In human medicine, “sudden death” has been defined by the World Health Organization (WHO) as a non‐violent, unexpected death occurring less than 24 h from the onset of symptoms. The aims of this study were: (1) to estimate the proportional mortality ratio for “sudden and unexpected death” (SUD) in young dogs; (2) to investigate the pathological and microbiological findings in SUD cases in young dogs. For these purposes, a retrospective study of a total of 145 cases of young dead dogs was performed. For each case, we collected information about the age, medical history and the gross and microbiological findings of the animals. The results of this study found 21 cases of SUD. The most frequently observed clinical symptoms in the cases of sudden death were acute respiratory symptoms, followed by acute gastroenteric symptoms, non‐specific symptoms and neurological symptoms. The evaluation of necropsy reports allowed us to observe enteritis in 18 out of 21 cases and pneumonia in seven out of 21 cases. Viral infection with Canine parvovirus type 2 was the most common cause of SUD observed. These results could provide a valuable tool for the investigation of sudden death in young dogs.

中文翻译：

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幼犬突然死亡和意外死亡的病理，细菌学和病毒学发现。

在人类医学中，“突然死亡”被世界卫生组织（WHO）定义为在症状发作后不到24小时内发生的非暴力，意外死亡。这项研究的目的是：（1）估算幼犬“突然和意外死亡”（SUD）的比例死亡率；（2）调查幼犬SUD病例的病理和微生物学发现。为了这些目的，对总共145例年轻的死狗进行了回顾性研究。对于每种情况，我们收集了有关动物的年龄，病史以及肉眼和微生物学发现的信息。这项研究的结果发现了21例SUD。在猝死病例中，最常见的临床症状是急性呼吸道症状，其次是急性胃肠道症状，非特定症状和神经系统症状。尸检报告的评估使我们能够观察到21例中的18例肠炎和21例中的7例肺炎。病毒感染2型犬细小病毒是观察到的SUD的最常见原因。这些结果可为调查幼犬猝死提供有价值的工具。