If corn ear drop exceeds 8 to 10 bushels per acre this fall, develop a strategy to mitigate potential grain overload in cows when you turn them out to graze harvested fields, advises says Karl Hoppe, area livestock systems specialist at the Carrington Research Extension Center.

Too much corn will cause acidosis, lameness, abortion and, in extreme cases, death.

To determine the amount of corn remaining in fields planted in 30-inch rows, count the number of 8-inch ears (or equivalent) on the ground along 100 feet between two rows, and then divide the total by 2. Do this for at least three 100-foot-long strips in the field to get a good estimate of corn remaining in the field. The result is the pounds of grain per acre on the ground. Each 8-inch ear of corn contains roughly a half pound of grain.

Fara Brummer, North Dakota State University area livestock systems specialist at the Central Grasslands Research Extension Center, suggests the following steps to reduce the risk of cattle getting sick from eating too much corn:

1. Carefully consider the class of cattle allowed to graze cornstalks. Cattle new to eating corn (calves or yearlings) will take some time before they actively seek corn. This delayed consumption can serve as a good acclimation period. Cows with experience grazing corn aftermath will look for grain and downed ears immediately when turned out. Consider grazing calves, yearlings or cull cows on fields to clean up some of the corn before turning out pregnant cows.

2. Provide some type of ionophore-containing supplement.

3. Adapt cattle to corn before turning out to graze cornstalks. Start with 3 pounds daily and move up to 7 or 8 pounds during a 10-day period before turnout.

4. Cross-fence fields to minimize the amount of the field that cows have access to at any one time. Early in the grazing period, this may mean moving the fence daily.

5. Do not turn hungry cattle out to graze. Provide good-quality hay so cattle don’t overeat corn immediately. Also, set out bales of good-quality hay in cornfields so cattle have access to hay while grazing corn.

6. After cattle are past the initial risks posed by grain remaining in the fields, producers have several other management considerations. One of them is supplementation. Depending on the desired level of performance, producers should provide supplemental phosphorus, vitamin A and trace minerals once the grain and better-quality forage material have been consumed.

7. Closely monitor the amount of residue remaining on fields and provide supplemental forage or remove cows as necessary. Do not force cattle to eat stalks and cobs because they are low-quality feed.

See the NDSU publication, “Utilizing Corn Residue in Beef Cattle Diets.”

Source: NDSU Extension