Five pairs of ovaries were obtained from wild adult raccoon dogs (Nyctereutes procynoides) in November 2001, March and April 2002, and February and March 2003. Two of the 5 ovaries (March and April) contained corpora lutea. The purpose of the present study was to investigate immunolocalization of P450arom and its mRNA expression by reverse transcription-polymerase chain reaction (RT-PCR) in wild raccoon dog ovaries. Immunoreactive aromatase was detected in granulosa cells, internal theca cells and lutein cells. The P450arom mRNA was expressed in the ovaries of all wild raccoon dogs. We also determined 289bp nucleic acid sequence of P450arom using rapid amplification of cDNA (polymerase chain reaction). When compared to human, bovine and rat sequences, the nucleotide homology was 76.3%, 78.2%, and 72.6%, respectively. These results indicate that, in the wild raccoon dog, not only granulosa cells but also internal theca cells and lutein cells express P450arom and have the ability to metabolize androgens to estrogens.

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A survey of parasitic helminths in loaches (Misgurnus anguillicaudatus) imported from China to Japan was done in March 2000 and October 2001. The survey resulted in the detection of three species of nematode larvae (Spiroxys japonica, Gnathostoma hispidum, Contracaecum sp.), one species of adult nematode (Pseudocapiliaria tomentosa), six species of trematode metacercariae (Massaliatrema misgurni, Metorchis orientalis, Exorchis oviformis, Encyclometra japonica, Metacercaria hasegawai a, Echinostomatidae gen, sp.), one species of adult trematode (Allocreadium gotoi), one species of adult cestode (Paracaryophyllaeus gotoi) and one species of adult acanthocephala (Pallisentis sp.). These parasitic helminths need an intermediate host to complete each life cycle. The loaches play the part of the second, paratenic and final host. We are concerned about invasions of M, misgurni as an alien species into Japan.

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Because alien macaques (probably, Macaca mulatta) occur in the southern part of the Boso Peninsula, Japan, there is a possibility that their parasites and/or other pathogens may infect Japanese macaques (M.fuscata). To verify the possibility, this study was conducted mainly on parasites that included protozoan, helminth and arthropod, and other pathogens including Rickettsia and the Borna virus of 50 free ranging Japanese macaques in the peninsula. Consequently, 5 arthropod and nematode parasite species common to the Japanese macaque, namely Pedicinus obtusus, P.eurygaster, Streptopharagus pigmentatus, Strongyloides fulleborni, and Trichuris trichiura, were obtained in this survey. It is the first record of sites where Pedicinus spp. are seen in a host species.Coccidia and Babesia sp. were not obtained. Coxciella and the Borna virus from the same host samples will be published elsewhere.

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The incidence and occurrence of haematozoa (Haemoproteus sp.) was assessed from 98 blood slide samples from 70 individual of wild or captive Blakiston's Owls (Ketupa blakistoni) collected in Hokkaido, Japan, from 1994 to 1999. The samples derived from 7 individuals were positive for protozoa. Ages of positive host individuals were 2 months (1 wild), 7 months (1 wild) and over 12 months (5 wild). From the breeding season of the avian species, it is possible that infection of the young occurs in the nest. Because Haemoproteus sp. is occasionally pathogenic in avian young, the present result needs to be noted from conservation and clinical viewpoints. Further, as host-specificity of haematozoa is relatively low among several avian species, a more detail epidemiological survey that includes other owl species in Hokkaido will be needed.

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Relationships between the prevalence of alveolar hydatid (Echinococcus muitilocularis) in red foxes (Vulpes vulpes) captured in 74 regions of Hokkaido, Japan from 1985 to 1990 and some regional environmental factors (including population density of voles, temperature, snowfall depth, mean degree of slope, mean altitude, human population density, etc.) were examined using simple and multiple regression analysis methods. Eight explanatory variables were selected from 15 types of candidate variables belonging to eight respective categories of the regional environmental factors, based on the simple regression analysis. In the multiple regression analysis, only two of these eight explanatory variables were selected with a stepwise process, and the following model was obtained: Y=0.00979X_1-0.00037X_2+0.23833 (Y: arcsin-root transformed prevalence of E. multilocularis in foxes, X_1: captive number of voles in September, X_2: number of days with snowfall deeper than 50 cm, r=0.32180, P=0.0001). The higher density of the voles is supposed to make the establishment of the life cycle of this cestode species more successful. The negative influence of deeper snowfall on the prevalence is attributable to the lower predation pressure on the voles by the foxes in deeper snowfall, which suppresses the hunting behavior of the foxes.

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Three sub-adult Steller's Sea-Eagles (Haliaeetus pelagicus) kept in captivity during 4-6 weeks were released with radio-transmitters at the Shiretoko museum in Hokkaido, 1996. One eagle released in January stayed around the museum for three days. After five days of releasing, this eagle moved to coast at a distance of about 40 km from the museum and fed a dead whale drifted ashore with other wild eagles. Then, it was located at some lakes in the eastern region of Hokkaido, feeding fish discarded by fishermen, until early April. Other two eagles were released in July and one eagle of the two stayed around the museum for eight days and then moved to a lake at a distance of about 20 km from the museum. It was failed to locate after four day staying at the lake. Another eagle was failed to locate after five day staying around the museum, but it was found dead by lead poisoning at Akan town on April 1998. In this study, it was unknown whether Steller's Sea-Eagles released in summer left Hokkaido safely and immediately toward their summering areas. Eagles remained at the near places of the releasing site more than a few days after the releasing. Therefore, the releasing should be carried out at the sites which close to suitable feeding sites, have fewer possibilities of human disturbances and of the accidents by such as cars or electricity, and retain forests for roosting and perches.

