羽山 伸一

Lead (Pb), an environmental pollutant, has been widely reported to have contaminated mammals, including humans and birds. This study focuses on the effects of Pb pollution on avian influenza virus (AIV) antibody production. A total of 170 black-headed gulls (Chroicocephalus ridibundus) were captured in Tokyo Bay (TBP) from January 2019 to April 2020 and in Mikawa Bay (MBP) from November 2019 to April 2021. The gulls were weighed, subjected to blood sampling, and released with a ring band on their tarsus. The samples were used to measure blood Pb levels (BLL) and AIV-specific antibodies. The BLL were compared using the Wilcoxon two-sample test between the period when black-headed gulls arrived and the wintering period, defined by the number of gulls counted in each area. A significant increase was found in the TBP. A decrease in BLL significantly increased antibody titer during wintering in TBP and MBP. Pb pollution had a negative effect on the production of AIV antibodies. These findings suggest that wild birds that were contaminated by Pb in the environment may facilitate the spread of zoonotic diseases, further increasing the possibility that environmental pollutants may threaten human health.

Wild Japanese monkeys (Macaca fuscata) were exposed to radiation after the Fukushima Daiichi nuclear accident in 2011. To clarify the biological effects of radiation exposure on their fetal growth, pregnant monkeys and their fetuses were analyzed. These animals were collected between 2008 and 2020 (before and after the accident in 2011) living in Fukushima City, approximately 70 km from the nuclear power plant. Multiple regression analyses were conducted with fetal body weight (FBW) and fetal head circumference (FHS) as objective variables, and maternal and fetal factors as explanatory variables. The maternal factors were relative exposure dose rate (REDR), age, body weight, body length, fat index, and parity. The fetal factors were crown ramp length (CRL) and sex. Multiple regression analyses showed that FBR and FHS growth were positively associated with CRL, maternal body length, and negatively associated with REDR. Since the relative growth of FBR and FHS to CRL decreased with increasing REDR, radiation exposure due to the nuclear accident may have contributed to the delayed fetal growth observed in Japanese monkeys.

In forensic pathology, it is important to detect and recover as evidence residual metal particles and projectiles when evaluating potential gunshot wounds. This process can be challenging when the bullets are fragmented. This report presents our experience using multiple modalities to analyze the wound of an illegally killed Japanese serow (Capricornis crispus) found in a mountainous region without its head and hind limbs. We performed postmortem computed tomography (PMCT) and necropsy that showed a distant-range gunshot wound of the neck likely created by a centerfire rifle. A postmortem cut through the neck and absent head precluded a complete evaluation. To determine the composition of the metal-like fragments in the neck, sampling and metal analysis were performed in two ways. Samples extracted from the exposed wound surface without CT guidance were analyzed directly using inductively coupled plasma mass spectrometry (ICP-MS). Samples from the bone, muscles, and cervical cord extracted under CT guidance were analyzed using x-ray analytic microscopy (XGT-9000, HORIBA, Kyoto, Japan). In wound surface samples, silicon and iron were detected as the main components on ICP-MS, suggesting that the materials were gravel. The samples taken under CT guidance and analyzed with XGT-9000 revealed that the high-density CT areas were mainly composed of lead. Combining CT-guided sample extraction and XGT-9000 can be useful for retrieving true projectile fragments and avoiding the confusion created by erroneously sampling non-projectile surface materials.

Abstract Background The oriental eyeworm Thelazia callipaeda (Spirurida: Thelaziidae) is an emerging parasitic ocular nematode of carnivores and humans. In domestic animals and humans, the infection causes varying degrees of inflammation and lacrimation, and wild carnivores represent an important reservoir. In this study we examined the infection status and molecular characterization of T. callipaeda in two urban carnivores, raccoons Procyon lotor and wild Japanese raccoon dogs Nyctereutes viverrinus, in the Kanto region of Japan. Methods From January 2020 to December 2021, 193 carcasses including 178 raccoons and 15 raccoon dogs were examined for the presence of worms in the eye. The worms from infected animals (one worm per host) were morphologically identified as T. callipaeda. Worms (1–5 worms per host) were subjected to genetic analysis using mitochondrial cytochrome c oxidase subunit I gene sequences. Results The prevalence of T. callipaeda in raccoons and Japanese raccoon dogs was 20.2% (36/178) and 13.3% (2/15), respectively. The cox1 sequences from 56 worms from 38 animals revealed three haplotypes (h9, h10, and h12). Analysis of multiple worms for five raccoons showed co-infection of two different haplotypes (h9 and h10) in a single host. Comparing our data with published sequences, three sequences obtained from raccoons and raccoon dogs shared the same haplotypes as those reported in humans, dogs, and cats in Japan. Conclusions Our findings show a high prevalence of T. callipaeda in raccoons, suggesting that this invasive carnivore species serves as an important natural reservoir of T. callipaeda in the Kanto region of Japan, an area with the highest human population of the country. Graphical Abstract

