Pathogenesis of Streptococcus zooepidemicus infection after intratracheal inoculation in llamas

Objectives-To test whether generalized Streptococcus zooepidemicus infectio n could be induced by intratracheal inoculation in Ilamas and to characteri ze this infection. Animals-6 test and 3 control Ilamas. Procedure-Test Ilamas received 1 of 3 dosages of S zooepidemicus by intratr acheal injection, whereas control llamas received sterile culture medium. P hysical examination variables and results of clinicopathologic analyses of blood, peritoneal fluid, and tracheal wash fluid were compared in test llam as between, before, and during the development of bacteremia and with contr ol Ilamas. Bacteriologic culture was performed on all collected body fluids and tissue specimens that. were collected at necropsy. Tissue specimens th at were collected at necropsy were examined histologically. Results-infection induced fever, anorexia, and signs of depression. Five of 6 infected Ilamas developed specific signs of inflammation in the thorax o r abdomen, bacteremia, neutrophilic leukocytosis with toxic changes and hig h band neutrophil cell counts, hyperfibrinogenemia, and high peritoneal flu id WBC counts and protein concentrations. On development of bacteremia, lla mas had significant decreases in serum iron (from 118 +/- 25 to 6 +/- 4 mug /ml) and increases in serum glucose (from 131 +/- 5 to 253 +/- 48 mg/dl) co ncentrations. Conclusions and Clinical Relevance-Streptococcus zooepidemicus spreads rapi dly to other body compartments after intratracheal inoculation in Ilamas. F ever, anorexia, and signs of depression are the most consistent clinical si gns, although other signs are possible. Clinicopathologic analysis of body fluids yields evidence of inflammation. infection by S zooepidemicus can be proven by bacteriologic culture of body fluids before death or of tissue s pecimens after death.