Limiting Nighttime Calving - Frequently Asked Questions

Calf mortality at calving time is reduced significantly with frequent checking of the herd. This supervision is becoming more important with the increasing number of calves with larger birth weights. Therefore it is important to try to calve during the daytime hours when supervision and assistance is most effective.

Can you change the time of day that cattle calve?
Merely changing the feeding time can change the time of calving. Feeding cows at night is the easiest and most practical method of reducing the number of night calvings.

How does feeding in the evenings reduce the occurrence of nighttime calving?
Rumen motility studies indicate the frequency of rumen contractions is lower a few hours prior to calving. Pressure in the rumen begins to decrease in the last 2 weeks of gestation, with a more rapid decline during calving. It has been shown that night feeding causes pressure in the rumen to rise at night due to feed volume in the rumen from evening feeding and decline during the daytime.

What are the reasons to eliminating nighttime calving?

There are several benefits to eliminating nighttime calving;
Calving difficulties are easier to manage during daylight
Daylight births give calves time to dry off before the sun goes down
Predators are less likely to strike during the day
It is easier to find calving cows in larger areas and in those areas that have blizzards throughout the calving season reducing losses due to snow and freezing temperatures
Feeding in the evening helps maintain body temperature during cold winter nights

How much can feeding in the evening increase daytime calving?
A British study involving 162 cattle from 4 different farms compared the percentages of calves born from 5:00 a.m. to 10:00 p.m. with cows being fed in the morning versus feeding in the evening. 57% of the calves born during the day were from cattle fed at 9:00 am versus 79% born during the day when cows were fed at 10:00 p.m. A study done in Iowa with 1331 cows from 15 farms showed that 85% of the calves were born between 6:00 am and 6:00 p.m. when fed once daily at dusk.

This graph was taken from the Cow-Calf Corner of Oklahoma State University.

What about large cattle operations?
For larger operations it may be physically impossible to feed all the cows after 5:00 p.m. With operations of this size it would be important to feed the first and second calf heifers in the evening, as they are the animals in need of the most attention during calving. The mature cows could then be fed earlier in the day.

How much time should heifers and cows be allowed to be in labor before assistance?
This is another reason behind influencing the time of calving, as research has shown that once in Stage 2 of labor (Stage 2 is defined as the portion of the birthing process from the first appearance of the water bag until the calf is delivered) time is limited. Studies have shown that Stage 2 is short, approximately 60 minutes for first calf heifers, and 30 minutes for mature cows. This is important, as the window is small before assistance may be needed, and it is easy to miss a cow or heifer calving during the dark. By getting more cows and heifers to calve during daylight hours, will allow assistance to be given early and result in fewer deaths and also result in healthier more productive cows.

Calving Season - Cows
Calving

Prepared by Nanita Blomquist, Ag-Info Centre, Alberta Agriculture and Rural Development

For more information about the content of this document, contact Barry Yaremcio.
This document is maintained by Marie Glover.
This information published to the web on March 4, 2004.
Last Reviewed/Revised on February 9, 2016.