I've witnessed many births both human and animal. I've had four of my own children with three being born at home with no drugs. Those born at home were 10 lbs 8 oz, 10 lbs 2 oz and 10 lbs. I had no anesthesia. Women experience considerable pain and it is evident when witnessed. When an animal has it's babies there seems complete calm, no screaming and they just kind of come out.

It appears that animals do not feel pain or distress during an uncomplicated birth. There are no noises that I have witnessed.