TYPES OF INFECTION 37 



the tubercle bacillus; (c) the actinomyces fungus; (d) the 

 necrosis bacillus. 



They are named after the organism causing the infec- 

 tion: Pyobacillosis mammae, tuberculosis mammae, actino- 

 mycosis mammse, and necrobacillosis mammse, or udder- 

 pyobacillosis, udder-tuberculosis, udder-actinomycosis, and 

 udder-necrobacillosis. 



Complex Udder-infection or Mixed Infection. — 

 The mixed infection is caused by two or more types of 

 bacteria. 



The bacteria which cause this disease are of the same 

 type that cause the simple infection. 



The mixed infection may start originally as a primary 

 mixed infection. 



Usually, however, it is .originally a simple infection and 

 becomes complex or mixed later through secondary infec- 

 tion (secondary milk-infection). 



