Vertebral Formula in Red-Crowned Crane (Grus japonensis) and Hooded Crane (Grus monacha)
| Autor: | Hiroyuki Masatomi, Masako Inoue, Kunikazu Momose, Akiko Uebayashi, Ippei Muneuchi, Sayaka Nishikawa, Takeo Hiraga, Ryoji Shimura, Nobuhiro Yasuda, Haruka Sakamoto, Hiromi Ueda, Hiroki Teraoka |
|---|---|
| Rok vydání: | 2014 |
| Předmět: | |
| Zdroj: | Journal of Veterinary Medical Science. 76:503-508 |
| ISSN: | 1347-7439 0916-7250 |
| DOI: | 10.1292/jvms.13-0295 |
| Popis: | The Red-crowned Crane (Grus japonensis) is one of the rarest crane species. The total wild population in the world is only about 2,800. There are two separated populations: a migratory population in the east Eurasian Continent of north-east Asia (continental population) and a non-migratory population in eastern Hokkaido, Japan (island population) [15, 18, 19]. The island population has steadily grown from a very small number (estimated at around 60) in the 1950s to over 1,300 birds mainly due to artificial feeding in winter [17]. On the other hand, the Hooded Crane (Grus monacha) is migratory and winters in Izumi, Kagoshima Prefecture, Japan, and its population exceeds 10,000, which is about eight-time larger than that of the Hokkaido population of Red-crowned cranes [5]. These two species of cranes and the White-naped Crane (Grus vipio) are major species in Japan, and these birds and their habitats are designated as special natural treasures of Japan, because of their scarcity, preciousness and beauty. Recently, based on results of mitochondrial DNA analysis, it has been shown that only two haplotypes exist in the island population, whereas seven types are present in the continental population of Red-crowned cranes [10]. On the other hand, ten types have been detected from Hooded cranes dead in Izumi [1]. Thus, the island population of Red-crowned cranes is severely deficient in genetic diversity compared to the continental one and Hooded cranes, possibly due to a “bottleneck” effect [10, 17]. There is concern about the scarce diversity, which might lead to the serious declines of immunoreactivity, adaptability and other properties in Red-crowned cranes in Hokkaido [17]. The number of vertebrae varies greatly among different vertebrate species, ranging from as few as six in some frogs to as many as several hundred in some snakes and fish [8]. Almost all mammals have seven cervical vertebrae (Cs), a number that remains remarkably constant [6]. On the other hand, various numbers of C have been reported even in domestic birds: for example, 12 in pigeons, 14 in chickens and ducks and 17 in geese [21]. However, little is known about the numbers of thoracic vertebrae (Ts), lumbar vertebrae (Ls), sacral vertebrae (Ss) and coccygeal vertebrae (Cos) as well as the pattern and variation of vertebral formula in domesticated birds [16, 21], and there has been a few report about the vertebral formula in wild birds including cranes. We collected Red-crowned and Hooded cranes, found dead or moribund in each field, and observed skeletons with focus on the vertebral column. In this study, we clarified the vertebral formulas for two crane species, which showed numerical variation of each part of the vertebrae. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|