Nitrate intoxication due to ingestion of pigweed red-root (Amaranthus retroflexus) in cattle

Nitrate toxicosis associated with consumption of pigweed red-root (Amaranthus retroflexus) was diagnosed in a small herd of cattle in the suburb of Mashhad, northeastern Iran. The clinical signs were ruminal tympany, incoordination, tachycardia, dyspnea, head pressing, aggressive movements and jugular distension. Seven animals including 3 young calves and 4 cows died of intoxication; other affected cattle were treated by intravenous administration of epinephrine and ascorbic acid. No further mortality was observed after the treatment. One of the treated cows aborted a 6-month-old fetus more than three days after intoxication. Two samples of suspected plants were analysed for nitrate. The nitrate content of those plants was 6.6% and 10.4% in dry matter.