EN
The examinations were done on 7 healthy Polish ponies from 1.5 to 14 years of age. The experimental animals were intravenously injected Escherichia coli LPS at a dose of 0.1 µg/kg b.w. Clinical observations and blood collection for laboratory examinations from the external neck vein were done just before endotoxin injection and then for 8 hours at one hour intervals and after 24, 48, 72 and 96 hr. from endotoxin application. All horses were examined routinely clinically (rectal temperature, pulse, respiration rate) and hematologically (total number of leukocytes, differential leukocyte count). Phagocytic activity of neutrophilic granulocytes was evaluated on the basis of the percentage of phagocytic cells (KF) and the phagocytic index (IF) using a standard Staphylococcus aureus strain. Moreover, the nitrotetrazolium blue reduction test (NBT) was done by a microquantity method. Clinical observations and hematological examinations in the experimental animals were typical for endotoxemia of horses. It was also found that LPS of E. coli at the administered dose stimulates unspecific immunity because it increases the value of KF, IF and NBT during the whole period of experimentation.