FaralysLs in Horses and Coivs. 203 



that Avliile oecasioiiall}- on farms in South Australia the disease may 

 occur in both cattle and horses, it more frequently happens that 

 the one or" the other class of animal is alone affected. Why this is 

 so will, of course, be a matter for further investigation. 



Though much has been written regarding the symptoms observed, 

 especially in the cow, and to some extent in the horse, in this 

 artitlf 1 propose to confine myself to I'ecording what I have per- 

 B(.inallv ol)served and ascertained from owners of the affected stock. 



Symptoms in Cow. 



Usually the first symptom of illness observed by the dairyman is 

 either a severe diminution, or almost complete cessation, of the 

 milk supply in a cow which at the previous milking has yielded her 

 normal quantity. 



It is more than probable, however, that a careful observer might 

 detect some symptom prior to this, especially if close attention were 

 paid to the animal when feeding or at rest; but in any case, such 

 abnormality is liable to be overlooked until the milk yield is 

 affected. Even then other symptoms are by no means very definite. 

 Kumination is often suspended, but this is not unusual in many 

 cattle diseases. Often it is intermittent. The most definite and 

 probably most characteristic symptom at this stage is a peculiar, 

 slow and very persistent movement of the jaw, not the ordinary 

 movement which occurs during either chewing food or cud, but a 

 slow up and down movement, with little, and often no, lateral 

 niovement of the lower jaw. This movement seems to be almost 

 involuntary; it will cease Avhen the animal's attention is distracted, 

 and is resumed again latei- on. The head is held somewhat straighter 

 than normal, and this becomes more pi-onounced during the progress 

 of the disease. The expression is peculiar, it may almost be 

 termed wistful and enquiring. Inattentiveness to smroundings is 

 obsei'ved, and the animal is generally seen apart from the herd. 

 No attempt to eat or drink is made, but whether at this stage 

 because the animal knows she can only chew and swallow, if at all, 

 with difficulty, or through experience of ineffectual attempts, or 

 thi'ough intuition, I have not been able to determine. There is, 

 however, from the first. I think, but little appetite, tliough it may 

 not have entirely disappeared. In the very mild cases, or cases 

 which progress slowly, a little water may be swallowed, but with 

 great difficulty. In one instance I observed a cow hold her mouth 

 in a bucketful of water for ten minutes, and only succeed in drink- 

 ing half the contents. On another occasion I observed a cow whicii 



3.^ 



