Symi^toms. Course. 189 



. SiisceptilDility. Marasmus and anemia predispose to the 

 disease, and deficient cleanliness and moist air of the barn indi- 

 rectly act in the same manner. 



Symptoms. The disease begins with reddening and mod- 

 erate swelling of the mncosa of the month, and after one or two 

 days pecnliar membranous deposits are formed on the mucosa. 

 Very fine, whitish points appear on different places of the buccal 

 cavity, particularly on the back of the tongue, on its margins, 

 near the lip, on the gums around the teeth, and behind the an- 

 gles of the mouth, which enlarge to the size of a lentil and keep 

 on growing, becoming thicker and assuming a gray, later a yel- 

 lowish color ; they are surrounded by an intensely reddened halo. 

 It is difficult to remove the pseudomembranes ; if it is done, an 

 intensely red, easily bleeding surface appears; the detached 

 membrane is quite friable and looks like tenacious pus or soft 

 cheese. At the margins of the lips small vesicles and later yel- 

 lowish-brownish crusts are formed, which bleed easily on being 

 touched. (According to Ziirn, the pseudomembranes are only 

 formed after rupture of the vesicles.) 



In cases with a favorable termination the pseudomembranes 

 become detached, beginning at the margins, and leave behind 

 intensely red, easily bleeding erosions. These soon become 

 closed by a newly-formed epithelial covering. In serious cases, 

 the number of pseudomemlu-anous spots increase, and those al- 

 ready formed grow and become confluent. This leads to the 

 formation of continuous thick yellowish-brown pseudomem- 

 branes which cover the ulcerated mucosa extensively. Bluish- 

 red elevations are also formed, particularly on the gums, which 

 easily bleed. The ulcerative process may extend into the al- 

 veoli and lead to loosening of the teeth. 



In consequence of the painful condition of the mucosa of 

 the mouth sucking or the taking of food becomes greatly dis- 

 turbed and finally impossible. There is profuse salivation, and 

 in severe cases a repulsive foetor ex ore. The tissues around 

 the mouth become dark in consequence of adhering dust and 

 dirt. The sick animals become rapidly emaciated, there may be 

 constipation or diarrhea and colicky pains; a catarrhal pneu- 

 monia sometimes sets in, and finally the exhausted animals die. 



Course. In lambs less than two weeks old, the disease gen- 

 erall}^ takes a very rapid and often fatal course. In older ani- 

 mals, the course is generally more favorable, but fatal cases 

 occur, especially in consequence of complications. The mortal- 

 ity ranges from 8-15-20% in different epizootics; occasionally 

 all of the affected lambs will die (Koenig). The disease also 

 causes losses in consequence of the fact that it disturbs the de- 

 velopment of the animals, even if they do not die from it, and it 

 is very difficult to eradicate it from a herd after it has once made 

 its appearance. 



