MIRAGLIA AND BERRY 



colonized with the Giorgio strain with great facility. Thus, nasal 

 staphylococci which are mainly coagulase- negative are found to 

 persist unabated in all 228 mice studied. 



Nasal cultures also revealed that in the winter only coagulase- 

 negative strains were harbored, but that in the summer a low in- 

 cidence of positive strains was also evident. In a group of mice from 

 which coagulase- positive strains were isolated from the tissues for 

 the first time, it was found that the stools contained only coagulase- 

 negative staphylococci, whereas also for the first time coagulase- 

 positive organisms were isolated fromthe nose. Coagulase- positive 

 strains have never been isolated from the tissues of mice which had 

 coagulase- negative nasal flora. Thus, a correlation may exist be- 

 tween the nasal flora and the organisms isolated from deep tissue 

 as secondary invaders in cold stressed mice. 



Effect of acid water treatment on the per cent of salmonella 

 carrier mice with feces positive for salmonella. It is reasonable to 

 assume that since hydrochloric acid treatment eradicates staphylo- 

 cocci from the gut, the population of other members of the intestinal 

 microflora may be likewise altered. This phase of the study has not 

 been actively pursued, but results from a preliminary experiment 

 using 40 mice show that the carrier rate for salmonella was reduced 

 from 80 per cent to 5 per cent, P<.008 (Wilcoxon, 1949), in 24 hours 

 by using the acid water treatment. This indeed appears to be a dra- 

 matic reduction, but owing to the inherent shortcomings of the sam- 

 pling method and the obvious danger of generalizations based on a 

 single experiment, a more definite statement concerning the efficacy 

 of this treatment for carrier mice must await more intensive studies. 



DISCUSSION 



Host defenses are breached in animals maintained in the cold. 

 The two levels of cellular defense, one comprised of the more peri- 

 pheral wandering phagocytes and the other the deeper fixed tissues 

 of the reticuloendothelial system (RES), are each affected by cold or 



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