CROUPOUS PNEUMONIA IN HORSES 101 



scribed and about the size of an apple. The case was discharged 

 from the hospital on July 10th as recovered. Nos. 20, 21, 24, 25 

 and 27 show the condition of the blood at the height of the leu- 

 cocytosis. No. 29 was a case of strangles with necrotic pneumonia; 

 died Dec. 13th. Note the excessive polycythemia. 



CROUPOUS PNEUMONIA IN HORSES 



Though an anemia is shown in cases of pneumonia the diminu- 

 tion in red corpuscles and Hb is not as a rule shown during the 

 early stages of the disease. Often a considerable polycythemia is 

 evident, due to the concentration of the blood by the fever, by 

 exudation and vasomotor influences. In five fatal cases reported 

 by Meier the polycythemia continued to the time of death and 

 reached 9,760,000-13,400,000 corpuscles; 110-125% Hb. Four of 

 these were necrotic or gangrenous. The other case was a double 

 sided pneumonia. In Meier's non-fatal cases a lesser grade of 

 polycythemia occurred in five cases and was of shorter duration 

 than in the fatal cases. In four cases there was no polycythemia. 

 In all of the non-fatal cases but one an anemia was shown during 

 the latter part of the disease. In most cases the anemia was 

 moderate, to 65 or 70%; in one case, chronic pleuro-pneumonia, 

 the red corpuscles were reduced to 3,600,000 with 50% Hb. 



Leucocytosis appears very early in the course of the disease 

 except in very severe cases in which the leucocytes instead of 

 increasing show a diminution. In such cases the prognosis is bad. 

 In a case reported by Meier there was a stage of leucopenia pre- 

 ceding that of leucocytosis, but in the majority of cases reported 

 there was leucocytosis at the time of the first examination. In 

 man leucocytosis appears very early, at the time of the chill 

 (Klein), preceding the exudation (v. Limbeck). The degree of 

 leucocytosis is usually considerable, 12,000-59,600 in Meier's 

 cases. Leucocytosis does not run parallel with the rise of tem- 

 perature as is shown by the following cases. V. Limbeck pointed 

 out that the extent of exudation has much more influence. The 

 polymorphs are much increased relatively and absolutely. Meier 

 found 75.6-92.5% polymorphs. The lymphocytes are correspond- 

 ingly decreased. The large mononuclears are usually within the 

 normal percentages, but are sometimes both relatively and abso- 



