﻿278 



STRONG. 



Series 15. — Experiments with rats. 



One 48-hour agar culture "Pest Virulent" (guinea pig number 1296) sus- 

 pended in 5 cubic centimeters bouillon; a 5 cubic centimter needle was dipped 

 in this suspension and then thrust beneath the skin near the root of the tail of 

 each animal. All the rats except the two numbered 1348 and 1353 received intra- 

 peritoneally, just prior to being stuck with the infected needle, serum from human 

 cases or animals previously vaccinated against plague. 



Animal 

 No. 



Scrum intraperito- 

 neally. 



How inocu- 

 lated. 



Result. 



Autopsy and remarks. 



1342 



5 cc. of serum 



Stuck with 5 



Dead after 



Fair number of pest bacilli in smears 





from case 14. 



cc. needle. 



4 days. 



from spleen. 



1343 



2 cc. of serum 

 from case 14. 



do 



__ _do _ _ 



Do. 







1344 



2.5 cc. serum 



do 



Dead after 



Numerous pest bacilli and post-mor- 





from case 15. 





2 days. 



tem invading bacilli in smears from 

 spleen. 



1345 



do 



. do 



Dead after 



Numerous pest bacilli in smears from 









5 days. 



spleen. 



1346 



5 cc. of serum 



do 



Dead after 



No bacilli found in smears from spleen. 





from animal 





3 days. 



Innumerable from tissues near point 





No. 1965 * 







of inoculation. 



1347 



do 



do 



do 



Very few bacilli found in smears from 

 spleen. Innumerable near point of 

















inoculation. 



1348 





do 



do 



Innumerable pest bacilli in smears 











from the spleen. 



1349 



5 cc. serum from 



do 



Dead after 



A fair number of pest bacilli in smears 





animal No. 





4 days. 



from spleen. 





1967. t 









1350 



do __ 



. do 



Dead after 

 2 days. 



No pest bacilli seen in smears from 

 spleen. A few post-mortem invad- 

 ing bacilli present. 



1351 



2.5 cc. serum from 



__'_._do 



Dead after 



A few pest bacilli in smears from 





animal No. 





3 days. 



spleen. 





1967. 









1352 



__ _ do 



do 



Dead after 



Fair number of pest bacilli in smears 









4 days. 



from spleen. Numerous post-mor- 

 tem invading bacilli. 



1353 





. do 



Dead after 



Few pest bacilli in smears from spleen. 









3 days. 





♦ Number 19G5 had been previously inoculated intravenously with 5 cubic centimeters Haffkine's 

 prophylactic. 



t Number 1967 had been previously inoculated intravenously with 1 cubic centimeter autolyzed 

 product digested from 20 milligrams of the strain "Pest Virulent." 