Although the genetic distribution of introduced raccoons (Procyon lotor) in recent years is well known, few studies have examined their morphometrics, especially the relationships between sex and age in the introduced populations. The aim of this study was to describe the morphological characteristics of raccoons from parts of eastern and western Japan during their early invasion stages, focusing on the relationships between body length and the principal component of craniometrics, with region, sex, age class, body length, and body mass index using a regression model. The body length increased more in males than females and in the older age class, supporting the association with intrasexual selection and competition for food resources. Positive relationships for body length and body mass index were found in craniometric analyses, particularly regarding cranial size components, in addition to age class for both sexes, while cranial size also differed between regions for females. The relationship between body length and craniometrics was inconsistent with that of subspecies originating in North America. Given the sympatric distribution of haplotypes of multiple subspecies without reproductive-isolating barriers in North America and in several introduced areas, hybridization must have occurred prior to the introduction or naturalization of this species.

Leptospirosis is a zoonosis that affects humans and animals worldwide. Raccoons (Procyon lotor), adopted in urban environments, may act as potential reservoirs of Leptospira. We investigated the prevalence of pathogenic Leptospira in the kidney and urine samples of raccoons living in Tokyo, as well as anti-leptospiral antibodies in their serum, and aimed to examine the factors that expose raccoons to Leptospira. Polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) were used to detect leptospiral DNA and anti-leptospiral antibodies, respectively. Thirty-six of 156 raccoons (23.1%) were positive by PCR, and 16 of 165 raccoons (9.7%) were positive by ELISA. The prevalence and seroprevalence rates differed depending on the raccoon dispersal period. We used univariable logistic regression to estimate the environmental factors associated with pathogenic Leptospira and anti-leptospiral antibodies in raccoons. Significant differences were observed in the PCR results for the seasons (spring–summer) (p = 0.01), average monthly temperature (p < 0.01), and average monthly rainfall (p < 0.01). No significant difference was seen in the ELISA results, but raccoons in larger urban areas tended to have higher seroprevalence rates (p = 0.06). We identified a pattern of leptospiral spread in raccoon dispersal and environmental factors that expose raccoons to Leptospira.

Land-use patterns, climatic factors, and wildlife distributions have been suggested to have a role in shaping vector tick distributions. In the Tokyo metropolis and surrounding prefectures, these factors have rapidly changed over the last few decades. Here, we estimated the potential distributions of ticks based on the data of a 7-year tick survey at 134 sites in western Kanto, Japan. We focused on  6 tick species (Amblyomma testudinarium; Haemaphysalis flava; H. kitaokai; H. longicornis; H. megaspinosa; and Ixodes ovatus) using Maximum Entropy (MaxEnt) modeling based on the annual precipitation, snow depth; remote-sensing land-use patterns (Forest connectivity; Agricultural land; Urban; Open water; Deciduous broad-leaf forest; Deciduous needle-leaf forest; Evergreen broad-leaf forest; Evergreen needle-leaf forest; Bamboo forest; Grassland; Bareland), and the distributions of five common wildlife species [sika deer (Cervus nippon); wild boar (Sus scrofa); raccoon (Procyon lotor); raccoon dog (Nyctereutes procyonoides); masked palm civet (Paguma larvata)].

