Palmer K M, Stanton N L, Ben-David M, Mionczynski J, Williams S E
Department of Zoology and Physiology, 3166, 1000 East University Ave., University of Wyoming, Laramie, Wyoming 82071, USA.
J Wildl Dis. 2007 Jul;43(3):475-84. doi: 10.7589/0090-3558-43.3.475.
Regional extirpations of pikas (Ochatona princeps) within the last few decades have been attributed to global warming. Other recent global alterations such as increased nitrogen (N) deposition and associated selenium (Se) deficiency may further stress pika populations. In 2003 and 2004, we live-trapped pikas from three populations in Wyoming and measured Se values in their hair. We also sampled hair and liver from museum specimens collected throughout the Northern Rocky Mountains in 1987 and 1988. Our results suggest that liver and hair values were related, and that pika hair reflected the Se concentrations of the geologic parent materials. We determined that animals residing in several remote areas in the Rocky Mountain region could be Se deficient and that increase in N deposition correlated with an increase rather than a decrease in Se values in pika hair. In addition, we found no relation between Se contents in hair and body condition index, suggesting that low Se levels may not have negative effects on individual pikas. Whether Se levels influence reproductive success of pikas is unknown and should be the focus of future studies.
在过去几十年里，北美鼠兔（Ochatona princeps）的区域性灭绝被归因于全球变暖。近期的其他全球变化，如氮（N）沉降增加和与之相关的硒（Se）缺乏，可能会给北美鼠兔种群带来更大压力。在2003年和2004年，我们从怀俄明州的三个种群中活捉了北美鼠兔，并测量了它们毛发中的硒含量。我们还从1987年和1988年在落基山脉北部采集的博物馆标本中采集了毛发和肝脏样本。我们的结果表明，肝脏和毛发中的硒含量相关，并且北美鼠兔的毛发反映了地质母质中的硒浓度。我们确定，生活在落基山脉地区几个偏远地区的动物可能存在硒缺乏，并且氮沉降的增加与北美鼠兔毛发中硒含量的增加而非减少相关。此外，我们发现毛发中的硒含量与身体状况指数之间没有关系，这表明低硒水平可能不会对个体北美鼠兔产生负面影响。硒水平是否会影响北美鼠兔的繁殖成功率尚不清楚，这应该是未来研究的重点。
