660 



Gid. 



13. Gid. Coenurosis. 



{Drehsucht, Drelikrankeit [German], Tournis [French], Gid, 

 Staggers, Tuntsick.) 



Gid is a chronic disease of ruminants, and especially of 

 the sheep, and is caused by the Coenurus cerebralis, the cystic 

 stage of the Ttenia coenurus. In addition to other symptoms 

 indicative of cerebral disturbance there are very frequently 

 forced movements. 



Historical. The Coenurus cerebralis was first recognized as the 

 cystic stage of a tapeworm by Leske in 1780, and the nature and etiology 

 of the disease by Kuchenmeister in 1853. This was confirmed by other 

 authors at a later date (Haubner, May, Gurlt, Gerlach, Leuckart, Baillet, 

 Flirstenberg), and the Coenurus cerebralis was recognized as the cystic 

 stage of the Taniia coenurus. 



Occurrence. The disease is 

 known in all countries. The sheep 

 is most commonly attacked, and 

 the disease occurs more rarely in 

 cattle and still more rarely in the 

 goat. It is only exceptionally that 

 the disease is met with in the 

 horse, camel, dromedary, ante- 

 lope, rabbit and hare. In wet 

 seasons, the disease among sheep 

 may amount almost to an epi- 

 zootic. Trinchera observed out- 

 breaks among calves, and Bauer 

 among calves and adult animals. 

 Etiology. The Coenurus cere- 

 bralis is a single cyst wdiich may 

 be as large as a hen's egg and is 

 filled wdtli a colorless or pale yel- 

 low liquid. Through the delicate 

 translucent wall one can dis- 

 tingiiish small white specks, the 

 size of poppy seeds or smaller, each of which is an invaginated 

 scolex. These are, as a rule, arranged in smaller or larger 

 groups (fig. 91). 



01. Cwinirus cerebralis 

 iiral size. 



Nat- 



The cysts develop from embryos set free in the stomach from eggs 

 of the taenia. Having bored their way through the wall of the stomach 

 or intestine by means of their hooks, the embryos are apparently car- 

 ried by the blood-stream to the cranial cavity of their new host, where 

 they lose their hooks and become converted into small cysts. Excep- 

 tionally, they are carried into the vertebral canal. Witli further devel- 

 opment the scoHces are formed, thus producing the typical cysts. 