To investigate the seroprevalence of severe fever with thrombocytopenia syndrome (SFTS) among wild and companion animals on Tsushima Island, Japan, SFTS virus (SFTSV)-specific ELISA and virus-neutralizing tests were conducted on 50 wild boars, 71 Sika deer, 84 dogs, 323 domestic cats, and 6 Tsushima leopard cats. In total, 1 wild boar (1.8%), 2 dogs (2.4%), 7 domestic cats (2.2%), and 1 Tsushima leopard cat (16.7%) were positive for anti-SFTSV antibodies. Among the 11 positive animals, 10 were collected after 2019, and all were found on the southern part of the island. SFTSV, thus far, seems to be circulating within a limited area of Tsushima Island. To protect humans and animals, including endangered Tsushima leopard cats, from SFTSV infection, countermeasures are needed to prevent the spread of SFTSV on Tsushima Island.

Over the 10 years immediately after the Fukushima Daiichi nuclear accident, we measured the changes in the muscle 137Cs concentration (Bq/kg) of wild Japanese monkeys living in Fukushima City, which is located approximately 70 km from the Fukushima Daiichi Nuclear Power Plant. The muscle137Csconcentration, which was observed at a maximum of 13,500 Bq/kg immediately after the accident, had decreased to several hundred Bq/kg 10 years later. The muscle 137Cs concentration was significantly related to the soil contamination levels (10,000-30,000, 30,000-60,000, 60,000-100,000, and 100,000-300,000 Bq/m2), sex, age class (immature, mature), body weight (> 5000 g, 5000-10,000 g, < 10,000 g), and seasons (the cold period from December to April, the warm period from May to November).The value of muscle 137Cs concentration and the aggregated transfer factor (Tag: calculated by dividing muscle 137Cs concentration [Bq/kg] by soil 137Cs deposition density at the capture site [Bq/m2]) apparently decreased with time for several years. However, post hoc pairwise comparisons showed no difference from 2017 to 2020, and the accumulation of 137Cs in muscle may continue for some time.

傷病鳥は負傷原因だけでなくその個体の由来に関する情報を提供してくれる．2020年4月に滋賀県草津市で衰弱して救護された1個体フクロウStrix uralensis (Strigidae)を詳しく調べた．外貌の嘴と爪の状態から，飼育歴があると判定した．エゾフクロウS. u. japonica 3個体と本州の亜種フクロウ8個体，そしてキュウシュウフクロウS. u. fuscescens 2個体のサンプルとのミトコンドリアDNAを使った系統解析の結果，本個体は本州亜種あるいは九州亜種である可能性が考えられた．

BACKGROUND: Tick distributions have changed rapidly with changes in human activity, land-use patterns, climate, and wildlife distributions over the last few decades. METHODS: To estimate potential distributions of ticks, we conducted a tick survey at 134 locations in western Kanto, Japan. We estimated the potential distributions of six tick species (Amblyomma testudinarium Koch, 1844; Haemaphysalis flava Neumann, 1897; Haemaphysalis kitaokai Hoogstraal, 1969; Haemaphysalis longicornis Neumann, 1901; Haemaphysalis megaspinosa Saito, 1969; and Ixodes ovatus Neumann, 1899) using MaxEnt modeling based on climate patterns, land-use patterns, and the distributions of five common wildlife species: sika deer (Cervus nippon Temminck, 1838), wild boar (Sus scrofa Linnaeus, 1758), raccoon (Procyon lotor Linnaeus, 1758), Japanese raccoon dog (Nyctereutes procyonoides Gray, 1834), and masked palm civet (Paguma larvata C.E.H. Smith, 1827)). RESULTS: We collected 24,546 individuals of four genera and 16 tick species. Our models indicated that forest connectivity contributed to the distributions of six tick species and that raccoon distribution contributed to five tick species. Other than that, sika deer distribution contributed to H. kitaokai, and wild boar distribution, bamboo forest, and warm winter climate contributed specifically to A. testudinarium. CONCLUSIONS: Based on these results, the dispersal of some tick species toward residential areas and expanded distributions can be explained by the distribution of raccoons and by forest connectivity.

The Japanese serow (Capricornis crispus) and sika deer (Cervus nippon) in Japan are usually allopatric. However, a recent expansion in the distribution range of sika deer, combined with an increase in abundance, has resulted in an overlap of the distribution ranges of the two species. We examined the habitat selection and activity patterns of Japanese serows and sika deer using camera traps placed at 83 sites within a 210 km2 study area, where the distribution range of these two species has recently overlapped. Although both species were photographed throughout the study area, we observed a low spatial overlap between them. The Japanese serows selected steep slopes, and the sika deer selected areas far away from human settlements. In addition, the Japanese serows and sika deer exhibited temporal partitioning with diurnal and crepuscular activity patterns, respectively. The observed partitioning could be explained by differences in their species-specific habitat selections, rather than competition, because the photographic capture rate of the Japanese serows was not affected by that of the sika deer and vice versa. These partitioning behaviors are likely to reduce the rate of encounters between the two ungulates, which enables their coexistence considering the sika deer density remains low.

