Excluding that which comes from momma humans, most of the milk consumed by humans comes from cows. I get that there are some cultures that drink the milk of other mammals such as goats, but are there any that are strictly verboten due to the limits of the human digestive system? Could I down a cup of chimp milk and live to tell the tale? Dolphin milk? Rat milk?
There are no mammalian milks that would be poisonous or harmful to humans. Many would taste horrid. The milk of sea lions, e.g., is 40% fat and has no lactose.
Getting enough to drink would be another issue. Pigs are notoriously hard to milk, which is why cultures that use pigs as the dominant source of meat, such as the Chinese, tend not to use any milk in their cuisine. It takes dedicated scientists to express sufficient milk out of any number of mammals to do studies on it.
I have it on the best authority that you should never drink Tiger milk straight from the teat.
I understand that in addition to goats, some cultures commonly drink milk from camels or yaks.
I’ve also heard since I was a child that yak’s milk is pink. Why is this?
Bat milk?
This is a mild hijack, but it turns out, based on the way giraffe milk curdles, that giraffe is kosher. Mazel tov!
Not sure who posted this or whether this was suppose to be ironic or not, but considering that people evolved to digest lactose (three separate times) means that milk must have been an important food for those cultures for thousands of years, and that there was an evolutionary benefit for drinking milk.
Never try to milk a bull.
horse, water buffalo, deer and moose are also milked in some cultures.
Am I the only one envisioning a tiny scale model cowshed for the rats? 
Oh, and did you hear about the Dolphin dairy farmer? Yeah, he drowned. :eek:
What, like this?
I read that " …deer and mouse" and almost choked. Thanks! The images in my head will now keep me amused.
I think the yak gets it’s name from people that tried to drink the milk.
How could there be non-mammalian milk? By definition, a creature that produces milk is a mammal, right?
Okay, now that I got that out of the way…
Do carnivores produce less milk than herbivores?
I wanted to post that all reptile milk was safe and low calorie, but didn’t until now.
I know of no animal with poisonous milk. There is milk that is super high in fat so not good for a human to consume in large amounts.
Yeah, but I am not going to volunteer to milk the platypusses. Venomous mammals, God knows what the mild is like.
Pigeons and doves produce a nutritious secretion in their crops, commonly known as “pigeon milk,” on which they feed their chicks. Similar substances are produced by the Greater Flamingo and the Emperor Penguins.
Moosemilk is not actually produced by milking moose.
On the off chance that this wasn’t intended as a woosh, what cultures milk moose as a general thing?
Moose Milk, not to be confused with the alcoholic drink Moosemilk actually is common in Russia, according to wikipedia as well!