title: Reproductive traits of the Ryukyu long-furred rat (Diplothrix legata) on Okinawa-jima Island.
abstract: The Ryukyu long-furred rat, Diplothrix legata, is a large rodent distributed only on Amami-ohshima Island, Tokuno-shima Island and Okinawa-jima Island, Japan. This animal is endangered as a result of deforestation, predation by introduced carnivores and mortality caused by vehicles. We performed theriogenological examinations of 32 male and 25 female Ryukyu long-furred rats carcasses collected from wild populations on northern Okinawa-jima Island from December 2005 to September 2013. Adult males had remarkably large preputial glands. Seminiferous diameter of adult was significantly small (136 ± 28 µm, n=8) from April to August. Numerous spermatozoa were observed from September through February, and seminiferous diameter was significantly large (216 ± 27 µm, n=12) during this time in adults; testes length changed in a similar pattern. These findings indicate that the mating season may occur from September through February. Size (body length) at sexual maturity was estimated to be >560 mm in both sexes. From observation of corpora lutea and placental scars, litter size was estimated to range from 2 to 12 (average=6, n=4). These results provide fundamental knowledge that will be beneficial for in situ and ex situ conservation of this rare species.
authors: Ecological Genetics Analysis Section, Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan.
authors: Tsukasa
authors: T
authors: Okano
authors: Katsuhi
authors: K
authors: Nakata
authors: Yumiko
authors: Y
authors: Nakaya
authors: Takashi
authors: T
authors: Nagamine
authors: Manabu
authors: M
authors: Onuma
mesh_terms: D000818:Animals; D001837:Body Weights and Measures; D003247:Conservation of Natural Resources / Q000379:methods*; D056727:Endangered Species; D005260:Female; D062312:Islands; D007564:Japan; D008098:Litter Size; D008297:Male; D051189:Murinae / Q000502:physiology*; D012098:Reproduction / Q000502:physiology*; D012621:Seasons
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