494 



DISEASES OF THE SKIN. 



fungi existing on the surface of the plant, on reaching the unpig-- 

 mented skin, ah-eady affected by solar erythema, further irritate it 

 and produce a more or less intense dermatitis. Under certain cir- 

 cumstances it is possible that insects may determine what has been 

 called buckwheat eruption (buckwheat fields constitute excellent 

 pastures for bees) ; it is also possible that an idiosyncrasy exists — ^ 

 an individual sensitiveness which favors the development of this 

 affection. 



Affected animals. The disease is most frequently observed 

 on white, piebald, or spotted sheep, especially on lambs. It is also 

 found in the pig, more rarely in the goat (Hering) or the ox, and 

 in solipeds, the skin of which is partially discolored. Black or 

 spotted black sheep, those living in stables and those going iu pas- 

 ture only during damp weather or which pasture in the shade, 

 are not subject to it. An eruption may also be produced when 

 the animals are exposed to the sun's rays from eight days to 

 four weeks after having ceased feeding on buckwheat ; as soon 

 as they are subjected again to permanent stabling it disappears, to 

 return again if the influence of the sun is felt anew. Hemminger 

 observed a disease similar to fagopyrism in horses working in 

 potato fields at the time when the stems of the latter were in full 

 growth. 



Symptoms. They consist of an intense redness (erythema) and 

 and inflammatory tumefaction (erythematous dermatitis) of the ears,, 

 eyelids, and face, which extends at times to the guttural region and 

 to the neck and shoulders ; these phenomena are accompanied by 

 an intense pruritus, the animals are restless, shake the head, rub 

 themselves, perform uncontrollable movements ; we may even ob- 

 serve rabiform symptoms. Sometimes the red and tumefied skin 

 becomes covered with vesicles, from the size of a lentil to that of a 

 pea, containing a yellowish liquid ; the small wounds resulting 

 from their rupture become cicatrized and covered with scabs (pimple 

 of the sheep, bullous erysipelas). The intensity of eruption is in 

 proportion to the quantity of buckwheat consumed and the duration 

 of exposure to sunlight. During the winter it is only expressed by 

 itchings and scratching. 



In grave cases we see respiratory troubles (erysipelatous inflam- 

 mation of the respiratory tract), also fever and cerebral symptoms : 

 vertigo, stupefaction, whirling, spasms, intense excitement, etc., 

 which are undoubtedly produced by the propagation of the erysipe- 



