LUMPY JAW (ACTINOMYCOSIS) 209 



reoccupied within a period of sixty days following disinfection. 

 The methods of eradication of foot and mouth disease as prac- 

 ticed by the United States Government consist of rigid quaran- 

 tine, thorough disinfection and the purchasing and slaughtering 

 of affected and exposed animals after proper appraisement. 



LUMPY JAW (ACTINO-MYCOSIS) 



This is a specific chronic infectious disease caused by a 

 certain fungus (actinomyees) and characterized by the forma- 

 tion of tumorous masses in various parts of the body, more par- 

 ticularly the head. The history of this fungus is not known, 

 but it is thought that it passes a part of its life cycle on certain 

 grasses. The matured fungus has the appearance of a rosette 

 and is commonly called " ray fungus." 



Distribution and Extent. — Actino-mycosis or lumpy jaw is 

 quite prevalent in the United States. The extent of the disease 

 varies in the different states. According to the twenty-fourth 

 annual report of the Bureau of Animal Industry there were 

 slaughtered in establishments having federal inspection, 7,621,- 

 717 cattle, of which 22,742 were found to be affected with 

 lumpy jaw. The actual percentage is even greater, for numer- 

 ous animals affected with this disease are slaughtered where 

 there is no official inspection maintained. 



Source of the Fungus — The fungus which causes the dis- 

 ease is probably most frequently obtained from vegetation, 

 especially wild rye, barley, oats and other grains. Infection is 

 thought to occur most often in animals fed on dry feed such 

 as fodder, straw, or hay. It is questionable as to whether the 

 disease may be transmitted directly from one animal to another, 

 although certain instances have been recorded wherein the infec- 

 tion apparently spread by actual contact. 



The causative fungus may gain entrance to the animal body 

 by way of the digestive tract, the respiratory tract or through 

 the skin. The digestive tract is the most frequent channel of 

 entrance in cattle. Wounds of mucous lining of the mouth, 

 diseased teeth, or the shedding of milk teeth, provide an en- 

 trance for the causative fungus. The upper surface of the 

 tongue, which is often injured by rough feeds, frequently affords 

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