CONTAGIOUS DISEASES OF DOMESTICATED ANIMALS. 55 



fibrous coagula ami a black, viscid, semi-fluid blood ; in the left side of the heart, 

 which is often empty, there is nothing found but fibrinous concretions. The mucous 

 membrane of the small intestine is pale, yellowish, infiltrated, and softened^ some- 

 times covered with red stri;e or black points. These black points are compounds of 

 fat and pigment (T. O. Heusinger). The mucous membrane of the large intestine 

 shows hypera'mia, which is far from being constant. The proventriculus of the gal- 

 linaceans has a gray or a wine-red appearance ; its mucous membrane is ulcerated or 

 covered with granulations; the gizzard is black, (Millet). Do not the granulations 

 depend upon the ulceratiou of the pepsine glands? The cerebral envelopes, princi- 

 pally at the base, are congested, engorged with a black blood resembling that found 

 in the veins; a section of the brain shows sometimes a very apparent ])unctation ; iu 

 other cases, much more common, it is ana-mic. Analagous changes are met with in 

 the spinal cord. 



The local disorders of gangrenous ergotism are those of dry gangrene (see (?aH- 

 greue). 



Physiological action. — The symptoms of gangrenous or convulsive ergotism, as a 

 whole, indicate incontestably that the nervous system fills the principal role. The 

 phenomena observed by Hoppe when he placed ergotiue in contact with the isolated 

 organs of the frog or the rabbit would remove all doubt if any could exist. Ergotine 

 causes a marked stimulation of the heart, followed by a weakening and a retardation 

 of its movements; the intestine contracts, but the contraction is not renewed after a 

 second application; the blood vessels dilate; soon follows a contraction with conges- 

 tion of the rasa vasorum which swell and cause the walls of the veins and arteries to 

 become rigid ; the sensitive nerves are partially paralyzed ; later their sensibility is 

 increased; a general intoxication congests the brain and spinal cord. This last eflfect 

 is not constant ; the autopsies show that though the envelojies of the cerebro-spinal 

 axis are always congested, wholly or iu part, the nervous centers themselves are quite 

 ©ften auii-mic. , . 



It follows from these results which are conformable to what is observed in ergotism 

 that the primitive phenomena depend upon a sedation of the sensory nervous system, 

 and this ana'sthesia issucceeded by a hypera>sthesia and a retardation of the circula- 

 tion. The exaltation of the sensibility has not always the same seat ; this circum- 

 stance explains the variations of the symptoms and the predominant lesions of a func- 

 tional apparatus. In all cases the hypenesthesia excites reflex action, sometimes in 

 the intestinal tube (colic, vomiting, and diarrhea); at other times in the voluntary 

 muscles (contractions and convul,>-ions) ; at still other times in the involuntary mus- 

 cles of the vessels (gangrene). These reflex actions may be successive, simultaneous, 

 ■or they are developed separately and remain separated during the whoh^ course of the 

 disease. With man, who can give an account of his subjective sensations, intense 

 pain precedes the contraction ; then follows, according to the intensity of the disease, 

 convulsions varying from trembling to epileptic attacks. The overstimulation leads 

 to exhaustion, which brings a calm in the sensitive system. Intolerable pains, which 

 are more localized, also precede thci dry gangrene ; the patient feels in the pait which 

 becomes the seat of it a cold sensation ; later, this is recognized by the thermometer 

 and to the patient it seems glacial ; the sensation islosi when the gangrenous eftect is 

 accomplished. The dilatation of the vessels, followed by a narrowing of their channels 

 are phenomena which are connected with primitive ana'sthesia, a secondary hyper- 

 icthesia, and with reflex action, which aifect the vaao-motor nerves. The rigidity and 

 congestion of the vascular tubes, the weakening of the contraction of the heart, re- 

 lard the circulation in the extremities, favor the stagnation of the blood, and conse- 

 quently necrosis, even if the reflex phenomena are not sufliciently intense to obliter- 

 ate the channel of the art'erent vessel and pioduce mortification by ana-mia. What 

 is produced iu an intense manner at one or several extremities is rei)eat('(l at all the 

 perii)hery in gangrenous and convulsive ergotism; the lowering of the temperature 

 lias no other cause than the retardation of the circulation and the reflex musctilar 



