Hueffer Karsten, Holcomb Darce, Ballweber Lora R, Gende Scott M, Blundell Gail, O'Hara Todd M
Institute of Arctic Biology, Department of Biology and Wildlife, University of Alaska Fairbanks, 902 North Koyukuk Dr., Irving1 #311, Fairbanks, Alaska 99775, USA.
J Wildl Dis. 2011 Oct;47(4):984-8. doi: 10.7589/0090-3558-47.4.984.
The harbor seal population in Glacier Bay National Park, Alaska, has declined by over 70% since 1992. The reasons for this decline are not known. We examined serum antibodies and feces for evidence of exposure to multiple pathogens in this population. We also studied harbor seals from a reference site on Kodiak Island. In 2007, we found antibodies against Leptospira spp. in 31% of specimens from harbor seals in Glacier Bay, but no detectable serum antibodies in samples from Kodiak. In 2008, no samples had detectable antibodies against Leptospira spp. No serum antibodies against Toxoplasma gondii, morbilliviruses, or presence of Cryptosporidium in fecal samples were detected. However, Giardia was found in 6% of the fecal samples from Glacier Bay. Our results indicate that the harbor seal population in Glacier Bay National Park could be immunologically naïve to distemper viruses and therefore vulnerable to these pathogens. Given the relatively low prevalence of antibodies and low titers, pathogens likely are not the reason for the harbor seal decline in Glacier Bay.
自1992年以来，阿拉斯加冰川湾国家公园的斑海豹数量减少了70%以上。数量减少的原因尚不清楚。我们检测了血清抗体和粪便，以寻找该种群接触多种病原体的证据。我们还研究了来自科迪亚克岛一个参考地点的斑海豹。2007年，我们在冰川湾斑海豹31%的样本中发现了抗钩端螺旋体属的抗体，但在科迪亚克岛的样本中未检测到血清抗体。2008年，没有样本检测到抗钩端螺旋体属的抗体。未检测到抗弓形虫、麻疹病毒的血清抗体，粪便样本中也未发现隐孢子虫。然而，在冰川湾6%的粪便样本中发现了贾第虫。我们的结果表明，冰川湾国家公园的斑海豹种群可能对瘟热病毒缺乏免疫力，因此易受这些病原体的侵害。鉴于抗体的患病率相对较低且滴度较低，病原体可能不是冰川湾斑海豹数量减少的原因。
