Acute urea toxicity in sheep.

Twenty-seven sheep were assigned to three groups in order to study acute urea toxicity. Groups I, II and III were dosed with 0.5, 0.6 annd 0.75 g/kg of urea, respectively. The mean survival times were 165, 109 and 60 minutes, respectively. The following clinical signs such as pronounced muscle fasciculation, trembling, grinding teeth, ataxia, lateral recumbency, bloating, regurgitation, hyperesthesia, mydriasis and convulsions were observed. Anuria and lack of salivation were also present. The primary cause of death in this study was due to respiratory arrest and not cardiovascular collapse. Plasma examinations showed a marked increase in glucose, ammonia and urea levels but no change in ketone body concentration.