1. Nitrate and Prussic Acid Poisoning Floron C. Faries, Jr. DVM, MS Professor and Extension Program Leader for Veterinary Medicine Texas Cooperative Extension Texas A&M University

2. Nitrate in All Forages Under growing conditions of moist soil In plant nitrate converted to protein In plant nitrate does not accumulate In rumen nitrate converted to protein

3. Under no growing conditions of stress Weather, physical damage, heavily grazed In plant nitrate accumulates In rumen high nitrate converted to nitrite In blood high nitrite is poison Nitrite poisoning Blood cannot carry oxygen Death by asphyxiation

4. Fresh or dry forage Johnson Grass Sudan Sorghum Sudan-Sorghum Wheat Oats Rye Ryegrass Bermuda Fescue

5. Weather Growth cease/nitrate accumulates Cold Hot Cloudy Shade

6. Physical damage Growth cease/nitrate accumulates Heavily grazed Nitrate in lower stems and roots

7. >1% nitrate of ration (>100 PPM) Energy feeds > Conversion

8. Prussic Acid in Stressed Forages Under growing conditions of moist soil In plant prussic acid does not accumulate

9. Under no growing conditions of stress Drought, hot, frost, freeze In plant prussic acid develops In rumen high prussic acid converted to cyanide In blood high cyanide is poison Cyanide poisoning Blood cannot carry oxygen Death by asphyxiation

10. Fresh forage Johnson Grass Sudan Sorghum Sudan-Sorghum

11. Weather/Damage Frost wilt winter Hot dry summer 3 days New growth 10 days Hay fill