Acute Lymphangitis of Plethora in the Horse. 389 



us we have the overfeeding of an animal having a strong diges- 

 tion, we have an absolute compulsory inactivity, with a suspen- 

 sion to a large extent of the functions of nutrition, sanguifica- 

 tion, secretion, and elimination ; we have in consequence an in- 

 crease of the blood pressure, and of the solids of the blood and 

 of the plasma of the lymph ; we have a suspension of the great 

 motor force of lymph circulation^ namely, the muscular contrac- 

 tion, and we have the consequent tardy movement of the lymph, 

 the great increase of lymphocytes, and the distension and en- 

 gorgement of the lymph glands. As soon as this has reached a 

 certain stage the congestion and incipient inflammation of the 

 gland determines the precipitatioti of fibrine, the obstruction of 

 the gland, and of the entire circulation of lymph in the lower 

 part of the limb. The fever, the local swelling, and the subse- 

 quent steps follow as a matter of course. This view is sustained 

 by the fact that incipient cases can be cured by muscular move- 

 ment alone. The rarity of the disease in the fore limb may be 

 ascribed to the greater force of the vis a tergo, the lesser height 

 of the lymph column, and the stronger action of the aspiratory 

 power of the chest on the lymphatic vessels. 



In addition to the causes mentioned above must be noted the 

 following : The disease is an affection of heavy draft horses, in 

 which the tissues are more lax, and the lymph plexus in the con- 

 nective tissue of the hind limb is much more abundant. It is 

 common in the heavy English, Scotch and Belgian draft horses, 

 and rare in the English racer, the American trotter, and in the 

 average light American horse. The malady is most frequent in 

 spring and autumn, when the work is hardest and the feeding 

 most abundant. It rarely attacks the horse in steady work, but 

 appears after an idle Sunday spent in the stable (Monday morn- 

 ing disease), or after one or more days of compulsory idleness 

 from heavy rains or other cause. The damp climate of western 

 Europe has probably an exciting influence, as it has in producing 

 the lymphatic constitution. In the same line of thought Zundel 

 says that many cold weather attacks would be prevented by clip- 

 ping off the heavy coat which keeps the entire system relaxed. 

 In some cases a sudden change of food, and in others musty oats 

 have been claimed as causes. 



Diagnosis. Lymphangitis is distinguished from a simple drop- 



