550 DISEASES OF THE HORSE. 



observed will not easil}^ be forgotten. If the parasite has not been 

 discovered in the blood for some days, the symptoms mentioned above 

 may be the only ones noticed, and, as a rule, when treated with febri- 

 fuges, the horse quickly improves in health and the appetite returns. 

 This condition does not last for more than a few days, wiien the 

 animal is again observed to present a dull and dejected appearance, 

 and on examination well-marked symptoms are found ; the skin is 

 hot, the temperature more or less elevated — 101.7° to 104° F.; the 

 pulse full and frequent — 56 to 64 beats per minute ; the visible mu- 

 cous membranes may appear clean, but the conjunctival membranes, 

 especially those covering the membrana nictitans, are usiuilly the seat 

 of dark-red patches of ecchymosis, varying in size in different an- 

 imals. There is more or less thirst and slight loss of appetite ; the 

 animal eats its grain and green grass, but leaves all or a portion of 

 the hay with w^hich it has been supplied. At the same time there 

 are slight catarrhal symptoms present, including lachrymation and a 

 little mucous discharge from the nostrils. Occasionally at this period 

 of the disease the submaxillary glands may be found enlarged and 

 perhaps somewhat tender on manipulation. One symptom is mark- 

 edly absent, namely, the presence of rigors or the objective sign of 

 chilliness. In addition, it will be noted that there is some sw^elling and 

 edema of the legs, generally between the fetlock and the hock, which 

 pits but is not painful on pressure, and in case of horses there may 

 be i^resent also at this stage of the disease some swelling of the sheath. 

 AATien the fever and concomitant symptoms have declared themselves 

 for a short period, one thing becomes especially noticeable in every 

 animal attacked, namely, the rapidity with which it loses flesh. If 

 the blood has been examined microscoi^ically during the second period 

 of fever, at first a few parasites wall have been observed in it, w^hich 

 day by day increase in number and reach a maximum, where they 

 remain for a varying period, or at once suddenly or gradually disap- 

 pear during the period of apyrexia. After the fever and the accom- 

 panying symptoms have for the second time been present for some 

 days — the period varjang from one to six — the animal is found to 

 have lost the dull, dejected appearance and to look bright. The tem- 

 perature has fallen and, in some cases, has attained normal or even 

 subnormal limits. The visible mucous membranes are clean, and the 

 conjunctival petechia) begin to fade; the pulse, however, will be found 

 to be weak and thready in character, but the appetite excellent, and, 

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

 legs, there w^ould 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 membranes 



