HEMOSTASIS IN COWS WITH ENDOTOXIN-INDUCED MASTITIS

Hemostasis was evaluated in cows with experimentally induced endotoxem ia and mastitis, caused by intramammary infusion of endotoxin (1 mg) d erived from Escherichia coli. Hemostatic tests included prothrombin ti me; activated partial thromboplastin time; thrombin time; fibrinogen, fibrin(ogen) degradation products, and platelet concentrations; and an tithrombin-III and plasminogen activities. Significant alterations wer e observed in the mean values of most analytes (prothrombin time was i ncreased; thrombin time was increased with subsequent decrease; activa ted partial thromboplastin time. fibrinogen concentration, plasminogen activity, and platelet concentration were decreased; and antithrombin -III activity and fibrin(ogen) degradation products concentration were unchanged) at 1 or more postchallenge sample collection times (3, 12, or 24 hours) after endotoxin administration, compared with mean value s obtained from samples prior to endotoxin administration. These data indicated activation of hemostatic mechanisms, initiated either direct ly by endotoxin or by inflammatory mediators released or produced in r esponse to endotoxin infusion.