INFECTIOUS DISEASES. 571 



and most constant lesion is probably the petechias, so often observed 

 in the muscle or on the serous membranes of the heart. The heart 

 is generally enlarged and may be the only organ to show evidence of 

 dipease. In other cases the lungs may be studded with petechiae, with 

 a serous exudate present in the thoracic cavity. In addition to the 

 petechiae already noted, the pericardial sac generally contains an 

 increased quantity of fluid. The abdominal cavity may show peri- 

 tonitis and a hemorrhagic condition of the intestines, which probably 

 result from overfeeding in consequence of the ravenous appetite. 

 The liver, although usually normal, sometimes presents a few areas 

 of degeneration. The spleen is at times found to be enlarged and 

 covered with petechise. The kidneys may appear normal or anemic 

 and flaccid, but microscopically they usually show a chronic paren- 

 chymatous degeneration. The lymph glands may be enlarged and 

 hemorrhagic. 



Diagnosis. — ^The diagnosis of the disease is not difficult; especially 

 in advanced stages. The insidious onset, remittent fever, progressive 

 emaciation and anemia, unimpaired or ravenous appetite, staggering 

 gait and polyuria are a train of symptoms which make the disease 

 sufficiently characteristic to differentiate it from other diseases af- 

 fecting horses in this country. The peculiar relapsing type of fever, 

 the great reduction in the number of red blood cells, and the absence 

 of eosinophila are sufficient to differentiate it from the anemias pro- 

 duced by internal parasites, while it may be readily distinguished 

 from surra by the nonsusceptibility of cattle and by the great ease 

 with which the trypanosoma may be found in the latter affection. 



Prognosis. — The prognosis of the disease is very unfavorable. 

 Veterinarians in different sections of the country where it is preva- 

 lent report a mortality of 75 per cent or even higher. Recovery 

 takes place only when treatment is begun early or when the animal 

 has a long convalescent period. 



Treatment. — The treatment of the disease has so far been far from 

 satisfactory. The iodid, permanganate, and carbonate of potash 

 have been used. Arsenic, axytol, quinin, and silver preparations 

 have been suggested, but all have been uniformly without success. 

 Intestinal antiseptics have been resorted to, and the results are 

 encouraging but not altogether satisfactory. Symptomatic treat- 

 ment seems to be the most dependable. For instance, Davison, of 

 this bureau, was able to reduce greatly the mortality from this 

 affection by giving an antipyretic of 40 grains of quinin, 2 drams 

 of acetanilid, and 30 grains of powdered nux vomica four times 

 daily. In the late stages, with weak heart action, alcohol should 

 be substituted for acetanilid. Cold-water sponge baths may be given, 

 and in addition frequent copious injections of cold water per rectum, 

 which has a beneficial effect in reducing the temperature and in 



