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Many tick-borne pathogens (TBPs) are present in wildlife. The objective of this study is to reveal the role of wild bears in maintaining TBPs. A total of 49 brown bears (Ursus arctos yesoensis) from Hokkaido, and 18 Japanese black bears (Ursus thibetanus japonicus) from Tochigi, and 66 Japanese black bears from Nagano were examined by two molecular methods, reverse line blot (RLB) hybridization, and nested PCR. A total of 5 TBPs (Hepatozoon ursi, Babesia sp. UR2-like group, Cytauxzoon sp. UR1, Babesia sp. UR1, and Babesia microti) were detected from bear blood DNA samples. B. microti was detected from blood DNA samples of Japanese black bear for the first time, with the prevalence of 6.0% (5/84). Out of detected pathogens, H. ursi, Babesia sp. UR2-like pathogens, and Cytauxzoon sp. UR1 were considered as three of the most prevalent TBPs in bears. The prevalence of H. ursi were significantly higher in Japanese black bear (0% vs 96.4%) while that of Babesia sp. UR2-like group was higher in Hokkaido brown bears (89.8% vs 40.5%). The prevalence of Babesia sp. UR1 were significantly higher in Japanese black bears from Tochigi (44.4%), comparing with those from Nagano (18.2%). The prevalence of the detected TBPs were significantly higher in adult bears, comparing with those in younger bears. The present study suggests that Japanese bear species contribute in the transmission of several TBPs in Japan. The expanding distribution of bears might cause the accidental transmission of TBPs to humans and domestic animals.

For bears, numerous associations between biotic and abiotic factors have been reported to correlate with the timing of den entry and emergence; however, an analysis showing which factors influence the timing of den entry and emergence has not been performed enough. In this study, a generalized linear mixed model was generated using 66 entry dates for 26 females and 40 entry dates for 26 males, and 56 emergence dates for 26 females and 25 emergence dates for 18 males between 1999 and 2012. Regarding factors for den entry, the average temperature in November and mast production of Mongolian oaks were significant for both males and females. For the date of den emergence, the average temperature in March affected strongly. For males, good mast production of Mongolian oaks in the previous year was found to be associated with early den emergence. For females, the presence of newborns had a significant influence on their den entry and emergence. This study indicated that denning behavior appears to be regulated by several abiotic and biotic factors and regulation factors are sex specific.

We characterized annual and seasonal home ranges (HR) of 27 female Asiatic black bears (Ursus thibetanus) during 2003–11 in Karuizawa, Nagano Prefecture, Japan. Mean annual HR size for bears calculated by the 95% fixed kernel method was 10.0 km2 (SD = 8.5) and differed depending on the year. However, annual HR sizes were not affected by reproductive status (with or without cubs) or age (subadult or adult). Home ranges tended to be larger in summer than in autumn. We speculate that a contributing factor to differences in HR size was annual or seasonal fluctuation of food resources. Annual shifts in HR centers and HR overlaps were estimated to be 1.2 km (SD = 0.9) and 0.55 km (SD = 0.13), respectively. Seasonal shifts in HR centers and seasonal overlaps were 1.1 km (SD = 1.1) and 0.54 km (SD = 0.12), respectively. Together, these results suggest that female Asiatic black bears in our study area do not migrate long distances seasonally or annually.

Graduate School of Agriculture, Hokkaido University, Sapporo 060-0809, JapanIn understanding the mechanism of population dynamicsof large mammals, it is essential to clarify the mortalityfactor. For ruminants, birth size is a major factor of neo-natal survival because smaller neonates are more suscep-tible to exposure (Haughey 1980; English and Mullery1992) and vulnerable to predators (Singer et al. 1997).Birth size is commonly related to maternal body sizewithin and across species (Clutton-Brock 1991). Thefetus/neonate-mother proportion may be a consequenceof developmental or morphological constraints (MaynardSmith et al. 1985). For example, it is well known thatfetomaternal disproportion (FMD) causes dystocia, oftenresulting in high fetal/neonatal mortality in domesticruminants (cattle, Johnson et al. 1988; Schwabe and Hall1989; Noakes 1997; West 1997: sheep, McSporran andFielden 1979; Thomas 1990; Dwyer 2003). However,dystocia in wild ruminants has been scarcely reported indetail. This is partly because dystocia may rarely occuras a consequence of natural selection toward optimalbirth size (mass) for mother and offspring (Clutton-Brock 1991), and/or dystocia may be simply difficult todetect in the field. In fact, neonatal mortality in prong-horn Antilocapra americana was caused partly bydystocia (1.8%) but mostly by trauma (61.8%) due topredation (Dunbar et al. 1999). Also, dystocia causedmortality of adult females (

Herd composition counts (HCC) are commonly used to assess population status in deer. We evaluated the reliability of HCC of sika deer (Cervus nippon Temminck) using repeated counts and by comparing estimated sex ratios and calf-to-female ratios of marked deer on Nakanoshima Island, Hokkaido, Japan between April 1999 and October 2000. Although both total counts and sex and age ratios fluctuated greatly by month, seasonal changes showed a relatively small variance. This suggested that seasonal changes in behavior within sex and age classes contributed to biased ratio estimates obtained from HCC. Route counts should be used as a relative population abundance index with estimates of detection probability, especially for females. Adult sex ratios and age ratios from HCC were unbiased during the rutting season (October–November), and age ratios in spring could be used if yearlings are counted as adults.

Ten free-ranging female sika deer (Cervus nippon) were captured to obtain the reference values for acid-base status and blood gas when immobilized with the combination of medetomidine and ketamine. The mean +/- SE of PaCO2, PaO2, and HCO3- were 58.1 +/- 6.1 mmHg, 58.8 +/- 6.4 mmHg, and 36.0 +/- 4.4 mmol/l, respectively. Although acidosis and alkalosis occurred in three and two animals, respectively, no serious conditions were observed. The blood values, however, suggest that some degree of hypoxemia and respiratory acidosis with metabolic alkalosis are developed. The trapped deer showed a significantly higher than normal rectal temperature reflective of exertion.

p70 S6 kinase (p70 S6K) has been implicated in the regulation of cell cycle progression. However, the mechanism of its activation is not fully understood. In the present work, evidence is provided that an atypical protein kinase C (PKC) isotype, PKClambda, is indispensable, but not sufficient, for the activation of p70 S6K. Both the regulatory and kinase domains of PKClambda associate directly with p70 S6K. Overexpression of the kinase domain without kinase activity or the regulatory domain of PKClambda results in the suppression of the serum-induced activation of p70 S6K. In addition, two types of dominant-negative mutants of PKClambda, as well as a kinase-deficient mutant of p70 S6K, suppress serum-induced DNA synthesis and E2F activation. The overexpresion of the active form of PKClambda, however, fails to activate p70 S6K. These results suggest that PKClambda is a mediator in the regulation of p70 S6K activity and plays an important role in cell cycle progression.

We performed microsatellite paternity analyses of two Asian black bear Ursus thibetanus littermates with a known mother. Using Cervus 3.0, we identified the probable father among 17 candidate fathers for Cub 1, but failed to identify a probable father for Cub 2. Cub 1 and her probable father shared at least one allele at all 13 loci. In contrast, Cub 2 and the probable father of Cub 1 had mismatching alleles at eight loci, indicating that the two cubs are offspring of different fathers. This is probably the first evidence for multiple paternity in Asian black bears.