362 VETERINARY LECTURES 



K.G., and reported that — ' The disease has a seasonal and local epidemic 

 character,' and that ' the malady strongly pointed as belonging to the class 

 of infectious diseases, and was, apparently, communicated from one animal to 

 another.' Yet he says : ' The causa causans of the disease is contained on 

 or in the soil '; also, ' When the disease prevails, a fence between one sheep 

 farm and the next is occasionally found to be the boundary between the 

 infected and non-infected area.'' Now if the soil be the cause of the first 

 case, why should it not be the cause in all the succeeding cases that 

 are susceptible to its influence, seeing that as many as from seven to 

 ten sheep will die in twenty-four hours ? My view is that louping-ill 

 is allied to certain enzootic diseases, and, like red-water in cattle, is 

 common to certain localities and soils from the same common cause. 

 I think it is due to the indigestible and innutritious nature of the 

 decaying grasses, producing derangement of the digestive organs and 

 deterioration of the blood, and this in turn acts on the nerve centres, 

 inducing a want of co-ordination of movement, hence trembling and 

 imperfect action of the limbs. Or the complaint may be from some 

 reflex nervous action, arising from the irritating effects of the 

 innutritious herbage on the stomach, producing the symptoms peculiar 

 to the malady. Professor Hamilton, M.B., F.R.C.S.E., of Aberdeen, 

 and his colleagues, who have been investigating some of the diseases 

 affecting sheep since 1901, in their report to the Departmental Com- 

 mittee of Agriculture, state that louping-ill in sheep, like braxy 

 {par. 329), was due to the presence of a coarse-looking, rod.-shaped, 

 spore-bearing organism, named by the professor Bacillus chorea 

 paralytica ovis, Hamilton, found in the fluid in the peritoneal cavity — 

 cavity of the belly — and also in the intestines, and that from the 

 numerous experiments conducted by them the bacteria or their 

 spores were taken up in the food into the alimentary canal, wherein 

 they multiplied and were evacuated in quantities with the excre- 

 ment, and by these means the pastures were contaminated, while at 

 certain periods of the year (July and August) the blood of the sheep 

 had a protective influence, but in spring (April to June) it lost this 

 property, and the sheep were rendered liable to be attacked with 

 louping-ill ; and also that a soup prepared from the disease-producing 

 fluid found in the cavity of the belly, when administered to the sheep 

 in the autumn months, had a tendency to prevent the disease. 



