Groff Tierra C, Lorenz Teresa J, Crespo Rocio, Iezhova Tatjana, Valkiūnas Gediminas, Sehgal Ravinder N M
San Francisco State University, Biology Department, 1600 Holloway Ave, San Francisco, CA, 94312, USA.
U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station, 3625 93rd Ave SW, Olympia, WA, 98512, USA.
Int J Parasitol Parasites Wildl. 2019 Jul 19;10:93-100. doi: 10.1016/j.ijppaw.2019.07.007. eCollection 2019 Dec.
A juvenile White-headed woodpecker () fitted with a radio tag was located dead at approximately 22-days post-fledging in Yakima county in central Washington in July 2015. Postmortem examination revealed an enlarged liver and spleen plus evidence of iron sequestration. Microscopic examination observed young gametocytes within the cytoplasm of erythrocytes, and exo-erythrocytic meronts within the cytoplasm of capillary endothelial cells, hepatocytes, and myocytes, and free in the tissues. These attributes implicated a haemosporidian infection that likely resulted in mortality. Subsequent sampling results of local woodpecker species in the same area during the breeding season in June-July 2016 and May-July 2017 showed other individuals infected with parasites. Nested Polymerase Chain Reaction (PCR), sequencing, and microscopic analyses for avian haemosporidians revealed infections with (Haemosporida, Haemoproteidae). This parasite was characterized molecularly and morphologically. This is the first report of a haemosporidian infection in a White-headed woodpecker anywhere in its range, and the first reported suspected mortality from haemoproteosis for a woodpecker (Piciformes, Picidae). The use of radio-tagged birds is an asset in wildlife haemosporidian studies because the effect of the pathogen can be monitored in real time. Additionally, this methodology provides opportunities to collect fresh material for microscopic and histological examination from wild birds that have died from natural causes.
2015年7月，一只佩戴无线电追踪器的未成年白头啄木鸟在华盛顿州中部亚基马县离巢约22天后被发现死亡。尸检显示肝脏和脾脏肿大，并有铁螯合迹象。显微镜检查发现红细胞胞质内有年轻配子体，毛细血管内皮细胞、肝细胞和肌细胞的胞质内有红细胞外裂殖体，且在组织中呈游离状态。这些特征表明存在血孢子虫感染，可能导致了死亡。随后在2016年6 - 7月和2017年5 - 7月繁殖季节对同一地区当地啄木鸟物种的采样结果显示，其他个体也感染了寄生虫。对鸟类血孢子虫进行巢式聚合酶链反应（PCR）、测序和显微镜分析，发现感染了（血孢子虫目，血变科）。对这种寄生虫进行了分子和形态学特征分析。这是白头啄木鸟在其分布范围内任何地方首次出现血孢子虫感染的报告，也是首次报告啄木鸟（雀形目，啄木鸟科）疑似因血变虫病死亡。在野生动物血孢子虫研究中，使用无线电追踪鸟类是一项优势，因为可以实时监测病原体的影响。此外，这种方法为从自然死亡的野生鸟类中收集用于显微镜和组织学检查的新鲜材料提供了机会。
