504 REPORT OF THE COMMISSIONER OF AGRICULTURE. 



appeared to us in cover-glass preparations or in cultures. In his first 

 co.nnnunication on rougct, Pasteur speaks of tlie microbe as fatal to rab- 

 bits and sheep, but not to fowls. Having satisfied ourselves that it 

 killed rabbits, but had uo effect on fowls, two iambs were inoculated 

 December 31 in each thigli, 'No. 1 with 2'^^'=, Ko. 2 with 1"^% of a liquid 

 culture from tiie spleeu of pig No. 112, now nineteen days old. On Jan- 

 uary 3 the teufperaturc of No. 1 had risen to lOiJ^o F. In both there was 

 considerable stiffness in the hind limbs, no desire for food. No. 2 was 

 killed January 13, after having almost recovered. At tlie places of in- 

 oculation small abscesses had formed. The neighboring lymphatics 

 were enlarged. The viscera seemed intact, excepting the spleen, which 

 was dotted witli numerous small red patches resembling extravasations. 

 A bit of tissue therefrom contained uo bacteria. 



'J'lie otlicr iamb was also nearly recovered. On each thigh two small 

 abscesses had formed. 



A calf was inoculated hypodermically at the same time with 4<=° of the 

 third liquid culture from the spleen of pig No. 114. Its tem[)erature 

 rose from 103° to 100° F., wliich it reached January 2, when a swelling was 

 ]ierceptiblo in front of the shoulder where the injection had been made. 

 The temperature slowly fell afterward. The animal was killed for an- 

 other puri)ose January 13. The swelling, as large as a hen's egg, was 

 found to implicate the muscular tissue into which the needle no doubt 

 had penetrated. When incised, an irregular cavity was found withiu 

 the muscular tissue lined with a soft pidtaceous mass, arising from ne- 

 crosis ol the muscle substance. A superflcial lymphatic ghand near by 

 was considerably enlarged. 



THE EACTERIUM OF SWINE PLAGUE. 



In at least twenty-five cases of undoubted swine plague, bits of spleen 

 tissue, when spread out in a thin layer on a cover-glass, dried and stained 

 in some aniline color, were found to contain the same microbe in greater 

 or less abundance* (Plate II, Fig. 1). When stained for from one to two 

 minutes in an aqueous solution of methyl-violett and examined with a 

 Zeiss y^ houiog., they appear as elongated ovals, chiefly in pairs. The 

 greater number present a center paler than the periphery. This may bo 

 due to a greater density or staining capacity of the peripheral portion. 

 The darker portion is not localized at two extremities as in the bacteria 

 of septic;Timia in rabbits, but is of uniform width around the entire cir- 

 cumference of the ovah The length of an oval in balsam preparations 

 is about 1.2 to 1.5 micromillimeter; its width, .G micromdlimeter. Oc- 



* Dnrino; tho past yearinucli time and laborwero spcutiu examiuiug sections inado 

 from intestiual ulcers, enlarged lymphatics, and hepatized hiiig tissue. Tho nlccrs 

 contained, as might have heeu expected, various forms of organisms. Evcu iu tho 

 deeper portions away IVom the necrosed regions no two nicers Avero alike as regards 

 the bacteria found tjicrein. Sometimes micrococci would be found in abundance iu 

 the inflammatory infiltration. At other timeslong, slender filaments would fill up the 

 adjacent blood vessels and extend into the healthy area. Ova from the inchoccphahis 

 v;eve quite constantly foundan the base of the ulcer; some were imbedded among tho 

 •>ell"]ar elements near tho edge of the tilcer. Sections of enlarged lymjdiatic glands 

 showed an engorgement of the lympli sinuses with blood corpuscles. Bacteria were 

 absent. Sections of lung-tissue were equally negative or contradictory. As the nia- 

 torial examined came from chronic cases the result need not be very surprising after 

 what has been stated concerning the presence of the bacterium of swine plague in tho 

 spleen in acute and chronic cases. It is our intention to subject the material ob- 

 tained from acute cases to a thorough microscopic examination from which better ro- 

 rtults may bo expected. 



tThe bacterium from liquid cultxires when stained with aniline water, methyl-vio- 

 5)6t, and decolorized with iodine according to Oram does not retain the stain well. 



