double head or bicephaly.
Congenital malformation where an animal is born with two heads. It occurs in snakes, turtles and other reptiles.
20. Osteopetrosis in birds.
A rare bone disease that causes an abnormal thickening of the bones, making them more fragile instead of more resistant.
These rare diseases are reminders of the complexity of the animal world and how much remains to be understood in veterinary biology. While some are just natural curiosities, others require urgent attention and protection of the affected wildlife.
