Outbreaks of bacterial cold-water disease (BCWD), caused by Flavobacterium psychrophilum, are widespread in Japan, especially among ayu Plecoglossus altivelis. There are few investigations of F. psychrophilum in river water, and its seasonal distribution has not been clarified. We aimed to identify the spatiotemporal dynamics of F. psychrophilum and ayu to provide information that is useful for establishing a countermeasure for BCWD. Quantitative analysis of environmental DNA (eDNA) was used to clarify the year-round dynamics of ayu and F. psychrophilum. We sampled river water from the Nagara and Ibi rivers in Japan, and conducted monthly water sampling and eDNA quantification. Changes in the eDNA concentration of ayu were consistent with the known life histories of the fish. There was a strong negative correlation between the eDNA concentration of F. psychrophilum and water temperature, suggesting a strong dependence of F. psychrophilum dynamics in the river on water temperature. Furthermore, relatively high eDNA concentrations were recorded for both organisms in early summer and fall, suggesting that ayu is infected with F. psychrophilum during these seasons when experiencing up- and downmigration, respectively.
相似文献 |
|||||||
|
|||||||
|
排序方式： 共有92条查询结果，搜索用时 31 毫秒
31.
32.
Yoshihiro KOBAYASHI Tetsushi HIRANO Takuya OMOTEHARA Rie HASHIMOTO Yuria UMEMURA Hideto YUASA Natsumi MASUDA Naoto KUBOTA Kiichi MINAMI Shogo YANAI Mitsuko ISHIHARA-SUGANO Youhei MANTANI Toshifumi YOKOYAMA Hiroshi KITAGAWA Nobuhiko HOSHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1355-1361
33.
Nagao K Okazaki R Nakamura T Miura YN Osawa T Bajo K Matsuda S Ebihara M Ireland TR Kitajima F Naraoka H Noguchi T Tsuchiyama A Yurimoto H Zolensky ME Uesugi M Shirai K Abe M Yada T Ishibashi Y Fujimura A Mukai T Ueno M Okada T Yoshikawa M Kawaguchi J 《Science (New York, N.Y.)》2011,333(6046):1128-1131
Noble gas isotopes were measured in three rocky grains from asteroid Itokawa to elucidate a history of irradiation from cosmic rays and solar wind on its surface. Large amounts of solar helium (He), neon (Ne), and argon (Ar) trapped in various depths in the grains were observed, which can be explained by multiple implantations of solar wind particles into the grains, combined with preferential He loss caused by frictional wear of space-weathered rims on the grains. Short residence time of less than 8 million years was implied for the grains by an estimate on cosmic-ray-produced (21)Ne. Our results suggest that Itokawa is continuously losing its surface materials into space at a rate of tens of centimeters per million years. The lifetime of Itokawa should be much shorter than the age of our solar system. 相似文献
34.
35.
36.
Aiko Nakano Hidetoshi Ikeno Toshifumi Kimura Hiromichi Sakamoto Masako Dannoura Yasuhiro Hirano Naoki Makita Leena Finér Mizue Ohashi 《植物养料与土壤学杂志》2012,175(5):775-783
Information related to the growth of fine roots is important for understanding C allocation in trees and the mechanisms of C cycling in ecosystems. Observations using a camera or scanner embedded in the soil enabled us to obtain continuous images of fine‐root‐growth dynamics. However, these methods are still labor‐intensive because the image analysis has to be conducted manually. We developed an automated method for tracking movement or elongation of fine roots using a sequence of scanner images. We also show how data obtained with these methods can be used for calculating fine‐root behavior. Two A4‐size scanners were buried in a mixed forest in Japan and images were taken continuously from within the soil. We preprocessed these images by extracting the fine‐root area from the images and developed an automated calculation plug‐in we named A‐root for tracking growth movement of the tips of fine roots. A‐root and manual‐tracking results were compared using the same images. The results show the A‐root and manual‐tracking methods yielded similar levels of accuracy. The average growth rate of 17 fine roots tracked using the program was 0.16 mm h–1. The observation of the direction of growth in fine roots showed the direction may be influenced by the original root's growth where the fine roots branched, distribution of soil particles, other roots, and the force of gravity. The A‐root analysis also suggested there may be an interaction between speed of growth and changes in direction of growing fine roots. 相似文献
37.
Fukushima U Sato M Okano S Aramaki Y Ito H Yoshioka K Oyamada T Uechi M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(3):311-313
A five-year-old male Shih-Tzu dog presented with severe vomiting and weight loss. The clinical signs were successfully improved by an eight-day treatment with an H(2)-receptor antagonist, gastrointestinal protectant and antibiotics. Ten days later, however, recurrence of vomiting was seen despite continuous medical treatment. Based on clinical signs and the results of various diagnostic tests including CBC, biochemical analysis, contrast radiography, and endoscopy, a duodenal or pancreatic neoplasm was suspected and exploratory laparotomy was conducted. Some swollen pancreatic regions were found, and biopsy of the pancreas indicated the diagnosis of a gastrin-secreting tumor. Consequently, based on a high serum gastrin level as well as clinical signs and immunohistological findings, we diagnosed the disease as canine gastrinoma, a rare tumor of the pancreas. 相似文献
38.
39.
40.
Tenma Hinako Tsunekawa Koki Fujiyoshi Riho Takai Hajime Hirose Masae Masai Nanami Sumi Kosuke Takihana Yuta Yanagisawa Sogen Tsuchida Kota Ohara Kenichi Jo Toshiaki Takagi Masaki Ota Akiko Iwata Hiroyoshi Yaoi Yuichi Minamoto Toshifumi 《Fisheries Science》2021,87(3):321-330
|
| 设为首页 | 免责声明 | 关于勤云 | 加入收藏 |
|
Copyright©北京勤云科技发展有限公司 京ICP备09084417号 |