Yes, always.
A cow that is close to calving, and is far along in her gestation period.
A cow that is very close to calving or which calving is imminent.
Calving.
The udder will only swell, the cow is dropping her milk into the milk cisterns in the udder for the calf to suckle.
A breaching cow could mean a cow that is calving out a backwards calf.
Don't wait. This is a good time to put on the calving chains and start pulling. Make sure the cow is secured in a head gate first, though, before you latch on the calving chains on the calf.
The anestrous period for a cow or heifer after calving is 45 to 60 days, but can range between 25 to 80+ days.
The average should be around 45 to 60 days at the least.
Parturition or calving, just like with any other cow.
the cow will get restless and will isolate itself from other cows.
A calving pen, or out on the pasture.