Same as any other dog id say, During the first stage of labor the cervix begins to dilate and uterine contractions begin. These contractions are painful and perplexing to the dog. She will appear quite uncomfortable and restless - pacing, shivering and panting. She probably will not eat and she may even vomit. Some dogs whine persistently. Others occupy themselves building a nest. Uterine contractions, although occurring, are not as easy to see as in humans. This is the longest stage of labor. It generally lasts six to eighteen hours. By the end of this period the dog's cervix will have completely dilated for the puppies to pass. During this period keep the mother's environment quiet and calm. I usually shut them off in a darkened area such as the bathroom
http://www.2ndchance.info/caninelaborstages.htm
http://www.2ndchance.info/caninelaborstages.htm