Bacteriological Diagnosis. Prognosis. 21 



from a peripheral vein (ear or jugular) as putrefaction sets in later in these parts 

 than in the internal organs. As a result of putrefaction the bacilli change' their 

 form after a time; they become mor^ slender; their plasma does not stain well, and 

 later not at all; at the same time other bacteria and especially anaerobic putre- 

 factive bacteria multiply very rapidly. The capsule of the anthrax bacillus is 

 preserved somewhat longer so that after a time only empty capsules or the remains 

 of plasma envelopes can be seen (See fig. 2 on page 3). They finally become 

 unrecognisable (according to Olt, in the summer time in about 48 hours). Its 

 diagnostic importance, however, should not be overestimated as a capsule may occa- 

 sionally occur on some putrefactive bacteria resembling the anthrax bacillus 

 (Noetzl), and on the other hand sometimes they cannot be demonstrated even on 

 true anthrax bacilli, especially in the blood of horses and carnivorous animals. 



According to Cinca & Fenca the feces of affected animals (sheep and hogs) 

 invariably contain anthrax spores which can be isolated through cultural niethods 

 by a previous heating to 65 °C. This is possible even in cases in which the carcass 

 is already putrid and the examination of the blood gives negative results. 



In the examination of stale blood or material from organs good results may 

 sometimes be obtained by the mucin reaction which was first described by.Weichsel- 

 baum (1892), later by Helm and recently recommended by MacFadyean. This 

 reaction is manifested in smears stained with 1% methylene blue solution by the . 

 appearance of violet or purplish-red granules which are seen near the bacilli and 

 originate from their capsules. 



Positive results are obtained in doubtful cases by the isolation of the anthrax 

 bacillus by the plating method. According to Bongert the bacilli remain active in 

 dried blood for 36 to 50 days, in putrefied dried blood or tissue fluids for a shorter 

 period. However, they retain their virulence on an average of from 8 to 20 days. 

 In carcasses which have lain unopened the results from the examination of smear 

 preparations are uncertain even after 24 hours, while by the plating method they 

 may be demonstrated for 2 or 3 days after death. 



Finally, the diagnosis may be proved by animal inoculations, for which the 

 usual laboratory animals, with the exception of the rat, may be vitilized (to prevent 

 an intoxication only small quantities of the material should be used for inocula- 

 tions; the scarified shaven skin is best adapted for the inoculation of putrid 

 material). 



Suspicious material forwarded for an accurate bacteriological examination is 

 best prepared by spreading the softened pulp of the spleen from 3 to 4 mm. thick 

 on a slide, across each end of the slide a strip of thick cardboard is placed, and 

 another slide is then placed on these pieces of cardboard. . They are then securely 

 tied and forwarded in a box for examination (Kitt, Bongert). Another method 

 consists in breaking a boiled potato in two; the blood or spleen tissue having been 

 smeared on one of the broken surfaces, the pieces are placed together again and 

 the whole forwarded to its destination (Olt). Further, the blood or spleen pulp 

 may be dried on the inner surface of a test tube, or on woolen threads or cotton 

 pads (Heim, Mazzini). 



Jakobsthal & Pfersdorff, as well as Marxer and Eberle, recommend for the 

 above purpose quadrangular pieces of gypsum rods saturated in Loeffler 's bouillon 

 and placed in strong test tubes. Before use they are dipped in pure water, then 

 covered with a thin layer of blood or splenic pulp, placed in the tube, which is 

 packed in a wooden case and forwarded to the laboratory. Inasmuch as the bacilli 

 form spores on the rods in a proper temperature the diagnosis is possible even after 

 14 months. Instead of gypsum rods small pieces of burned bricks are also adapted 

 (Eeinecke), or even better filterpaper rolls about the thickness of the small finger 

 and moistened in water (Schiiller, Grabert). 



Prognosis. Obviously anthrax terminates not infrequently 

 in recovery, although it is hardly possible to estimate the per- 

 centage of recoveries with any degree of certainty. In the 

 course of various outbreaks it is a quite frequent occurrence 

 that some of the animals which were exposed to the infection 

 show an indisposition and fever, but recover completely in 1 

 to 2 days. Such passing affections are probably the result 

 of an -anthrax infection, which, however, is overcome by the 

 energetic resistance of the animal. Toward the end of some 

 epizootics the disease often assumes a subacute form and then 



