THE BLOOD, 235 



this disease the relative proportion of red corpuscles is less 

 than normal. 



The normal color of blood serum is a light golden 

 yellow (straw color). After the destruction or breaking down 

 of a large number of red corpuscles their coloring matter is 

 dissolved in the plasma of the blood and is partially converted 

 into methemoglobin. This causes a reddening of the serum 

 (Hemoglobinemia). The presence of the coloring matter of 

 the muscles may produce a similar result. 



Diseases of the Blood. 



Essential (idiopathic) anemia. Bloodlessness. Consists in a 

 diminishment of the quantity of blood without a determinable' 

 cause. Blood pale and coagulates poorly. Mucous membranes 

 pale and low temperature. Pulse small, heart tones metallic 

 sound. Appetite poor. Tendency to dropsical swellings. General 

 weakness. Mostly in young animals. 



Pernicious anemia. Primary anemia of adult animals with 

 fatal termmation. Fever not constant. Mucous membranes pale 

 and somewhat yellowish. Pulse gradually becoming more rapid, 

 appetite less and less. Increased weakness terminating in death 

 Blood watery, changes in red corpuscles characteristic: usually 

 large ones with nuclei, and small irregular forms, seem elongated 

 angular or toothed, club or pear shaped. 



Leucemia. Chronic alterations of the blood and increase in 

 number of white corpuscles. Animals are languid, lazy, sweat 

 easny, pale mucous membranes. Appetite grows less, pulse in- 

 creases, small. Heart tones, metallic sound. Enlargement of lym- 

 phatic glands usually present. Sometimes ecchymotic hemor- 

 rhages in the mucous membranes. 



Hemoglobinuria of cattle. An acute non-contagious infec- 

 tious disease of cattle caused by the presence of the protozoon 

 Pyroplasma bigeminum m the blood, and characterized by hemo- 

 globinuria. About 12 days after the animals have been on an in- 

 fected pasture, the first symptoms appear— fever, loss of appetite 

 diarrhea. Urine light to dark red, very foamy, urination painfuL 

 Urine contains hemoglobin and coagulates into a gelatinous mass 

 vvhen boiled. Gait stifif and clumsy, often attended with pain 

 Also anemia, icterus, general debility, continuous lying down 

 edematous swelling of head and neck. 



The cause of the disease is found in the blood in the form of 

 a protozoon called Pyroplasma bigeminum. The latter has a 

 roundish form which may become very irregular as a result of 

 ameboid movement. 



When fully developed they are found in the red corpuscles in 

 the form of two pear shaped bodies with the narrow ends ap- 



