Drought-stressed forages bring feeding challenges, including increased risk of nitrate toxicity.

When unconditioned cattle consume plants containing high levels of nitrates, the nitrate-to-nitrite conversion exceeds the ability of the rumen microbes to convert nitrites to ammonia, says Dick Wallace, University of Illinois extension dairy veterinarian. This reduces the oxygen-carrying capacity of the animal’s blood, and can lead to death in severe cases.

Therefore, consider testing drought-stressed forages for nitrate levels. Veterinary diagnostic labs or forage-testing labs can analyze this for you.