CCENURUS CEREBRALIS IN CATTLE AND SHEEP, 353 



autumn and winter months. I find, however, that in some 

 districts there is greater prevalence of sturdy in summer. 

 This occurs when, during the hot months, sheep are kept on 

 unenclosed pastures on hills where they must be constantly 

 " herded," whereas during the winter the flock is transferred 

 to enclosed fields, and clogs are more or less removed from 

 them. Sturdy will always be found to prevail on farms with 

 open pastures, where flocks constantly need the guardianship 

 of shepherds and dogs, or on enclosed farms where sheep are 

 fed on turnips, confined daily within limited space, with one 

 or more dogs amongst them. These are the conditions 

 favourable to the development of sturdy, and they are those 

 favourable to the dissemination of tapeworm eggs by dogs, 

 and the penetration of the eggs in the bodies of the sheep. 

 These eggs find a favourable nidus in the cerebral mass of 

 the lamb, and they there develope into the coenuris cere- 

 bralis. 



Sturdy is occasionally confounded with other diseases ; and 

 my attention has sometimes been called by farmers of great 

 experience to a sheep presenting certain anomalous symp- 

 toms, which, though distinctly due to the presence of the 



show that all conditions calculated to favour the healthy and robust 

 state of the sheep will prevent the introduction and development of 

 parasites in the body, not excepting the coenuris cerebralis. Fromage 

 de Feugre declares that when lambs are too fat they are most liable to 

 sturdy ; and Reynal only recently advocates the theory of Huzard, that 

 those lambs become affected with sturdy which are born of ewes that 

 have suffered during pregnancy, or that are naturally weak; and, lastly, 

 that the produce of rams of an enfeebled constitution is very subject to 

 the disease. Many shepherds have observed a connexion between the 

 development of sturdy and the presence of dogs amongst the flocks. 

 Many intelligent farmers have a great dislike to dogs amongst sheep, 

 in the belief that by being worried, the sheep become affected with 

 sturdy. 



VOL. ii. 3 B 



