218 BACTERIA PRODUCING DIPHTHERITIC INFLAMMATIONS 



strictly anaerobic properties are shown by the fact that the culture 

 never reaches the surface of the serum medium. In the condensed 

 water of serum agar the growth forms a grayish-white film or pellicle 

 and a sediment of the same color. When grown in bouillon or 

 milk a smell of cheese is given off; the fluid media then give the 

 indol reaction. The organism is frequently found in the intestines of 

 herbivorous animals, particularly the hog. Pure cultures cannot, as 

 a rule, be obtained directly from the lesions, because the organism is 

 rarely present in that condition, but is usually mixed with other patho- 

 genic or saprophytic organisms. The* method of procedure consists 

 in inoculating the material subcutaneously into a rabbit. A very 

 hard inflammatory induration is then formed at the site of the in- 

 jection, where the tissues subsequently became caseous and necrotic. 

 The necrophorus bacillus at first multiplies locally, and afterward 

 enters the general lymph and blood circulation, leading to the forma- 

 tion of metastases in the internal organs, particularly the lungs and 

 the liver. The rabbit generally dies in less than two weeks, and 

 anaerobic cultures can be made from the internal metastases, which 

 usually contain the organism in pure culture. The disease also occurs 

 spontaneously in rabbits, starting as an infection of the face. 



BACILLUS DIPHTHERIA AVIUM. 



Occurrence and Pathogenesis. A highly contagious disease char- 

 acterized anatomically by diphtheritic inflammations of the mucous 

 membranes of the head occurs among pigeons, domestic and prairie 

 chickens, turkeys, and other fowl. The diphtheritic pseudomem- 

 branes are found in the mouth, pharynx and nose, and its accessory 

 cavities, less frequently in the larynx, trachea, bronchi, and intestines. 

 In the latter the cecal pouches are sometimes completely filled 

 with the diphtheritic membranes. The cause of the disease is a 

 short bacillus which was first found by Loeffler in diphtheria of 

 pigeons. It was, accordingly, called Bacillus diphtherise colum- 

 barum. Later, Moore and others found the same bacillus in 

 chicken diphtheria, and it is now generally known under the more 

 general term of the bacillus of bird diphtheria (Bacillus diphtherise 

 avium). 



Morphology and Staining Properties. The organism is a short bacillus, 

 not motile, and does not form spores. It stains in a bipolar manner 

 with the watery anilin stains, and is Gram negative. 



Cultural Properties. It grows both in the presence and absence of 

 oxygen. On gelatin, which is not liquefied, a grayish-white transparent 

 growth composed of finely granular colonies appears first, later the 

 growth becomes white and opaque. On agar the growth is similar, 

 but first slightly bluish, then white and opaque, as on gelatin. Bouillon 

 becomes first uniformly cloudy, later a somewhat transparent white 



