52 DISEASES OF POULTRY. 



monary blood-vessels is a disease which quite fre- 

 quently affects birds that are molting, and also young- 

 chickens, ducks, goslings, pheasants, and cage birds. 

 The distention of the blood-vessels which are very 

 abundant in the lungs, causes pressure upon the finer 

 bronchi and air cells and may lead to death from as 

 phyxia. Or there may be rupture of the vessels and 

 the escape of blood, which blocks up the bronchi and 

 alveoli and collects in the air sacs. In either case death 

 soon results. 



Causation. — This disease is generally caused by 

 exposure to cold and the chilling of the surface of the 

 body, which leads to contraction of the external blood- 

 vessels and forces an undue amount of blood into the 

 internal organs. It is seen in fowls that are molting 

 and which are exposed to cold draughts or rain while 

 the skin is over -sensitive and partially denuded. It 

 also occurs in young birds which, for any reason, are 

 not kept sufficiently warm. It is common among 

 young chickens and turkeys allowed to run out in the 

 rains of early Spring, and among incubator chicks that 

 are allowed to get chilled. 



Congestion of the lungs may also occur in full-fed, 

 plethoric birds from over -abundance and too great 

 richness of the blood. This liquid then becomes thick 

 and circulates with more difficulty than when in a 

 normal condition; the delicate vessels in the lungs be- 

 come clogged, distended and finally ruptured. This 

 form of the disease is the result of improper feeding 

 and lack of exercise and is seen most frequently in 

 cage birds. 



Symptoms. — The affected bird breathes rapidly and 

 with difficulty. It is indisposed to move, stupid, sleepy, 

 and does not notice what is going on about it. Thick 



