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Red-crowned cranes (Grus japonensis) are distributed separately in the east Eurasian Continent (continental population) and in Hokkaido, Japan (island population). The island population is sedentary in eastern Hokkaido and has increased from a very small number of cranes to over 1,300, thus giving rise to the problem of poor genetic diversity. While, Hooded cranes (Grus monacha), which migrate from the east Eurasian Continent and winter mainly in Izumi, Kagoshima Prefecture, Japan, are about eight-time larger than the island population of Red-crowned cranes. We collected whole bodies of these two species, found dead or moribund in eastern Hokkaido and in Izumi, and observed skeletons with focus on vertebral formula. Numbers of cervical vertebrae (Cs), thoracic vertebrae (Ts), vertebrae composing the synsacrum (Sa) and free coccygeal vertebrae (free Cos) in 22 Red-crowned cranes were 17 or 18, 9-11, 13 or 14 and 7 or 8, respectively. Total number of vertebrae was 47, 48 or 49, and the vertebral formula was divided into three types including 9 sub-types. Numbers of Cs, Ts, vertebrae composing the Sa and free Cos in 25 Hooded cranes were 17 or 18, 9 or 10, 12-14 and 6-8, respectively. Total number of vertebrae was 46, 47, 48 or 49, and the vertebral formula was divided into four types including 14 sub-types. Our findings clearly showed various numerical vertebral patterns in both crane species; however, these variations in the vertebral formula may be unrelated to the genetic diversity.

A 33 month-old male flying squirrel kept in a zoo developed progressive dyspnea and died. Macroscopically, the liver and lung were enlarged with numerous nodular vesicles. Histologically, these organs were replaced by numerous collapsed vesicles demarcated by fibrous tissues. The cysts lined by a cellular, germinal layer contained numerous brood capsules with abundant production of well-developed protoscolices. Protoscolices were about 80-100 μm in diameter, and had hooks being visible as refractive structures. This zoo locates in the east of Hokkaido where is an endemic area of Echinococcus multilocularis infection. From epidemiology and pathological findings, this animal was diagnosed as E.multilocularis infection. This report describes the pathology of the first case of E. multilocularis infection in a flying squirrel.

A 33-year-old red-crowned crane (Grus japonensis) had a diffuse intestinal thickening from the duodenum to colon. Microscopically, neoplastic cells were arranged in sheets and occasionally nests or cords without gland or squamous differentiation. Metastatic tumor cells were found in the lungs, heart, kidneys and adrenal glands. Immunohistochemically, the neoplastic cells were strongly positive for pan-cytokeratin and cytokeratin 8 and 18 and only partly positive for E-cadherin antibodies. Immunostaining for CD3 was positive in normal lymphocytes, and NSE was also positive in normal nerve fibers. But, the neoplastic cells were not immunoreactive to CD3 and NSE. Based on the histological features and the epithelial characteristics in the immunohistochemical stain, the present case was diagnosed as undifferentiated carcinoma originating from the intestine. Interestingly, the neoplastic cells showed a unique growth pattern; they never invaded the submucosa or muscularis throughout the intestine, whereas they spread lymphogenously or hematogenously to other organs.

Red-crowned (or Japanese) cranes Grus japonensis are native to eastern Hokkaido, Japan--the island population, and mainland Asia--the continental population that migrates from breeding grounds along the Amur River Basin to winter in east China and the Korean Peninsula. The island population was reduced to about 50-60 birds in early part of the 20th century. Since 1950s, the population has increased to more than 1,300 as a consequence of human-provided food in winter, resulted in change of their habitats and food resource. From the carcasses of 284 wild cranes from the island population, collected in Hokkaido since 1976 until 2010, we measured six physical parameters (body weight and lengths of body, wing, tarsus, tail and exposed culmen) and divided into groups by sex and three developmental stages (juvenile, yearling and adult). All parameters of males were larger than those of females at the same stage. Total body length of females tends to grow up earlier than males, in contrast to body weight. Obvious time trends were not observed in these all parameters during 34 years for these six categories measured, except total length of male juveniles, which showed a significant increasing trend. These results provide the first extensive data on body size and mass in the wild red-crowned cranes.