COLUMBIA, MO. . A yeast culture that has been termed a "lifesaving" feed ingredient will counteract the effects of high-nitrate poisoning suffered by livestock that have consumed high levels of nitrates.According to University of Missouri researcher Stan Grebing, the yeast culture will save the lives of animals that consume high-nitrate water and feeds such as drought stricken, high nitrate silage.

"The poisonous silage has been a problem in the midwest during the last two years because of dry weather", said Grebing," and we're concerned that we'll see more of the same in the future."

He said that bacteria in the rumen convert the nitrate in the silage to nitrite, which is absorbed through the rumen walls into the bloodstream. There it combineswith hemoglobin, prohibiting the animal from carrying oxygen in its blood. The result is that the animal suffocates and dies.In test with lambs, Grebing "orally drenched" them with nitrate. He dissolved sodium and potassium nitrate in water and force-fed the solution. "This was a much higher dose than what the average farmer would see, he added, but he really wanted to test the yeast culture.

He ran two trials on anirnals force-fed high nitrate feeds. The yeast culture proved effective in both testsThere were 20 lambs on the first trial; 16 on the second. Half were fed the yeast culture, half were not. Six of the 10 untreated lambs died in the first trial; six died in the second. Only one treated lamb died in each trial.

"That's a highly significant difference -- enough for us to encourage yeast culture treatments for animals fed high-nitrate feeds and water," said Grebing.

Recommendations call for feeding 500 mg to 1 gram per head per day to lambs and1 gram daily to cattle. Grebing said he was not sure why the yeast culture works, but he expects that it changes bacterial metabolism in the rumen which breaks down nitrates