著者
Kaito Kotani Kandai Doi Nana Ushine Takuya Kato Tatsuo Sato Masaki Nonagase Shin-ichi Hayama
出版者
The Japan Society of Medical Entomology and Zoology
雑誌
衛生動物 (ISSN:04247086)
巻号頁・発行日
vol.73, no.4, pp.157-159, 2022-12-25 (Released:2022-12-25)
参考文献数
20

An engorged ixodid tick was collected from a rescued short-tailed shearwater, Puffinus tenuirostris (Temminck), at Funabashi Sanbanse Seaside Park in Chiba Prefecture, Japan. Based on morphological features, we identified the specimen as Ixodes kerguelenensis (André and Colas-Belcour), which is a species known to infest seabirds in Oceania. To our knowledge, this is the first case report of I. kerguelenensis in Japan. The case of infestation to the shearwater suggests the possibility of the long-distance translocation of the tick in Oceanian region to Japan.
著者
Kandai Doi Fumiaki Yamasaki Takuya Kato Shin-ichi Hayama
出版者
Arachnological Society of Japan
雑誌
Acta Arachnologica (ISSN:00015202)
巻号頁・発行日
vol.70, no.1, pp.47-48, 2021-06-28 (Released:2021-07-05)
参考文献数
11

A pseudoscorpion was found in the underfur of a feral raccoon (Procyon lotor) captured in western Tokyo in December 2019. Based on the morphological features, we identified the specimen as Haplochernes sp. This arboreal pseudoscorpion rides other arthropods and small mammals for dispersion, but little is known that the species rides medium-sized mammals such as raccoons. To our knowledge, this is the first case report of Haplochernes sp. riding a feral raccoon. Given that raccoons are an invasive species in Japan, further records of pseudoscorpions riding feral raccoons may elucidate the relationship between feral raccoons and pseudoscorpions.
著者
Natsuko SUGIURA Kandai DOI Takuya KATO Tatsushi MORITA Shin-ichi HAYAMA
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.17-0092, (Released:2018-01-19)
被引用文献数
16

To examine outbreaks of mange in raccoon dogs (Nyctereutes procyonoides) with respect to population density, we analyzed camera trap videos, and isolated mites from raccoon dog carcasses. In a camera trapping survey, we categorized the skin condition of raccoon dogs, and used a number of independent videos to calculate the relative abundance index (RAI). The RAI of raccoon dogs with alopecia increased following an increase in the RAI of those without alopecia. Among 27 raccoon dog carcasses, 12 showed mange-compatible skin lesions. Sarcoptes scabiei was isolated from 11 of these raccoon dogs, indicating that sarcoptic mange was endemic in our study area. Therefore, a high relative population density may be a factor underlying epizootics of sarcoptic mange in raccoon dogs.
著者
Natsuko SUGIURA Kazuhiko OCHIAI Toshiaki YAMAMOTO Takuya KATO Yoshi KAWAMOTO Toshinori OMI Shin-ichi HAYAMA
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.82, no.4, pp.479-482, 2020 (Released:2020-04-09)
参考文献数
29
被引用文献数
1

We analyzed the genotypes of three pregnant females and their litters to investigate the phenomenon of multiple paternity in wild raccoon dogs (Nyctereutes procyonoides) using 17 microsatellite markers. If a female has mated with only one male during estrus, then the maximum number of paternal alleles will not exceed two among littermates with the same father. The results revealed two out of three litters had three or four paternal alleles at one or five microsatellite loci. Therefore, the female had mated with more than one male during estrus. To the best of our knowledge, the present study is the first to report the possibility of multiple paternity in wild raccoon dogs.
著者
Nana Ushine Shouta MM Nakayama Mayumi Ishizuka Takuya Kato Shin-ichi Hayama
出版者
The Japanese Society of Environmental Toxicology
雑誌
環境毒性学会誌 (ISSN:13440667)
巻号頁・発行日
vol.26, pp.25-37, 2023-06-22 (Released:2023-06-22)
参考文献数
83

