They produce milk just like any other cow that is pregnant or not.
To make her stop producing milk.
She'll just stop producing milk after a few days.
The daily milk production of the highest milk-producing cow can range from 50 to 100 pounds per day.
lucy
It's possible, but if you catch that milk-thieving cow right away and separate her from the herd to wean her from doing that (or just outright cull her) the open cow shouldn't produce, or rather continue producing milk.
Simple: don't milk her, and don't breed her.
Neither, except if you are referring to how it comes from a cow and is the source where many other dairy products are made, in which case it would be "producing." Logically, A cow produces milk, and it is consumed by the calf or by humans.
The Holstein.
The part of a cow that releases milk is the udder. The udder consists of four teats, each capable of producing milk. Milk is produced in the mammary glands within the udder and is released when the cow is milked.
This will depend if she is at her peak of lactation, when the calf is drinking the most milk, therefore she is producing more. In this case she can be still producing milk for 3 or even 5 months after that. However, if the calf is nearing weaning age (about 10 months), than the cow might be producing milk for about 2 months. This will change from cow to cow depending on how well they produce milk, heavy milkers will produce longer than light milkers.
This is the period where the cow is producing milk, and is always after giving birth to a calf.
Udder enlargement, equal quarters