674 Progressivi' Bull)ar Paralysis. 



sis (see page 215). All these forms have been dealt with in th-e 

 chapters devoted to the particular subjects. 



There appear to be other diseases than those mentioned 

 above that occur in animals, and are associated with bulbar 

 paralysis. Stietenroth observed a bulbar paralysis terminating 

 fatally in seven to twelve days in three horses, the exact nature 

 of which was not determined. Thomassen mentions the occur- 

 rence in Belgium and Holland of a contagious disease among 

 young horses associated wdth suddenly occurring difficulty of 

 masticating and swallowing, and paresis of the limbs. Histo- 

 logical examinations revealed no alterations save that there 

 was a reduction in the number of ganglion cells in the neigh- 

 borhood of the nuclei of the hypoglossal, glosso-pharyngeal and 

 vago-accessorius nerves and there was chromatolysis, vacuoli- 

 zation and marginal disposition of the nuclei. Thomassen iden- 

 tifies the disease with the progressive bulbar paralysis ob- 

 served in Belgium, but owing to essential differences in the 

 course of the disease, it should not be considered as the same. 

 From time to time, cases are recorded in which paralysis of the 

 nerves of the bulb is an outstanding feature. Little definite 

 information can at the present moment be given with regard 

 to these and similar diseased conditions. The principal con- 

 ditions included under the term are enceplialo-myelitis of va- 

 rious types, diseases of the peripheral nerves, and poisoning. 



Literature. Dexler, Ergebn. d. Path., 1896, III, .507 (Lit.).— Doderlein, 

 W. f. Tk., 1905, 83.— Stietem-oth, B. t. W., 1899, 265.— Thomassen, Monh., 190.3, 

 XIV, 1. 



(b) Progressive Bulbar Paralysis. 



Occurrence. There are observations to show that progres- 

 sive bulbar paralysis occurs in the horse as an independent 

 condition (Lagrange, Stockfleth, Gerard, Degive, Cadeac, Tho- 

 massen, Frohner). The disease appears to have a tendency to 

 break out sporadically every year in the northern parts of 

 Belgium. Isolated cases have been recorded by Cadeac in 

 France, Frohner and Rosenfeld in Germany. 



Etiology. Belgian authors and Thomassen are inclined 

 to think that the cause of the disease is an intoxication due to 

 white beets, there being no evidence that it is due to an infec- 

 tion. It is still unknown whether the disease actually involves 

 the medulla oblongata or the nerves originating from it. 



Symptoms. Clinically, the disease is characterized by a 

 gradually progressing bilateral paralysis of the bulbar nerves. 

 There is difficulty in swallowing in every case. The animal 

 takes food greedily, chews it for a long time, but swallows only 

 a part or none at all, the food returning partly through the nose 