The Shimokita Peninsula in Aomori Prefecture, Japan, which is inhabited by Japanese monkeys (Macaca fuscata), is the northernmost habitat for wild primates in the world. This study was the first to determine the conception dates of specific individuals and estimate the pregnancy rate of wild populations in this region. The pregnancy rate of animals aged 5 years or more at delivery was estimated to be 40.9% (27/66). Conception dates of each fetus were also estimated using a regression line of Pig-tail monkeys (Macaca nemestrina), which are taxonomically related to Japanese monkeys and have a similar physique. The conception dates were distributed across 90 days between September 24th and December 23rd, with a mean conception date of November 4th (SD=22.3 days, n=53). Using these findings, the mean birth date was estimated as April 25th, more than two weeks earlier than the mean birth date in previous research determined using direct observations carried out over the past 20 years ago. Global warming due to climate change is thought to be one of the main causes of this difference.

BACKGROUND: In forensic medicine, the diatom test is used to diagnose drowning. Drowning and postmortem immersion can be distinguished by calculating the ratio of diatom concentration in the lungs and drowning water (L/W ratio). However, this claim was based on the unproven hypothesis that diatoms may be concentrated in the lungs due to respiratory movements. This study was conducted to examine whether the L/W ratio increased with experimental water injection. METHODS: A total of two experiments was performed using 22 non-drowned cat carcasses found on dry land. First, for the experimental postmortem immersion, we soaked seven whole-body cat carcasses in pond water for an hour. Second, the pond water was experimentally injected one or ten times into each harvested lung from seven and eight cats, respectively. In the diatom test, two diatom species (Aulacoseira ambigua and Discostella asterocostata) that were dominantly observed in pond water as well as other diatom species were counted separately. The L/W ratios of each cat were calculated. Univariate linear regression analysis was performed to demonstrate the association among L/W ratios and the three categories of the experiments. The L/W ratios of the two experiments were compared with those of drowning or postmortem immersion cases of humans or cats. RESULTS: It was revealed that the clear L/W ratio differences between the three groups (experimental postmortem immersion<0.02, 1-injection < 0.2, 10-injection > 0.9 for all diatom counting) were with statistically significant as proven by the univariate regression analyses. In actual cases of cats and humans, L/W ratios were>0.4 for drowning and<0.04 for postmortem immersion. CONCLUSION: The L/W ratio increased with multiple experimental water injections into the lungs, thereby verifying the validity of the diatom concentration test to diagnose drowning. The diatom test can be used to distinguish between drowning and postmortem immersion in humans and cats by calculating the L/W ratio.

A pseudoscorpion was found in the underfur of a feral raccoon (Procyon lotor) captured in western Tokyo in December 2019. Based on the morphological features, we identified the specimen as Haplochernes sp. This arboreal pseudoscorpion rides other arthropods and small mammals for dispersion, but little is known that the species rides medium-sized mammals such as raccoons. To our knowledge, this is the first case report of Haplochernes sp. riding a feral raccoon. Given that raccoons are an invasive species in Japan, further records of pseudoscorpions riding feral raccoons may elucidate the relationship between feral raccoons and pseudoscorpions.

