SCHMIDT 



ciiliar things here in the bacterial picture. For instance, we see 

 a rather rapid increase in the psychrophiles beyond what you 

 can get in a test tube. You know how slowly psychrophilic or- 

 ganisms grow at, say, 4° C. It takes several days to get much 

 of an increase, but in the squirrel, after he hibernates for a 

 couple of days you find approximately a six log increase and, 

 at the same time, you may observe perhaps a three log de- 

 crease in the count of E. coli. I have no explanation for this 

 whatsoever, 



WALKER: Could this be a matter of competition in the in- 

 testinal tract? Could the conditions be such that one has a greater 

 advantage than the other and E. coli is crowded out? 



ANDREWES: I don't see why E. coli should actually die. 



SCHMIDT: They won't reproduce at these low temperatures. 

 They have several things working against them, whereas the 

 psychrophiles have everything working their way, as it were. 

 This is the temperature at which the psychorphiles can re- 

 produce, and at the same time, body defenses are rather im- 

 mobilized so that they can grow unabated. 



WALKER: Yes, the pH may change and there are all sorts 

 of things to which E. coli may be susceptible. 



SCHMIDT: Well, I have tested for antibiosis by the plate method. 

 It was not an exhaustive study, and although I haven't seen any 

 evidence of this as yet, it is one of the things that certainly 

 should be considered. Also the moisture content of the intes- 

 tinal contents changes somewhat. In addition, there is a lot of 

 mucus secreted into the intestine, which probably serves to 

 protect the lining during these periods, and this may have an 

 effect on the bacteria and also the virus. 



ANDREWES: My second question refers to Dempster's story 

 about the enterovirus multiplying. It would seem from what 

 you have told us that one might infer that this virus is growing 

 at a temperature lower than any other viruses do grow, so one 

 might suspect that any growth there is might occur during these 



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