The presence of endotoxin activity in cases of experimentally-induced heartwater in sheep.

The presence of endotoxin was examined in 5 sheep with experimentally-induced heartwater. Two peaks in endotoxin levels were recorded in 4 out of the 5 sheep during the acute stage of the disease. The 1st peak coincided with or occurred shortly after the febrile reaction (over 40 degrees C). The 2nd peak occurred 3-5 days after the 1st, and in 2 sheep this 2nd elevation in endotoxin levels was associated with severe clinical signs (rapid and laboured breathing, cyanosis and recumbency), and 1 of the 2 sheep died on the day of the 2nd elevation. Both endotoxin peaks were of short duration and levels had decreased in the 24-h follow-up samples.