A cow is born with nipples--or rather, teats--therefore this question is impossible to answer. However, if you are asking about the formation of an udder being an indicator to when a cow will give birth, it could be anywhere from days to several weeks.
Beef cows nurse their young for 6 to 8 months on average before being "force" weaned. Some producers let their cows nurse their calves for 10 to 11 months before they kick them off--i.e., natural weaning.
Cows can give birth any time of the year, so long as it's been around 9.5 to almost 10 months after conception. Those goes for heifers as well.
--milk them
About 12 hours..if your a man
a long time
For the vagina about a week nipples until she done nursing, after nursing it will take 10 to 14 days till all milk is dried up
An average of 42 days is the time is takes for a ferret to give birth.
It takes 12 months for a dolphin to give birth to another dolphin (calf).
It takes about 60 to 63 days for a female coyote to give birth.
5345636
as long as you don't try to pierce the nipples
I think six weeks
just over a year
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