Cows will produce milk for as long as a producer (dairy or beef) needs to have them produce milk, whether it's a time frame of around 6 to 10 months or longer, depending on their type and class of the cows and the producer's management criteria. The time frame, on average, is between or either 6 to 10 months.
Dairy cows tend to be milked longer than beef cows due to the fact that they're selected to produce milk, not raise a calf. Beef cows will produce milk as long as they have a calf on them.
prolactin
Prolactin
No because all cows, regardless of type, are capable of giving milk, so long as they have already given birth to a calf (very recently) and are lactating. There are people out there that use their beef cows (yes, BEEF cows) to get their milk from that they use for their own consumption. Milk isn't exclusive to dairy cows only, you know.
0 to 2 days
giving birth
Immediately
Just about any condition that isn't too cold or too hot and doesn't experience inclement weather. As long as cows get proper feed which meet the cows' nutritional requirements, they will produce milk and do well enough to produce that milk for you.
Never. Chimpanzees can not give birth to young cows (a calf).
After 3 months
...Seriously?
6 weeks
yes dogs do lose their hair after giving birth and it would last proably for six months.
A cow shouldn't be bleeding after giving birth. She may have a torn uterus, so you'd better get the vet out ASAP.
It should only be a matter of a couple hours.