Fire-associated bear mortalities - Histopathological study

Abstract

In the study, it was aimed to describe the histopathological findings in bears that died as a result of smoke poisoning in natural fire deaths, unlike model studies. Himalayan (n:3) and brown bears (n:7) that died due to smoke in the fire were brought for necropsy. Macroscopically, there were no burns or injuries on the bearskins. The lumens of the trachea were filled with edema and had petechial to ecchymotic hemorrhages. There were hemorrhage areas ranging from the size of a pinhead to large areas of ecchymosis, spreading diffusely in all lung lobes. Pulmonary emphysemas were found in varying sizes, especially in the distal lobes. In all bronchi, bronchioles, most alveoli, and under the pleura were detected-filled areas with erythrocytes. The interalveolar septal regions were noted to be thickened by erythrocyte/inflammatory cell infiltration. Desquamation of lamina epithelialis, edema, emphysema, and carbon pigment in alveolar macrophages and/or free were observed. Since many studies on smoke inhalation are experimental, in this respect, the death findings noted in this study are thought to be very valuable since the bears died naturally. Additionally, symptoms caused by acute smoke inhalation in bears have been described. To the authors' knowledge, this is the first fire-related study in bears, and it is considered that bears have died from carbon monoxide inhalation.

Keywords

• bear
• fire
• histopathology
• mortality
• smoke inhalation

Ethical Statement

Since no live animals were used in this study, ethical permission was not required.

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