SURRA. 557 



The temperature has fallen and, in some cases, has attained normal 

 or even subnormal limits. The visible mucous membranes are clean, 

 and the conjunctival petechias begin to fade; the pulse, however, will 

 be found to be weak and thready in character, but the appetite excel- 

 lent, and, in fact, if it were not for the loss of flesh and slight edema 

 of the legs, there would be little to show that the animal was sick. 

 But unfortunately this condition does not continue for any length of 

 time, for again the temperature is elevated ; in the course of a few 

 hours the thermometer registers a still higher degree, the animal is 

 dull and dejected, and by the following day the visible mucous mem- 

 branes present a yellow tinge ; large ecchymoses, dark in color, appear 

 on the conjunctival membranes, the action of the heart is irritable, the 

 pulse full and quick, or at times intermittent, and regurgitation may 

 be observed in the jugulars, the breathing is quickened, and the indi- 

 vidual respirations are shallow. On watching an animal in this con- 

 dition it may be noticed that it takes 7 to 8 very short inspirations, 

 and these are followed by a much more prolonged and sonorous one ; 

 at the same time the breathing is more abdominal than thoracic in 

 character. On examination of the legs it will be found that the swell- 

 ing and edema have increased considerably, and that on the under 

 surface of the abdomen, where it was previously confined to the 

 sheath, it has now commenced to spread forward along the subcutane- 

 ous tissue between the skin and the muscles. During the whole of this 

 time the appetite will have varied little, and the evacuations will be 

 only slightly, if at all, altered' in character. In the blood a repetition 

 of the previous events takes place, the parasites make their appear- 

 ance and increase to a maximum and again suddenly or gradually 

 disappear, according to the length of the fever period. These periods, 

 alternating with and without fever, may go on for a considerable 

 time. The progress of the disease is variable and greatly depends 

 upon the condition of the animal attacked, the weak one succumbing 

 very rapidly, but each return of the fever brings with it, as a rule, an 

 increase in the severity of the symptoms. There is increased yellow- 

 ness of the membranes, fresh crops of petechia? on the conjunctiva, a 

 collection of gelatinous material at the inner angle, which at times 

 becomes red in color from an admixture of blood, and which on 

 microscopic examination is found to contain a varying number of the 

 surra parasites; increased swelling and edema of the extremities and 

 abdomen, which now extends between the fore limbs and up the 

 chest. During this time the w r asting has been steadily progressive, 

 especially of the muscles of the back and those surrounding the hip 

 joint and the glutei. 



Toward the termination of the disease it will be noticed that an 

 animal is disinclined to move, and when made to do so there will be 

 manifest loss of power over the hind quarters, somewhat simulating 



