294 PRINCIPLES OF VETERINABT SUBGEEY 



■while the swelling may persist for several days. The con- 

 tents of the blisters are absorbed and the blister, unless opened, 

 dries up in a few days. A new horny layer is formed and the 

 old one thrown off. In those cases where the blister is 

 opened, nine to fourteen days pass before a new epidermis is 

 reproduced. 



3. Third degree : An excessive temperature acted for 

 some time. Here carbonization of the tissues occurs. Under 

 pus formation the necrotic tissues are loosened and thrown 

 off, after which granulations spring up and finally a scar 

 leading to more or less deformity forms. 



What points are to be considered in the prognosis of a hv/rn ? 

 Primarily the extent and next the intensity of the burn. 



How much of the body surface must be bv/rned to entitle to a 

 doubtful or unfavorable prognosis ? 

 It seems that in the horse when one-fifth to one-tfenth of 

 the body surface is destroyed, a fatal termination is imminent. 



What constitutional symptoms do extensive burns produce ? 



Dogs are very much excited ; later distinct collapse with 

 dyspnoea and subnormal temperature follows ; in other 

 instances, there are convulsions. In horses, after extensive 

 burns, especially when the mucous membrane of the respira- 

 tory tract is injured by the inhalation of hot and acrid vapors, 

 a fatal hemoglobinuria finishes the creature. 



How is the appearance of hemoglobinwria after extensive 

 burns explained ? 

 As a result of the action of the heat upon the skin capil- 

 laries, the blood disintegrates and hemoglobinuria is created 

 at once. The hemoglobin which now circulates in the blood 

 current causes hemoglobinuria. 



