Haerer G, Nicolet J, Bacciarini L, Gottstein B, Giacometti M
Institut für Tierpathologie, Universität Bern.
Schweiz Arch Tierheilkd. 2001 Apr;143(4):193-201.
To elucidate the importance of different causes of mortality which could explain the downward trend of the hare populations in Switzerland and for monitoring selected zoonoses, the health and reproductive status of 167 perished brown hares (Lepus europaeus) was assessed. Concerning causes of mortality, traumas were by far the most frequent diagnosis, 80% of the hares dying because of injuries. Animals killed by road traffic were highly represented. Predators (such as dogs, domestic cats, lynx, martens, buzzards, and golden eagles) killed 16% of the analysed animals. In juveniles, predation was significantly more frequent than in adults. Infectious diseases led to death in 15% of the animals, and cases of pasteurellosis, brucellosis, pseudotuberculosis, tularaemia, listeriosis, and toxoplasmosis were diagnosed. In 5% of the hares, the cause of death pertained to other categories or remained unclear. Reproductive performance was judged to be normal, since mean litter size was 2.5 per female and pregnancy rate in March-June was 74%. We conclude that neither a specific infectious disease, for which adult hares are particularly susceptible, nor an insufficient reproductive performance are responsible for the decline of brown hare populations in Switzerland. This phenomenon is rather a cause of a reduced survival rate in leverets.
为了阐明可能解释瑞士野兔种群数量下降趋势的不同死亡原因的重要性，并监测选定的人畜共患病，对167只死亡的褐兔（欧洲野兔）的健康和繁殖状况进行了评估。关于死亡原因，外伤是迄今为止最常见的诊断结果，80%的野兔死于受伤。被道路交通撞死的动物占比很高。捕食者（如狗、家猫、猞猁、貂、秃鹫和金雕）杀死了16%的被分析动物。在幼兔中，被捕食的情况明显比成年兔更频繁。传染病导致15%的动物死亡，并诊断出巴氏杆菌病、布鲁氏菌病、假结核病、兔热病、李斯特菌病和弓形虫病病例。在5%的野兔中，死亡原因属于其他类别或仍不清楚。繁殖性能被判定为正常，因为平均每只雌兔产仔数为2.5只，3月至6月的怀孕率为74%。我们得出结论，瑞士褐兔种群数量下降既不是因为成年野兔特别易患的某种特定传染病，也不是因为繁殖性能不足。这种现象相当于是幼兔存活率降低的一个原因。
