~ others took sick, dying at the rate of 3 ‘to 4a day. Less than thre 
| At the autopsy the abdomen was carefully laid open by first removing the skin and 
"way are not deprived of their power of motility, which is one of the important. 
young pigs, awning € Fiotn 50 146: 100 Free “Mest of ant h 
"purchased i in the city markets. At this same time 20 boar pigs 
‘castrated. Within two weeks these began to die, and soon afte 
weeks after the first deaths only 67 remained out of the 119. Ad 
the end of the year only about a dozen were alive out of the entire 
herd. These may have acquired an immunity. 
The animals were keptin penson the top of a low hillock, sheltered 
- from the eee by large boxes. They were swill-fed, and this may piss 
account for their feeble resistance to the disease. In most of them 
the feeding had induced a cirrhosis of the liver, with softening of the y 
_ parenchyma. The origin of the disease could not be traced, as the 
animals had come from various quarters. The city markets had — 
proved themselves the source of disease in several purchases of pigs’ 
for experimental purposes. It is barely possible that the disease was, _ 
erated during the operation of castration by the instruments — 
use 
The autopsy and bacteriological notes of the individual cases of : 
this outbreak will be reserved for the report of the Bureau for 1887, — 
-A brief summary of all the cases, however, will be given, together with 
some interesting observations and deductions. : 
The spleen and lungs were the only organs upon which bacteriolog- i 
ical observations were made: 2 
a 
(en 
In making cultures from the spieen the following method was usually aden’ 
then cutting through the abdominal muscles with flamed instruments. The fla , 
laid back brought into view the spleen not touched as yet by any instrument. t Be 
was then drawn out with flamed forceps, severed from its attachments with flamed 
scissors, and placed in a large bottle plugged with cotton wool and previously sub-_ Me 
jected to a temperature of 150°-160° C. for three hours. In this way it wastakento 
the laboratory, and either immediately examined or ke +pt in the refrig er ator below 55° 
F. over night. In making cultures the spleen was placed on a sterile glass support ~ 3 
and the surface thor oughly charre:] with a red-hot platmum spatula. This wasal- 
ways done, although usually unnecessary, when we consider the momentary ex- ~~ 
posure to the air in transfer ring the spleen from the abdomen to the bottle. It may, ~ 
however, destroy any bacteria “which have entered the peritoneal cavity through 
ulcerations since. In chronic cases, cocci resembling those of suppuration are not oF 
infrequent in the peritoneal fluid. Through this charred area an incision or rent was ~ 
made and a platinum wire or loop intr oduced with which a tube of gelatine or beef — 
beef infusion was inoculated. When roll cultures were made a minute bit of uv 
pulp was torn away from beneath the charred portion and stirred about in the lique- — 
fied gelatine. From this usually a second tube was prepared. Experience of past — 
years had shown that frequently this is not sufficient to insure the fertility of the — 
cultures. In chronic cases, with spleen but moderately enlarged, hog cholera bac- : 
teria arefound in very small numbers. Insuch cases, bitsof spleen are cutoutfrom 
the charred area with flamed scissors and transferred to tubes of gelatine or beef °. 
infusion with or withont peptone. Such cultures rarely fail. It might be supposed © 
that the chances of accidental contamination are very great in this process. But . P 
a long experience with spleens of healthy animals, and with organs in the study of 
other diseas ses, have demonstrated the entire safety of this proce.ure. Salmon cult- % 
ure tubes, with bits of organs of healthy animals in the bottom covered by nutrient — 
liquids, have remained sterile for months in the laboratory. At present the Esmarch 
tube or roll culture is perhaps best in most cases. ’ 
Tn nearly all the.cases examined both liquid and gelatine cultures were made. —_ 
The former permit a diagnosis on the following day, while the latter require at least f 
two days, usually three or four. before a reliable diagnosis can be made. The cult- 
ures were always examined aE aea. in a hanging drop, as the bacteria in this *|- 
a 
i 
1a 
diagnostic characters. Stainin g cultures was fr equentl) y resorted to, but itadds little __ 
information to that gained by a careful examination of the hanging drop. When 
gelatine cultures were examined, the bacteria were always mixed with some sterile — 
beef infusion to bring out their motility. ce 
