This question does not make any sense. Are you asking what's the meaning of a cow "biting at her rear" or that she's getting ready to give birth and biting at her rear or something else entirely? It almost sounds like a rhetorical question, or a question that answers itself, with you asking what the meaning of a biting her rear is and pretty much answering it by also mentioning that she is getting ready to give birth.
It could mean that a cow is ready to give birth.
your fish could be dying or it could be ready to give birth, or it might just be sick.
Mammary glands in mother cats start producing milk just before birth. It is a good sign delivery is near. There is nothing wrong with mother cat, she is getting ready to feed those little babies.
If your dog hides under a building, it might mean that it is sick or it might mean that something else is going on. The dog might be frightened and be hiding, or, if it's a female, she might be creating a nest and getting ready to have puppies.
Milking a snake is the term used for getting venom out of a living snake. It is done by hooking the snake's fangs over the edge of a glass as if it was biting something and pressing on the venom glands. The venom is then used to create anti-venoms and in medical research.
It means they are getting ready to MATE
ready to party!
No not really, your body is getting ready for the real thing. These early contractions are very light compared to the real thing. If you are worried, time these contractions, if they are not steady, they are just your body getting ready for birth.
It could mean that a cow is ready to give birth.
Getting ready - making preparations
"How are you getting ready?"
it could mean your fertile and getting ready for ovulation.
Its means she is making her nest ready for birth.
when they say wind a baseball they mean getting ready to pitch/throw it
Your body is getting ready to have the baby. Maybe your in labor.
If your mouse is getting fat and is starting to nest that means she is pregnant. and is getting ready for her babies.
It means like lets start the fight (boxing match).