290 



FOOT-ROT IN SHEEP 



Fig. 65. 



Bacillus necrophorus (after 

 Mohler) . 



from their organs it can be obtained in pure culture. The 

 time required to kill these animals is usually from four to 



twelve days. 



The period of incuba- 

 tion in small animals is 

 but a few days. In the 

 naturally contracted dis- 

 ease in sheep it is uncer- 

 tain. In cases produced 

 by inoculation of the 

 specific bacillus from 

 three to ten or more days 

 elapse before symptoms 

 appear. 



§ 216. Symptoms. 

 Lameness is the first 

 symptom noted. If ex- 

 amined prior to this, 

 Mohler reports a moist area of the skin just above the horny 

 part of the cleft of the foot. The inflammatory condition 

 extends rapidly to tissue beneath the horny part. There is 

 often a discharge of a thin, purulent fluid. Mohler states that 



the discharge emits a pungent, dis- 

 agreeable odor which is character- 

 istic of this infection. There is 

 emaciation which may be due quite 

 as much to the inability of the lame 

 sheep to procure food as from the 

 y^-c specific action of the bacillus. 

 r&.. The duration of the disease varies 



Fig. 66. JSIecrotic area in from a few weeks to several 

 the liver of a rabbit; C, months. The cases are said usual- 



liver cell, B, inflammatorv i„4.4.i. • irin 



' -^ ,. ^ ly not to terminate fatally. 



zone. A, necrotic center 



(Mohler). g 217. Morbid anatomy. The 



tissue changes are those of a purulent exudative inflammation. 



As the process undermines the horny portion of the hoof it 



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