Streptothrix Actinomyces, Bellinger (1877). 



ACTINOMYCES BOVIS; RAY-FUNGUS; STRAHLENPILZ (Germ.). 



ORIGIN. Occurs in actinomycosis or lumpy-jaw in cat- 

 tle, hogs, horses and in man. It probably leads a sapro- 

 phytic existence on plants, etc. 



FORM. It gives rise to nodules which consist of a 

 whorl of mycelial-like, multiple branched threads. These 

 radiate outward from a central point and become club- 

 shaped. In pure cultures only slender, wavy threads are 

 formed. The club-shaped or swollen ends which are usually 

 present in tissues are lacking, unless the organism is grow- 

 ing deep in gelatin or in blood-serum. The club-shaped 

 ends are the result of degenerative changes. In other 

 words, they are involution forms due to a gelatinization of 

 the cell-wall. 



ANILIN DYES. It stains readily with carbolic fuchsin; 

 also by Gram's method. 



GROWTH. Develops somewhat slowly, requiring several 

 days in the incubator. It can, .however, grow on various 

 media even at the ordinary room temperature. Although 

 usually yellowish it may take on a brick-red color. 



Streak culture. On agar, the growth begins as minute, isolated 

 colonies which slowly enlarge, forming thick, convex, glistening, yel- 

 lowish, opaque masses. The colonies are exceedingly hard and for 

 examination should be crushed between two glass slides, previously 

 sterilized by passing several times through the flame. Cover-glass 

 preparations are then made and stained in the usual manner. 



In bouillon the growth develops on the bottom and does not cloud 

 the liquid. 



OXYGEN REQUIREMENTS. Said to grow best in the ab- 

 sence of air, but grows very well on the surface of agar. 



TEMPERATURE. It grows best at or near that of the 

 body. 



PATHOGENESIS. In rabbits, intraperitoneal injection of 

 the pure culture is said to produce typical actinomycotic 

 nodules on the peritoneum, mesentery, intestinal walls, etc. 



The disease is recognized by the presence of small yel- 

 lowish granules in the pus which is derived from the tumors. 

 The granules when examined with a No. 3 objective will 

 show the typical stellate growth, the hyphae of which have 

 club-shaped ends. 



Infection results from the plant food on which the or- 

 ganism is growing. Several varieties of actinomyces have 

 been described; can be distinguished only by culture. 



416 