Lead (Pb) is extensively used in industries and often inadvertently discharged into the environment. Despite some studies examining the effects of Pb pollution on raptors and waterfowl, its effects on other avian species have not been investigated. This study investigated the feeding selectivity of a black-headed gull (Chroicocephalus ridibundus) population using stable isotope ratios to determine the source of Pb pollution. Gulls in Tokyo and Mikawa Bay were captured from December 2016 to February 2017 and from December 2020 to March 2021, respectively. These gulls were measured 13C/12C carbon ratio (δ13C), and 15N/14N nitrogen ratio (δ15N). Blood Pb level (BLL) was measured gulls in Mikawa Bay. Based on the measurement values of δ15N, gulls were classified into two groups: primary and higher predator groups. No differences in stable isotope ratios were found between the two groups. The secondary consumers showed significantly high BLLs (P=0.002). BLLs during the wintering period were significantly higher in the primary consumer group. Our findings suggest that reducing Pb emissions, along with biological and chemical remediation of water sediment is required to prevent further Pb pollution and bioaccumulation in wild animals.
著者
Takuya KATO Yayoi ICHIDA Kazumi TEI Makoto ASANO Shin-ichi HAYAMA
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.71, no.11, pp.1473-1478, 2009 (Released:2009-12-04)
参考文献数
30
被引用文献数
5 5

In order to examine reproductive characteristics of feral raccoons in Kamakura, 335 raccoons were collected from March 2005 to March 2007. Raccoons were classified into five age classes: Class I, less than 5 months old; Class II, 5-11 months; Class III, 12-17 months; Class IV, 18-23 months; and Class V, over 23 months old. Females were examined for their age specific pregnancy rate and litter size. To determine when raccoon births occur in the region, birth months of fetuses were estimated by the fetal growth rate, and birth months of Class I individuals were examined by tooth eruption. From fetuses of 18 pregnant females and 47 Class I individuals, it was found that the raccoon births occur from February to October. Of 163 females examined, all of Class I-II females were nulliparous. Pregnancy rate was 47.6% in Class III females, which was significantly lower than 75.0% in Class IV and 78.1% in Class V. The litter size of fetuses ranged from 2 to 5, and 3.9 on average; and that of placental scars ranged from 1 to 7, 3.8 on average. Our findings suggest that parturition of raccoons is a bimodal distribution and age at first parturition may occur between 12 and 17 months old. In order to reduce the raccoon population successfully, females of all ages should be captured throughout the year.
著者
Eli Kaminuma Yukino Baba Masahiro Mochizuki Hirotaka Matsumoto Haruka Ozaki Toshitsugu Okayama Takuya Kato Shinya Oki Takatomo Fujisawa Yasukazu Nakamura Masanori Arita Osamu Ogasawara Hisashi Kashima Toshihisa Takagi
出版者
The Genetics Society of Japan
雑誌
Genes & Genetic Systems (ISSN:13417568)
巻号頁・発行日
pp.19-00034, (Released:2020-03-26)
参考文献数
37
被引用文献数
3

Recently, the prospect of applying machine learning tools for automating the process of annotation analysis of large-scale sequences from next-generation sequencers has raised the interest of researchers. However, finding research collaborators with knowledge of machine learning techniques is difficult for many experimental life scientists. One solution to this problem is to utilise the power of crowdsourcing. In this report, we describe how we investigated the potential of crowdsourced modelling for a life science task by conducting a machine learning competition, the DNA Data Bank of Japan (DDBJ) Data Analysis Challenge. In the challenge, participants predicted chromatin feature annotations from DNA sequences with competing models. The challenge engaged 38 participants, with a cumulative total of 360 model submissions. The performance of the top model resulted in an area under the curve (AUC) score of 0.95. Over the course of the competition, the overall performance of the submitted models improved by an AUC score of 0.30 from the first submitted model. Furthermore, the 1st- and 2nd-ranking models utilised external data such as genomic location and gene annotation information with specific domain knowledge. The effect of incorporating this domain knowledge led to improvements of approximately 5%–9%, as measured by the AUC scores. This report suggests that machine learning competitions will lead to the development of highly accurate machine learning models for use by experimental scientists unfamiliar with the complexities of data science.