How long does it take for a cow or heifer to give birth?

Answer 1

It depends on the age of that cow or heifer, what position the calf is in when it enters the birth canal, and what size the calf is. Some may even say that it also depends on the sex of the calf as well. It should only take a few hours or more for the calf to start to emerge during the early stages of labour, being presentation of the water sac and the calf's front hooves. Once the water sac emerges, it usually takes from a half hour to an hour for the calf to be expelled. Most cows that have had experience will only take 10 to 30 minutes to "spit" the calf out. Cows that have been bred to a bull that does not have the genetics for easy calving tend take longer due to the fact that they have a bigger calf to push out. Heifers, on the other hand, may take several hours to give birth because of their smaller pelvic opening. Heifers that have not been bred to a calving-ease bull tend to end up with more problems, and will take longer to calve out. If a calf is not in the proper position it will also take longer, and may end up needing help from a vet or the rancher/farmer to pull the calf out and ensure the cow/heifer and calf's survival.

As far as the sex of the calf is concerned, there are some claims that if a cow retains a calf for longer or takes longer to give birth the calf's a bull calf; the opposite is true if it's a heifer. Not sure if this has any scientific merit, or if it's just some old wive's tales.