Provide clean, visible pasture For ideal calving environment during the summer. Observe Calving Maintain easy accessibility to the maternity area and observe cows close to calving often. One explanation is that many unassisted births are unobserved. Obviously someone observing an easy pull is there to take care of an emergency whether the calf needs assistance or not. If the cervix has not had sufficient time to dilate, forcing the calf can seriously injure the cow and cause undo stress to the calf.
Heifers spend more time in labor and more time giving birth than mature cows.
Labor commences with the onset of uterine contractions and dilation of the cervix. Contractions initially occur approximately every 15 minutes. As labor continues, contractions become stronger and more frequent and the cervix expands to the point that the uterus and vagina form a continuous canal. See Table 2 for average labor and delivery times for a normal birth. Mature cows may need as long as 4 hours and heifers 6 hours to deliver a calf once labor commences.