Producers who supervise first-calf heifers throughout the night know they need to protect their bottom line. It definitely helps to supervise, but some experts suggest you do not have to stay up all night. Studies have shown that feeding cows at night reduces overnight calving.
The fact is, good calving management is critical to calving success. Such management includes supervision and intervention in order to prevent calf losses. This is especially true during active labor. Studies repeatedly show that active labor should be limited to two hours if the fetus is in a normal position. Further, assisting cows at 80 minutes after the water bag is visible drastically decreases the risk of stillbirth.
Animal experts agree that for reasons they aren’t completely sure of, feeding cows at night does reduce the incidence of overnight calving. It is difficult to pinpoint exactly why this happens but the consensus is that it has something to do with the impact of hormones.
Studies on the way rumen moves show a decrease in rumen contractions in the hours before birthing occurs. To put it simply, when cows are fed at night during the approximately 14 days before calving, pressures within the rumen are more likely to rise at night and then decline during the day. These studies are confirmed by studies in the United States and Canada.
The results of these studies seem to indicate that if producers could feed forage in the early evening and increase the rate of calving during the day. Research shows that when cows had continual access to round hay bales but were fed supplements around dinner time, 70 percent of those cows would deliver during the day, or between the hours of 6 a.m. and 6 p.m.
The study further concluded that if an operation offered feeding at all times, round hay bales and ring feeders be housed inside a fenced enclosure. This would allow producers to give cows access to hay in the evening and at dusk. The cows could then be moved to an adjoining pasture in the morning. This method of feeding is believed to result in a greater number of calves born during the day.