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The liver was anatomically examined in a dead body of the orang-utan. Since each lobe was not ventrally protruded in the orang-utan, the liver appeared a regular square from the visceral aspect. The area data were obtained in 20 horizontal sections by means of the CT scanning. We pointed out that the volume and the weight were concentrated in the dorso-ventrally middle area, but not in the extremely ventral or dorsal margins in the liver. We suggest that its morphological characteristics may be adaptational to fix the liver in the visceral cavity in a condition of the cranio-caudally-directioned gravitation.

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We considered a skull of Canis preserved at a private house in Yamanashi Prefecture as that of Japanese wolf, Canis hodophilax. The size was 126.3 mm in zygomatic breadth, 107.9 mm in median palatal length and 38.2 mm in least breadth between orbits. The dorso-ventrally smaller frontal bone and caudo-laterally enlarged zygomatic arch could be observed. The rostro-cranial separation of the rostral alar foramen and the hollow in the median part of the posterior margin of the palatine bone were confirmed. The most dorsal region of the zygomatic arch consisted of the zygomatic process of the temporal bone. Both osteometircal and non-metrical characters demonstrated that the material was the skull of the extinct Japanese wolf. In addition the CT (computed tomography) imaging analysis pointed out that the nasal meatus was separated into the dorsal, medial and ventral nasal parts, and that the meatus possessed complicated structure in nasal cavity as well as in the domesticated dog. The distinct nasal septum cartilage and dorso-ventrally narrow frontal sinus could be seen in CT images. These CT data will help us to discuss the olfactory function in the Japanese wolf.

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Four internal parasite species, viz. Inermicapsifer hyracis (Cestoda: Anoplocephaliidae), I. cf. beveridgei, Grassenema procaviae (Nematoda: Atractidae) and Eimeria dendrohyracis (Protozoa: Eimeriidae) were detected from captive five Cape hyraxes (Procavia capensis) in Gunma Safari Park, Gunma Pref., Japan. These findings except for that of I. hyracis were first records In Japan.

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Using the non-destructive CT section methods, the hip joint was observed in an adult carcass and late stage fetus of the orang-utan. The macroscopic dissection was also carried out in an adult carcass. The CT images pointed out that the late stage fetus did not possess the ligament of head of femur as well as in the adult. The ligament completely disappeared at least in the late stage fetus of the orang-utan. From the macroscopic observation in the adult, the two thick parts of the iliofemoral ligament, the thin pubofemoral ligament, and the well-developed ischiofemoral ligament were confirmed, however the ligament of head of femur was not also detected between the acetabulum and the head of the femur as described in some former studies. The CT images helped us to confirm the structure of the hip joint as a non-destructive method.

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A mixture of medetomidine (60 μg/kg) and ketamine (4 mg/kg) can effectively immobilize Hokkaido sika deer, and atipamezole rapidly reverses the effect. However, it is difficult to administer the required dosage of the mixture for induction by a projected syringe because of the low (1 mg/ml) concentration of commercial medetomidine. Thus we lyophilized commercial medetomidine to increase its concentration (up to 10 mg/ml) and prepared a mixture to immobilize sika deers. The effect of the lyophilized medetomidine - ketamine mixture was similar to that of the commercial medetomidine - ketamine mixture. No case of death caused by immobilization using the new mixture was observed during our study. We concluded that the new mixture was safe to use for the immobilization of sika deer.

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The antagonism of atipamezole to xylazine was examined in Hokkaido sika deer (Cervus nippon yesoensis). Seventeen free-ranging sika deer were immobilized with a combination of xylazine (2.0 ± 0.1 mg/kg ; mean ± SE) and ketamine (6.0 ± 0.3 mg/kg) for 52.1 ± 3.2 min. The animals were administered atipamezole intramuscularly at xylazine:atipamezole dose ratios of 10 : 1 (n=5), 3 : 1 (n=6) and 2 : 1 (n=6). Rapid recoveries were achieved with 7.0 ± 3.2, 5.0 ± 2.6 and 5.2 ± 2.5 min for each dose group, respectively. No dose-dependent effects of atipamezole in the recovery time were observed. Atipamezole was effective in reversing xylazine-ketamine induced immobilization in sika deer.

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A 5-year-old female spectacled bear (Tremarctos ornatus) had pruritic eczema all over the body surface. Clinical signs were eczema with severe pruritus, epiphora, blepharoedema and sneeze. Hematological test showed increased WBC and eosinophils in number. Biochemical test showed significantly high value of LDH. Antihistamines had no effect for the symptoms. The bear was treated with prednisolone, and the symptoms were improved. After the bear moved from Yokohama to Hokkaido, these symptoms were disappeared. This skin disease was considered atopic dermatitis because of the periodicity of symptoms according to seasons, severe pruritus, eosinophilia, effect of corticosteroid and disappearance of clinical signs due to the change of living place.

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