LOUPING-ILL 675 



The liquid in the peritoneal cavity (or within the lining 

 membrane of the belly) sometimes swarmed with the large 

 bacillus, and was turbid. In the clear liquid, in which only a 

 few organisms are present, turbidity developed in twenty- 

 four hours. Turbid liquid inoculated subcutaneously into a 

 healthy sheep, usually kills it in a few hours, after much 

 swelling of the inoculated limb. A little acetic acid simul- 

 taneously injected enhances the action of the bacillus, as it 

 does that of black-quarter. The bacterial character of the 

 disease was definitely established by repeated inoculations 

 with this liquid or with a culture of the bacillus found in it. 

 It was then discovered that in certain fatal cases the bacillus 

 sometimes swarmed in the intestine, where the tissues and 

 cavities of the body were free ; and also that, after being 

 taken in by the sheep with its food, it might multiply and 

 be evacuated in quantity with the dejecta without injuring 

 the animal. Except during the louping-ill season, the blood 

 of a healthy sheep destroys the bacillus when it reaches it, 

 but at spring-time it grows freely in the blood. Chronic 

 cases are brought about by the slow poisoning which 

 supervenes when the resisting power of the blood is partially 

 lost and the invasion of the cavity becomes gradual. 

 " Nervous symptoms are then manifested." By the passage of 

 the organisms along the intestine without doing injury, the 

 sheep are believed to be rendered immune, " so that when the 

 period of danger arrives, they fail to take the disease." 

 Sheep not thus " prepared have little power of resisting the 

 passage of the organism into the peritoneal cavity, and con- 

 sequently many fall victims to the disease," a fact which 

 accounts for the large death-rate among lambs and hoggs, 

 and the excessive mortality among sheep brought in spring 

 from clean to foul ground. This is not an infectious disease, 

 and few, if any, sheep take it a second time. 



Preventive means. Subcutaneous inoculation of their 

 bacilli in this group of diseases (specially in the case of 

 anthrax and louping-ill) "was found to be uncertain and 

 unsatisfactory . . . sometimes ending in the death of the 

 animal." "The results of 'drenching' or introducing the 

 organisms by the mouth, proved eminently satisfactory," 

 except at those times of the year " when the animals are in a 

 susceptible condition," as "the disease may then be 



