Pathological findings in the mass mortality event of saiga antelope, May 2015

Field-pathological findings of 33 saiga antelope carcasses (adults and new-born) found in two sites (Tengiz and Turgai, Kazakhstan) during a mass die-off event in May 2015. In Kazakhstan May 2015, approximately 200,000 saiga antelopes died within a month-period causing a loss of two-thirds of the global population. The dramatic event occurred during calving season when females and young males stop migrating and form massive aggregations for calving purposes. With 100% morbidity and 100% mortality of affected herds observed, the 2015 die-off left the largest saiga population, Betpak-Dala, with approximately 30,000 survivors based on post mortality census, highlighting the imminent extinction threats to this critically endangered species. The lack of pathological investigations during historical mass mortality events has limited our understanding of disease-related mortalities in saiga antelope. Generally, aetiological agents were isolated from dead saiga, but the disease course and a full necropsy were not performed nor present in the records. However, for the first time, a full pathology report was possible during 2015.

2015年5月，在哈萨克斯坦的腾格里和图尔加伊两地，发现了33具死亡野生赛加羚羊尸体（包括成体和新生个体），这些尸体是在一次大规模死亡事件中被发现的。在2015年哈萨克斯坦，约20万头赛加羚羊在一个月内死亡，导致全球赛加羚羊种群减少了三分之二。这一悲剧性事件发生在产羔季节，此时雌性和年轻雄性停止迁徙，为了产羔而形成大规模聚集。观察到的受影响群体中，发病率与死亡率均达到100%，2015年的死亡事件使得最大的赛加羚羊种群——贝帕克-达拉种群，根据死后的普查，幸存者数量约为3万头，凸显了这一濒危物种面临灭绝的紧迫威胁。历史上在大量死亡事件中缺乏病理学调查，限制了我们对赛加羚羊疾病相关死亡的认识。通常，病原体是从死去的赛加羚羊中分离出来的，但疾病的进程和完整的尸检并未进行，且在记录中并未提及。然而，在2015年，首次得以完成一份完整的病理学报告。