Time of Feeding Influences Time of Calving and Body Temperature

By Marty New, Oklahoma Cooperative Extension Service SW Area Livestock Specialist

As cowherd expansion continues and first calf heifers are being placed in the herd, we need to consider how to reduce calf mortality. Supervision of first calf heifers and cows that are in need of assistance is an obvious proven method to increase calf survival.

The best and easiest time to observe the herd is within daylight hours. During this time skilled personnel are more readily available to render assistance and neonatal care to maximize the calf crop. Additionally, baby calves born in the warmer part of the day reduce cold stress and have a better chance for early colostrum consumption and ultimately survival.

The easiest and most practical method of inhibiting nighttime calving is by feeding cows at night. The physiological mechanism is unknown, but some hormonal effect may be involved. Rumen motility studies indicate the frequency of rumen contractions decreases a few hours before parturition. Intraruminal pressure begins to fall in the last two weeks of gestation, with a more rapid decline during calving. It has been suggested that night feeding causes intraruminal pressures to rise at night and decline in the daytime.

Pick up the January issue of OKFR to learn more.