442 DISEASES OF THE HORSE. 



BLEEDING SKIN ERUPTIONS, OR DERMATORRHAGIA PARASITICA. 



In China, Hungary, Spain, and other countries horses frequently 

 suffer from the presence of a threadworm {Filaria ha;morrhagica^ 

 Railliet; F. multipapillosa^ Condamine and Drouilly) in the subcuta- 

 neous connective tissue, causing effusions of blood under the scurf 

 skin and incrustations of dried blood on the surface. The eruptions, 

 which appear mainly on the sides of the trunk, but may cover any 

 part of the body, are rounded elevations about the size of a small pea, 

 containing blood which bursts through the scurf skin and concretes 

 like a reddish scab around the erect, rigid hairs. These swellings 

 appear in groups, which remain out for several days, gradually 

 diminishing in size ; new groups appear after an interval of three or 

 four weeks, the manifestation being confined to three or four months 

 of spring and disappearing in winter. A horse will suffer for several 

 years in succession, and then permanently recover. A fatal issue is 

 not unknown. To find the worm the hair is shaved from the part 

 where the elevations are felt, and as soon as a bleeding point is shown 

 the superficial layer is laid open with the knife, when the parasite 

 will be seen drawing itself back into the parts beneath. The worm is 

 about 2 inches long and like a stout thread, thicker toward the head 

 than toward the tail, and with numerous little conical elevations 

 (papillae) around the head. The young worms are numerous in the 

 body of the adult female worm. The worm has become common in 

 given localities, and probably enters the system with food or water. 



Treatment is not satisfactory, but the affected surface should be 

 kept clean by sponging, and the pressure of harness on any affected 

 part must be avoided. Thus rest may become essential. The part 

 may be frequently washed with a strong solution of sulphide of 

 potassium. 



SUMMER SORES FROM FILARIA IRRITANS. 



The summer sores of horses {Dermatitis granulosa, boils) have 

 l)een traced to the presence in the skin of another parasite, 3 milli- 

 meters in length and extremely attenuated {Filaria irritans Railliet). 

 The sores may be seen as small as a millet seed, but more frequently 

 the size of a pea, and may become an inch in diameter. They may 

 nppear on any point, but are especially obnoxious where the harness 

 jiresses or on the lower parts of the limbs. They cause intense and 

 insupportable itching, and the victim rubs and bites the part until 

 extensive raw surfaces are produced. Aside from such friction the 

 sore is covered b}'- a brownish-red, soft, pulpy material with cracks 

 or furrows filled with serous pus. In the midst of the softened mass 

 are small, firm, rounded granulations, fibrinous, and even caseated, 

 and when the soft pultaceous material has been scraj^ed off, the sur- 

 face bears a resemblance to the fine yellow points of miliary tubercu- 



