PERITONITIS AND BACTEREMIA IN MICE 



For bacterial counts, blood samples of 0.02 ml were drawn with 

 the same type of S3n:ingeprefilled with 0.18 ml of 0.85 per cent NaCl 

 solution after cutting the dorsal vein of the tail thoroughly cleaned 

 with 70 per cent ethyl alcohol. The resulting 1:10 dilution was spread 

 over a 3 per cent horse blood agar plate. After incubation overnight 

 at 37° C, the bacterial growth was roughly estimated as "(+)" (1-5) 

 colonies "+" (6-50), "++" (51-500), or "+++" (more than 500). In the 

 elimination studies, appropriate dilutions of the samples were made 

 to permit a precise count. 



Fecal specimens were taken from the rectum with a 2 mm plat- 

 inum loop and spread on plates as above. 



At autopsy, fecal specimens weretaken as described above, blood 

 samples from heart puncture were cultured as was described for the 

 tail blood, and peritoneal fluid was collected with a cottom swab from 

 the abdominal cavity and directly spread on a blood agar plate. 



RESULTS 



Influence of Hypothermia on the Intestinal Flora 



As the main source of endogeneous bacteremia is likely to be the 

 intestine, the composition and density of the aerobic fecal flora were 

 studied after various periods of hypothermia. The results of fecal 

 cultures are presented in Figure la; point of time is represented by 

 numbers of cultures ranging from 109 to 29. Within the colif or m 

 group, the proportions of E, coli, A, aerogenes, and Paracolo- 

 bacteria were not significantly altered during the experiments. 

 Small numbers of bacteria of other species not represented in 

 the figure were observed but are disregarded here for simplicity. 

 It is evident that the intestinal flora as represented by fecal cul- 

 tures was not altered significantly in prolonged hypothermia. 



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