406 BACILLI IN CHRONIC INFECTIOUS DISEASES. 



In stick cultures in, glycerin-gelatin, the growth resembles an in verted stetho- 

 scope; at the surface a circular, bluish membrane is formed, which is de- 

 pressed in the form of a funnel, while along the line of puncture a slender, 

 yellowish, jagged column is developed. Upon agar, at 36 C., a bluish- 

 white layer is quickly developed. Upon potato the growth resembles that 

 of the typhoid bacillus at first; later a granular membrane is formed; under 

 a low power the granules appear to be formed of intertwined masses of fila- 

 ments. The growth upon blood serum is similar to that upon agar. 



Pathogenesis. Subcutaneous injections in guinea-pigs cause their death 

 in one to two weeks, in rabbits in one to two months, in cats and dogs in 

 two months or more. Death occurs in a shorter time in animals which, have 

 been fed upon cultures than as a result of subcutaneous injections. The 

 animals become very much emaciated and have paralysis of the sphincter 

 muscles. At the autopsy flat or nodular elevations, which are often ulce- 

 rated, are seen here and there upon the mucous membrane of the stomach 

 and intestine ; the mesentery, especially of the small intestine, is hyperaemic ; 

 the mesenteric glands are swollen, as are also the inguinal glands. In the 

 liver and sometimes in the ovary, uterus, and spleen larger or smaller nod- 

 ules are seen. 



60. BACILLUS OP NOCARD. 



Obtained by Nocard (1888) from pus collected from the superficial ab- 

 scesses in cattle suffering from a chronic infectious disease which prevails 

 especially upon the island of Guadaloupe known as " farcin du boeuf"; 

 Ger. "Wurmkrarikheit." 



Morphology. A long and slender bacillus, about as thick as the bacillus 

 of rouget (Bacillus murisepticus) ; usually seen in tangled masses which 

 consist of an opaque central portion surrounded by long filaments, which 

 apparently give off lateral ramifications. (This description of the morphol- 

 ogy gives rise to the suspicion that the microorganism described by Nocard 

 is a microscopic fungus rather than a bacillus.) According to Nocard, the 

 branching is more apparent than real, and is in fact a false dichotomization, 

 such as is seen in the genus Cladothrix. 



Stains best by Weigert's method ; is decolorized by Gram's method. Does 

 not stain readily with most aniline colors. 



Biological Characters. An aerobic, non-motile bacillus, which does 

 not grow in nutrient gelatin at the room temperature. Grows in the usual 

 culture media at a temperature of 30 3 to 40 C. Forms small oval spores. 

 Is destroyed in ten minutes by a temperature of 70 C. Upon the surface 

 of agar it forms irregular, opaque, yellowish-white colonies, which are 

 thickest at the margin, have a dull, dusty- looking, mammillated surface, 

 and after a time become confluent, forming a thick, wrinkled, membranous 

 layer. Upon potato development is rapid in the form of prominent, dry, 

 pale- yellow plaques. In bouillon whitish flocculi are formed, most of which 

 fall to the bottom, while some float upon the surface, where they form dry, 

 dusty-looking, rounded pellicles of adirty-gray color withagreenish reflection. 

 ^Pathogenesis. The guinea-pig is the most susceptible animal. When 

 injected into th^ peritoneal cavity of one of these animals it produces, in 

 from nine to twenty days, lesions which closely resemble those of miliary 

 tuberculosis. At the autopsy the peritoneu m is found to be covered with 

 nodules, in the centre of which the bacillus is found in tangled masses ; the 

 liver, spleen, kidneys, and intestine are also studded with pseudo-tubercles, 

 but these are only found in the peritoneal coat and not in the parenchyma 

 of the various organs, or in the organs of the thoracic cavity. Intravenous 

 injections give rise to lesions similar to those of general miliary tuberculo- 

 sis, the organs generally containing a considerable number of nodules, in 

 the centre of which_tufts of bacilli are found. In cattle and sheep similar 

 lesions result from intravenous injections, but without causing the death of 

 the animal. The dog, the cat, the horse, the ass, and the rabbit are immune. 

 Subcutaneous inoculations in guinea pigs produce an extensive local abscess, 

 followed by a chronic induration of the neighboring lymphatic glands. 



