Streptothrix Actinomyces, Bollinger (1877). 



ACTINOMYCES BOVIS; BAY-FUNGUS; STEAHLENPILZ {Oerm.). 



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 laclsing" 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 cultv/re. — 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. Oover-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. 



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