ARTERIOSCLEROSIS IN BIRDS 



S. SCHEIDEGGER 

 Institute of Pathology, University of Basle 



Arteriosclerosis ranks first among diseases affecting the 

 arteries, and it is of much more importance in human beings 

 than in animals. All experiments designed to produce such a 

 form of degeneration in the vessels of animals are doubtful, 

 since a severe form of this disease can only be found in man. 

 In animals we never find such severe forms as regards the 

 spreading of the disease or transformation of the tissue, and it_ 

 can never be described as a disease producing clinical symp- 

 toms. In other words, whereas arteriosclerosis is one of the 

 principal diseases in man and a frequent cause of death, in 

 animals it is only of secondary significance, showing only 

 slight malformations, possibly with transformation of the^ 

 vessel wall. The term arteriosclerosis, which etymologically 

 means a hardening of the vessels, in fact stands for a combina- 

 tion of different lesions. At the onset of the disease, we only 

 find some inclusions in the wall. In the final stage there is 

 accumulation of degenerations, malformations, and trans- 

 formations ; all layers of the vessel walls are now affected and 

 we can see calcifications, ossifications, and often an occlusion 

 of the lumen. In other cases the same calcification and ossi- 

 fication process can produce an enlargement of the vessel. At 

 the beginning of the illness we can see a series of various re- 

 actions of unknown and doubtful origin. Some fox^ms of 

 arteriosclerosis constitute pure inflammations, whereas some 

 can be classified as pure degenerations. In some cases this 

 disease of the vessels is restricted to a single organ or to a 

 specific system, i.e. it may be found only in the vessels of the 

 heart, or the vessels of the brain, or perhaps the finer vessels 



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