Laboratory of Biomedical Science, Department of Veterinary Medicine, College of Bioresource Sciences, Nihon University, Fujisawa 252-8510, Japan.
Parasitol Res. 2010 Jan;106(2):543-7. doi: 10.1007/s00436-009-1667-7. Epub 2009 Nov 20.
One of vector-borne avian protozoa, Leucocytozoon lovati, has been found in the Japanese rock ptarmigans (Lagopus mutus japonicus), the endangered bird species distributed in the alpine regions in Japan. Vector arthropod species of L. lovati has also been estimated as Simuliidae black flies distributed in the same habitat of the host bird, however, possible blood meals of the black flies were not identified yet. To reveal host animals of black flies, we estimated the blood resources by using molecular techniques. Black flies were collected at Mt. Chogatake, one of the alpine regions of Japan in which Japanese rock ptarmigans live in June 2005. The analyzed 144 specimens were morphologically identified into five species including Simulium japonicum (n = 87), Prosimulium hirtipes (n = 48), Prosimulium yezoense (n = 3), Twinnia japonensis (n = 3), and Cnephia mutata (n = 3). Individually extracted DNA from the black flies was subjected to polymerase chain reaction (PCR) amplification targeting the partial mitochondrial cytochrome b gene of birds or mammals to identify the blood meals. Of 144 black flies examined, 34 specimens were PCR positive for avian hosts (23.6%). No mammalian-derived bloods were detected from the samples studied through. Sequences amplified from 11 black flies consist of S. japonicum, P. hirtipes, and C. mutata showed high similarity to that of the Japanese rock ptarmigan. Therefore, present results conclusively suggest that these three species of black flies might suck the bloods of Japanese rock ptarmigans and could be the vector for L. lovati infection among this endangered bird species of Japan.
日本高山地区特有的雀形目鸟类——日本石鸡（Lagopus mutus japonicus），是一种濒危物种，其体内发现了一种血液原虫——拉里白细胞虫（Leucocytozoon lovati）。拉里白细胞虫的传播媒介——蚋科黑蝇，在同一栖息地也有分布。然而，黑蝇的潜在吸血源尚未确定。为了揭示黑蝇的吸血源，我们使用分子技术来估算其血液资源。2005 年 6 月，在日本高山地区的驹岳山（Mt. Chogatake）采集了黑蝇。该地区是日本石鸡的栖息地之一。分析了 144 个标本，鉴定出 5 个种，包括日本蚋（Simulium japonicum，n = 87）、毛蚋（Prosimulium hirtipes，n = 48）、虾夷蚋（Prosimulium yezoense，n = 3）、双翅蚊（Twinia japonensis，n = 3）和褐蚋（Cnephia mutata，n = 3）。从黑蝇个体中提取的 DNA 分别进行聚合酶链反应（PCR）扩增，以鉴定鸟类或哺乳动物的部分线粒体细胞色素 b 基因，从而确定其吸血源。在检查的 144 只黑蝇中，有 34 只（23.6%）对鸟类宿主呈 PCR 阳性。研究样本中未检测到哺乳动物来源的血液。从 11 只黑蝇扩增出的序列包括日本蚋、毛蚋和褐蚋，与日本石鸡的相似度很高。因此，目前的结果明确表明，这三种黑蝇可能吸食日本石鸡的血液，并且可能是日本濒危鸟类拉里白细胞虫感染的媒介。
