When nitrate levels get too high in feed it can result in rapid death and abortions from lack of oxygen.
Nitrate poisoning is extremely dangerous, often the first sign seen is sudden death (multiple dead/ down cattle). This makes it vital to manage the risk.
New grass paddocks and crops should be tested during high-risk periods, first grazing periods often pose the highest risk. On farm nitrate kits are available from the clinic. These are a quick, easy and cheap way to test your pastures prior to putting stock on. This is the best way of controlling nitrate risk.
Feed cattle first to prevent stock from gorging themselves on pastures and crops. Check your animals a couple of hours after putting them on a new break. In higher-risk situations, only graze the paddock for 1-2 hours or defer it to a lower risk period.
Symptoms of poisoning include staggering, fast breathing, muscle tremors, drooling and brown mucous membranes (vulva, gums and white of the eyes). Call your vet at the first sign of trouble, don’t wait until sudden death is a symptom. Remove all animals from the affected pasture. Treatment is usually very quick and effective, however abortions following poisoning are common.
Dr Lara Lambert BVSc - Mixed Vet at our Taupiri clinic