Question: signs a cow will calve?
Answer: Rapidly growing udder. Now, this can be a bit deceiving, since a cow will start “bagging up” sometimes months before their calving date. ... 
Springing in the Back End… Also know as a puffy, relaxed vulva. ... 
Disappearing pelvic ligaments. ... 
Mucous & discharge. ... 
Restlessness and weird behavior.