Is that... controversial? Obviously a cow normally gives milk without being pregnant. It wouldn't be able to feed its calf otherwise.
Cows simply produce milk like chickens lay eggs.
Consider how imagery of a farmer inseminating a cow with his arm disappearing up some tract or fitting a spike to the baby so it can't drink its mom's milk -- or farm conditions in general -- are basically shock footage that people are insulated from until they maybe chance upon a movie like Dominion.
These are not sapient beings that are capable of looking out for their own well-being. We've bred that out of them over hundreds of human generations.
The gestation period of a cow is approximately 9 months, similar to humans, by coincidence. Only a cow that has given birth to a calf will produce milk. The normal lactation period is 305 days before the cow is "dried up" before giving birth again. 10,000 pounds of milk is considered a good lactation total. Typically, cows are bred to calve once per year. Typically going through 10 lactations before that one way trip to MacDonald's.
Dairy bulls are notoriously nasty creatures, so artificial insemination is almost universal in the dairy industry. The "tract" that you speak of is the cow's colon. The technician is careful to guide the pipette so as not to injure the animal, and the colon provides convenient access to feel what is going on inside.
If you are squeamish about such things as cow's colons, then vet school is not for you.
e.g. "[They might assume] cows simply produce milk like chickens lay eggs."
It's normal to never really think about it -- our society is set up so that you never have to. The secretion comes in a jug, the meat comes in cellophane, and that's it.
I think a lot of people don't realize we're hijacking their reproductive systems, instead assuming cows constantly produce milk.
One could argue there's more suffering in a glass of milk than a steak, which makes ethical vegetarianism flawed despite its good intentions.
What I find quite bizarre that in India (where I am from) milk is considered ethically vegetarian whereas unfertilized chicken eggs are not.
But the weirdest experience I have ever had was at the main Google cafeteria. One gentleman with a steak on his fresh plate was quizzing the attendant at length to be sure that the mashed potato was vegan. After many months of thinking I found a plausible reason.
Carnivorous potatoes aren't as tasty?
But there's so much to the linguistics of animal husbandry and dairy that many folks don't know. It goes way deeper than just the milk-oriented terms in the article: Heifer versus cow, freshening and calving, steer versus ox versus bull, AI (not the LLM kind) versus natural service, the barn, parlor, and pasture, and more. Plus plenty of technical knowledge. If you're not hand milking, how many mmHg of negative pressure should you use? Do you use a surcingle, or a claw, or a robot?
Even in the milk-oriented terms, there are others not covered by the article. HTST and UHT aren't the only options, there's also LTLT. Pasteurization can be done in a pipeline, or in a vat. Smaller vats for home and small farm usage can be multi-purpose: I pasteurized milk and cultured yogurt in mine. Some folks even care about the specific proteins (A1 beta-casein versus A2), which is genetically determined by the cow (and can be bred for).
I got a cow in 2020 and there was a lot to learn.
Not just that. A cow couldn't be a cow if she hadn't become pregnant.
Am I misinterpreting you here? You're saying most people think cows are bred (you know, what causes pregnancy), and presumably think that that calves are born — I've never met anyone who didn't know what a calf is, but somehow don't realize that pregnancy happens inbetween?
But that's not how it works. Every single milk-producing cow must have been pregnant at least once, and typically several times in its life to keep producing desired amounts of milk. And the calves are an unwanted byproduct that must be taken away. At least they're not shredded in a big blender like the male chicks of egg-laying chicken breeds are.
