Encouraging daytime calving
By Robin Reid
River Valley District Extension Agent
At our recent Winter Ranch Management Seminar at Cloud County Community College, we had a great group of producers and students for the new “town hall” format. Questions were asked of our K-State Research and Extension animal science specialists on a variety of topics dealing with cattle production. I wanted to briefly talk about one of the questions that came up during that meeting; how do you get cows to calve during the day?
The most effective method of encouraging daytime calving is to feed cows in the evening. It is not known for certain why this works, but researchers have some theories. Contractions in the rumen fall within a few hours of calving along with intrarumenal pressure, which falls in the last two weeks of gestation but declines rapidly at calving. By feeding cattle in the evening, rumen contractions and intrarumenal pressure both rise and therefore cows tend to calve more during the day.
Several studies have quantified this in a production setting. In Canada, 104 Hereford cows were fed twice a day; Group 1 being fed at 8 a.m. and 3 p.m., and Group 2 fed at 11 a.m. and 9 p.m. Thirty-eight percent of the cows in Group 1 calved during the day, while almost 80 percent of cows in Group 2 calved during the day. A British study found similar results when feeding 162 cows once a day. The control group was fed at 9 a.m. and had 57 percent of cows calve during the day. In contrast, the late fed group was fed at 10 p.m. and experienced 79 percent of cows calving during the day. The most convincing study was conducted on 1331 cows on 15 farms in Iowa. Cows were fed once a day at dusk and 85 percent of cows calved between 6 a.m. and 6 p.m. This study also found that this effect was the same whether cows were started on night feeding one week prior to calving or two to three weeks prior to calving.
All of this research sounds convincing, but may not be practical in every production setting. If cows are fed an unrestricted feed source (such as round bales), the timing of feeding supplement can also effect daytime calving. A study completed at Oklahoma State found that if supplement is fed in the morning, 50 percent of cows calved during the day. Of the cows that were supplemented in the early evening, 72 percent calved between 6 a.m. and 6 p.m.
If cows are only fed hay, restricting access to the hay can also encourage daytime calving. For example, by putting bale rings in a small paddock that can be closed off from the other pasture and only allowing cows to eat hay at night has been found successful in inhibiting nighttime calving. Keep in mind with this method that it is very important to make sure your cows are still receiving adequate nutrition and not losing body condition at this critical period.
Whichever method works best for your operation can create many advantages if more cows calve during the day. Obviously the amount of supervision at calving can directly affect calf mortality, especially in first-time heifers. By the time a cow or heifer is found in the morning after a long night of calving difficulties, it may be too late to save the calf you worked all year to produce. Or worse yet, the heifer you spent two years developing. Another consideration however, is cold stress on calves. It is typically warmer during the day and calves have a better chance of getting up and nursing earlier. Receiving adequate colostrum will have many health benefits but also better lifetime performance.
Late afternoon or evening feeding may not be practical for every operation but is a management practice to consider. Even if you have already started calving or soon will, you can switch to this method and still see this benefit. With calf prices predicted to be high next fall, one more calf to wean can increase revenue by $1,000, so changing to nighttime feeding can pay off quite quickly if calf mortality is decreased.
This is just one of the great topics that were covered at our last Extension meeting. There are still more K-State Research and Extension workshops to come this spring, so visit our website at www.rivervalley.ksu.edu for more information.