Anagallis arvensis poisoning in cattle and sheep in Uruguay.

Outbreaks of Anagallis arvensis poisoning were observed from 1994 to 1998 in cattle and sheep in Uruguay during December and January. Cattle morbidity varied between 3.2 and 53.2% and lethality 42.6 and 100%. Sheep morbidity was 2.8 to 42.9% and lethality 81.3 to 100%. Nine outbreaks occurred on barley and wheat stubble, and 1 in a field previousy ploughed but not cultivated. Clinical signs were weakness, staggers, diarrhea (sometimes bloody), coma, and death. Serum levels of creatinine and urea were elevated. Gross lesions were characterized by sc petechiae, fluid in body cavities, mesenteric and perirenal edema, yellowish or pale kidneys with petechiae on the cortex, esophageal erosive lesions or ulcers, and hemorrhagic abomasitis and enteritis. Severe nephrosis was observed histologically. The green plant collected in a field where an outbreak occurred was administered to 2 sheep at doses of 160 and 224 g/kg bw and produced clinical signs and pathology similar to those observed in field cases.