I have seen pictures of white tigers whose inbreeding (for the color) made them look like they have the equivalent of Down’s Syndrome in a human. I’m not sure if it’s just a physical mutation or mental as well but googling down’s syndrome tiger pulls up lots of links I can’t check right now.
Edit to add: my dog took a whole year to be trained on how to get food out of his Kong without pushing it into a corner and then staring at me helplessly. I had to teach him to paw at it to pull it back. One year. He also knows no commands except “Come’ere” and “off the bed!” but that could be my fault.
Just for accuracy’s sake - Down’s Syndrome is caused by an extra copy of an entire chromosome, rather a lot of genes. To be specific, chromosome 21. Most other instances of getting an extra chromosome results in a non-viable fetus.
I believe there is a similar, though not identical, syndrome in the Great Apes due to an extra chromosome. Chromosome trisomy might well occur in other species but whether the result would survive to birth, or after birth, and what the exact effects would be I have no idea.
I’ve had one cat that I would describe as mentally retarded. His behaviors were very strange, he was very slow and not at all bright. We had 2 of his sisters as well, they were both of apparently normal intellect.
A couple litters ago I got a baby rat who had some very strange physical characteristics, coupled with apparently mental retardation. She had very wide, deep-set little eyes, a flattish face, muscle flaccidity and a very round belly, and was very much smaller than any of her litter-mates. She was slow, uncoordinated, and didn’t seem to understand much about the world, unlike most rats who are frighteningly smart. I’ve been breeding her bloodline for years and have never seen anything like her - 2 of her sisters and 1 of her brothers have been bred and all the offspring have been normal. I assume it was just a birth defect that led her to be as she was. She had an extremely outgoing, sweet and cuddly temperament and made a fantastic pet, but you couldn’t let her wander off because she’d fall off of things or get lost and not come back.
I’ll raider you with my nine month old 98lb Great Dane. I love this dog, but he pees on his front paw every single time. Firefly he will learn to lift his leg eventually as I am getting tired of giving him paw baths two or three times a day.
I presently have a goat who is profoundly stupid, highly unusual in this clever and curious species. For example, it has taken her about four months to figure out that every morning she goes into the milking room to be fed and milked (which lactating animals enjoy). That is, she was continually surprised and alarmed to be patiently escorted away from the other goats, to be put on a stand, and have grain put in front of her. A typical goat learns 7 a.m. --> go jump on milk stand and eat! in about three reps.
She does other hopelessly dimwitted things as well. I’ve had very stubborn goats but never a moron goat before.
I once adopted a stray kitten that had been starving and while she was a wonderful pet - beautiful, loving - she was very dumb. took her months to learn her name and she was only so-so in the litterbox.
she would *frequently *dig a hole, stand in it, poop on the hill behind her and then run off startled when the poop would roll down the hill and hit her leg.
