By KEVIN WALKER Michigan Correspondent
LANSING, Mich. — A recent case of rumen acidosis, or grain overload, in a farmer’s cattle serves as a reminder this problem can have tragic consequences. Parker, a farmer in the greater Lansing area who asked that his last name not be used, recently suffered about $10,000 worth of losses when several animals from his herd died after suffering from grain overload. “We ended up losing a total of six cattle,” Parker said. “It’s kind of a blow to us, but it’s the nature of the business.” Cattle ranchers such as Parker routinely turn cattle out on corn stover as a way to use the entire plant. Corn stover can be an excellent feed source for cattle; however, it can be a problem if there is much corn grain still present in the field. That’s what happened to Parker. He had a third party harvest a 20-acre field of corn late in the year. Parker scouted the field for grain that might have fallen out of a hopper or transport truck carrying grain, but wasn’t thinking that some plants just might not have been harvested. Unfortunately, there were 2-3 acres of corn that hadn’t been harvested and he didn’t notice them. These are what the cattle were turned out on, and ingesting it caused some to die. Today, cattle are an investment worth $1,500-$2,000 each, said Dr. Dan Grooms, a large animal veterinarian and professor in the department of large animal clinical sciences at Michigan State University. “Cattle are usually introduced to the corn slowly over time,” he explained. “Their rumen adapt slowly to that changing diet. In this case the cattle were used to a grass diet and suddenly they were exposed to a large amount of grain in a matter of hours or minutes. That was the problem.” When cattle are turned out into a field to consume corn stover, the grain is usually completely harvested. Grain is like candy to cattle, Grooms likened. Originally, three cows were found dead in Parker’s field. They had evidence of severe rumen acidosis, including reddening and erosions of the rumen mucosa. The rumen pH was less than 5.0; the normal range is 6-6.5. The rumen’s contents included an abundance of whole kernel and partially digested corn. The diagnosis was acute rumen acidosis, also known as grain overload. Three of Parker’s cows died initially, with three more dying during the next 48 hours. Although Parker didn’t mention it in the interview, a statement from MSU suggests the problem may have stemmed from too many cornstalks having been knocked down during harvest. Parker stated there might have been some improper techniques on the part of the harvester, but he mainly blames himself for the problem. Corn can also be knocked down due to excessive wind or excessive ear drop because of late harvest. In this case, the corn was harvested in mid-December. Such a late harvest isn’t all that unusual, Parker stated. “This was one of the last fields that was planted last spring,” he said. “It was a wet fall here and it was pretty cool. It was a late harvest, but not too out of the ordinary for around here. Sometimes people will harvest in the middle of winter.” Grooms noted there are other reasons corn might end up exposed to cattle unintentionally, such as when a hopper or transport truck is overfilled and grain falls out. In addition, an auger sometimes is misaligned and shoots out grain onto the ground. Farmers can avoid grain overload by scouting their fields carefully before turning cattle out onto stover. If excessive corn is present in a field, it’s essential that cattle be exposed to the grain slowly in order to allow their rumens to adjust. Strip grazing is one method farmers can use to reduce exposure to corn grain and force cattle to eat the whole corn cob, husk and stocks, not just the grain. This increases the animal’s fiber intake and reduces grain intake. Grooms suggests providing supplemental hay to increase fiber intake, as well, and to make sure there is plenty of water for cattle. |
