著者
Satoru TERAI Hideki ENDO Worawut RERKAMNUAYCHOKE Eiichi HONDO Srihadi AGUNGPRIYONO Nobuo KITAMURA Masamichi KUROHMARU Junpei KIMURA Yoshihiro HAYASHI Takao NISHIDA Junzo YAMADA
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.60, no.10, pp.1097-1105, 1998 (Released:2001-10-06)
参考文献数
15
被引用文献数
6 8

The lesser mouse deer (Tragulus javanicus) is one of the most primitive ruminants. Skulls of lesser mouse deer were measured to evaluate their growth. The age was estimated from the eruption and attrition of molars on the mandible. A total of 95 specimens was divided into five age groups, and the growth pattern in each sex was established for some measurements. The relative growth coefficients were calculated for the head and body length and several parts of the cranium and mandible against the profile length. Sexual dimorphism could not be found on the skull in any age group except for measurements related to the upper canine. However, females showed a higher value in head and body length in the oldest group. This feature was consistent with an interpretation of mouse deer society as monogamous. Growth was more rapid in length than in width. Various statistical analyses showed that the visceral cranium related to masticatory facility was much better developed than the neurocranium. However, observations on the shape of the mandible ramus and of the premolars implied that the masticatory function was not suitable for taking roughage. This speculation agreed with previous reports on the feeding habits and digestive organs of the mouse deer.
著者
Hideki ENDO Daishiro YAMAGIWA Kazuyoshi ARISHIMA Masako YAMAMOTO Motoki SASAKI Yoshihiro HAYASHI Toshio KAMIYA
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.61, no.10, pp.1137-1141, 1999-10-25 (Released:2000-04-12)
参考文献数
16
被引用文献数
4 6

The MRI examination was carried out in a formalin-fixed specimen of the Ganges River dolphin (Platanista gangetica), one of the evolutionary primitive species of cetaceans. We could morphologically elucidate the tracheobronchial ramification in the intact whole body. We demonstrated from the MRI sections that the characteristic tracheal bronchus branches from the trachea at the cranial portion. These findings suggest the phylogenetic relationships between cetaceans and artiodactyls. The left bronchus is obviously larger in diameter than the right one. We suggest that the right bronchus has smaller capacity of gas exchange than the left one, because the dolphin possesses the tracheal bronchus in the right lung. The MRI method will be important in the non-invasive study of the anatomy in endangered animal carcass as Ganges River dolphin.
著者
Hideki Endo Kimiyuki Tsuchiya
出版者
日本哺乳類学会
雑誌
Mammal Study (ISSN:13434152)
巻号頁・発行日
vol.31, no.1, pp.47-57, 2006 (Released:2006-07-08)
参考文献数
25
被引用文献数
10

A new species of Ryukyu spiny rat, Tokudaia tokunoshimensis was described in the specimens originating from Tokunoshima Island in the southernmost region of Japan. The populations of Tokudaia are separately distributed only in Amami-Oshima, Tokunoshima, and Okinawa-jima Islands. We have described the osteological and external morphological characteristics and clarified the osteometrical distinctions among the three populations using the skull and skin collections. All external dimensions of head and body length, tail length, hindfoot length and ear length were larger in the Tokunoshima population than in the other two in mean value. The raw osteometrical data separated the Tokunoshima Island population from the other two in all measurements except for the length of molar row in the Okinawa-jima Island population. The principal component analysis also demonstrated that the skulls from the Tokunoshima Island population were morphologically distinct from those of the other populations. Here, from these findings, we point out that the Tokunoshima population of Tokudaia should be regarded as an independent species from the two other populations.