Nitrate poisoning in livestock
Nitrate poisoning of livestock is a condition which will affect the ruminant animals from digesting forages or adsorption of water that has high levels of nitrates in them. Under normal circumstances, nitrates are ingested by the livestock and then are converted into nitrites that are then converted to ammonia in the rumen and then into bacterial proteins to can be adsorbed by the body.
Nitrates become a problem when the animal consumes forages that are high in nitrates and the process converts the nitrates into nitrites faster than the process that converts nitrites into ammonia, and this leads to a build up of nitrites in the animals system. When this happens, the nitrites are absorbed into the blood stream and it starves the animals system of oxygen by converting the hemoglobin into methemoglobin that cannot carry oxygen to the rest of the body. The animal then dies due to lack of oxygen in the body.
The reason that this year is of concern is the fact of the uneven rain and nitrogen getting trapped in the forages. When the forages are cut and fed, it leads to higher nitrates being trapped in the plant tissues. It takes three factors to correctly change the nitrate to protein in plants. It takes adequate water, energy from sunlight and a temperature high enough to provide rapid chemical reactions. If one of these factors are limited or changed, the plant continues to absorb nitrogen from the soil and stores it in the stalks and leaves to be converted later.
Many symptoms of nitrate poisoning are: a poor appetite, weak offspring (calves, lambs or kids), abortions, poor growth or general unthriftiness. Factors that can affect this is the age of the animal, body condition, species of the animal, nutrients in the feed or forage, and any other sources of nitrogen coming from minerals or water. All these must be considered when determining if the animal if being affected by nitrate poisoning.
If you have any questions concerning the levels of nitrates in your forages or water and it possibly causing an issue of nitrate poisoning, take a water sample to get tested and/or take a half pound of the forage that you’re feeding to get tested to see what the levels of nitrogen are. Then use the following chart to determine the level to see if it affecting the animals performance.
NO3 intake in Grams per 100 pounds of body weight
< 4.4 – normal or considered usual intake generally safe in all conditions.
4.4 to 8.8 – safe for most animals. May be hazardous to pregnant or very young animals.
8.8 to 13.2 – potentially dangerous to pregnant or young animals. May result in poor appetite, slow growth, abortions, and decreased milk production.
13.2 to 25.6 – hazardous intakes for all levels of livestock.
Over 25.6 – toxicity likely to most animals.
You may get your results back in different forms and to help you convert them to match the chart above use the following conversions:
Converting (NO3-N) to (NO3) — multiply by 4.4
Converting (NO3) to (NO3-N) — multiply by 0.23
Everything in life takes a certain level of balance to have the animal perform at peak growth and production and by knowing what you’re putting in the animal you can determine you end result. Good Luck and take precaution this year.
** Technical information provided by research done by the University of Wisconsin Extension and from publications from J.W. Crowley. 1985. Effects of Nitrate on Livestock. American Society of Agricultural Engineers. Paper Number 80–20026.
Matt Aultman is the chairman of the Agriculture Committee or the Darke County Chamber of Commerce, and serves on the membership committee of the Darke County Farm Bureau.