High Nitrate In Hay Killing Beef Cows In Complex Ways
Part 2 Of A 2 Part Series
COLUMBIA, MO.
Nutritionist Eric Bailey spoke up with a fix. Adding starch to the cow's diet absorbs much of that extra nitrate in the rumen. Normally, farmers are advised to go slow adding corn to a rumen on a hay diet. At first, starch upsets rumen microbes.
In this unusual year, plain corn gives an answer. But adding a protein-rich supplement worsens the problem. Protein adds unneeded nitrogen. At first sign of trouble, take away any protein supplement.
Corn, a starch, speeds up digestion in the rumen. That moves toxic hay right on down the digestive tract.
At first sign of nitrate poisoning, which often can be death, remove bad hay.
As a first step, farmers should test suspect hay for nitrates, says Craig Roberts, MU Extension forage specialist.
“Know your hay,” Roberts said. Know where it came from and whether fertilizer or poultry manure was used. Risks rise in hay made in drought. Hay detective work doesn’t come easy.
Farmers face a serious problem now. After two years of drought, not much hay was baled. Buying good hay becomes almost impossible. It’s hard to find.
County MU Extension centers may have quick-test kits left over from last summer’s droughts. A few drops of the acid turn dark blue on split stems of high-nitrate grass.
Blue indicates a quantitative test is needed.
Evans says quantitative nitrate tests report parts per million. Less than 2,500 ppm seems safe. More than 5,000 ppm means danger. At 10,000, watch out!
Regional MU agronomists and livestock specialists gear up to help farmers sort complex issues.
Evans says added problems come when cold fronts descend from the Arctic. Cattle sense weather changes in advance, and then they overeat, filling the rumen with forage for the cold spell. Even borderline toxic hay not causing trouble becomes potentially toxic in an overloaded rumen.
Pregnant cows near calving are vulnerable. Unborn calves die of nitrate poison. They lack oxygen.
Cows in poor condition suffer most. With low hay supplies and bad weather, cows started winter in lower body condition. Thin cows with less fat reserves are more vulnerable.
Roberts says toxin management includes watching each cow. Some may show early signs of poisoning by their weakness. That warns of complex problems ahead.
Ask for help from veterinarians or extension specialists early rather than later. ∆