Aim: Understanding patterns and processes of geographic genetic variation within and among closely related species is the essence of phylogeography. Japanese macaques, also called snow monkeys, have been extensively studied, particularly in the fields of sociobiology, ecology and experimental biology; however, our knowledge of their evolutionary history is relatively limited. In this study we aimed to elucidate the geographic patterns of genetic variation in Japanese macaques and the processes that underlie them. Location: Japan. Taxa: Japanese macaque, Macaca fuscata; rhesus macaque, M. mulatta; Taiwanese macaque, M. cyclopis. Methods: Double-digest restriction site-associated DNA (RAD) sequencing was used to identify genome-wide single nucleotide variants. We used fineRADstructure, ADMIXTURE and principal component analyses to estimate the genetic population structure. Phylogenetic relationships were then inferred based on neighbour-net, neighbour-joining, maximum likelihood and SVDquartets algorithms. We assessed gene flow using demographic inference and ABBA-BABA tests, and estimated past distributions during the Last Glacial Maximum (LGM) using ecological niche modelling. Results: Japanese macaques show a sister group relationship with a clade comprising Chinese rhesus, Indian rhesus and Taiwanese macaques. Japanese macaques comprise major north-eastern and south-western clades, with a boundary located near central Japan, and gene flow between the north-eastern and south-western lineages was detected. Refugia during the LGM were estimated to be distributed in limited areas along the south coasts of the Japanese archipelago. Main conclusions: Phylogeographic variation of Japanese macaques is likely due mainly to northeast–southwest divergence, which resulted from withdrawal into refugia during the glacial period, and subsequent gene flow.

Abstract Wild birds often require rehabilitation after collisions, even with no apparent injury. Information about aftermath of collisions is still scares. Here, we investigated external characteristics and clinical features of the internal organs of wild birds that experienced collision and compared them with birds admitted to rehabilitation center for other reasons. Necropsy was performed on 55 bird carcasses from Passeriformes and Coraciiform. Five external characteristics were recorded before necropsy including; cause of admission, keel score, life stage, fat score, and number of days before death. The median survival time was calculated by Kaplan-Meier estimates. Data on external and internal features were compared using univariate and multivariate multinomial regressions. There was no significant difference in the median survival time among the causes of admission: 1 day for collision, 2 days for trauma, and 2 days for malnutrition. Kidney discoloration was more significantly associated with collision than with other trauma (p = 0.01). Although no apparent kidney abnormality (including enlargement) were observed, anterior lobe was significantly larger than posterior lobe with collision compared with malnutrition (p = 0.045). Birds that experienced collision exhibited a higher fat score than malnourished birds (p = 0.03). Our results suggested that wild birds with abundant fat were more likely to be admitted due to collision. The gross characteristics of collision included kidney discoloration and anterior lobe extension, which was possibly due to rupture of renal blood vessels by blunt external force. From these findings, it was considered that collision caused major axis of anterior lobe significantly larger than posterior lobe, even though no abnormal finding in renal size such as hypertrophy was recognized. This was the first study to evaluate the cause of admission, necropsy results, and external characteristics in wild birds admitted to rehabilitation centers. Absolute cage rest should be adhered to restore renal function for those birds admitted due to collision, and handling and treatment should be minimized to avoid excess movement of the birds.

The raccoon (Procyon lotor) and masked palm civet (Paguma larvata) are introduced species in Japan and have become abundant in human-inhabited environments. We surveyed tick infestations and tick ingestion by introduced raccoons and masked palm civets captured in Hayama, Kanagawa Prefecture, Japan between November 2018 and January 2020. We collected ticks from the body surface of animals and tick capitula from the gastrointestinal contents. We collected 18,357 ticks identified as Haemaphysalis flava, Haemaphysalis megaspinosa, Haemaphysalis longicornis, Ixodes ovatus, Ixodes tanuki, and Amblyomma testudinarium from 58 of 60 raccoons and 152 ticks, identified as H. flava and I. tanuki, from 16 of 41 masked palm civets. Furthermore, we obtained 16 capitula from 12 % of raccoons and 106 capitula from 63 % of masked palm civets. Raccoons harbored a greater number of ticks (all stages of H. flava and adult I. tanuki) compared with masked palmed civets, whereas the latter species ingested a greater number of nymphal and larval ticks. The results of this study extend our understanding of the ecological roles of two introduced wildlife species. The raccoon may act as an ecological booster, thereby increasing the success rate of bloodmeals and reproduction in ticks. In contrast, the masked palm civet may act as an ecological trap by effectively grooming to remove ticks and prevent bloodmeals.

Since the re-emergence of a highly pathogenic avian influenza (HPAI) in 2004, outbreaks of the viral subtypes HPAI, H5N1, H5N8, and H5N6 in wild birds, poultry, and zoo birds have occurred in Japan. In 2008, a nation-wide avian influenza (AI) surveillance program was started for the early detection of the HPAI virus (HPAIV) and for the assessment of HPAIV infection among wild birds. In this study, we aimed to conduct an overview of the AI surveillance system of wild birds in Japan, including those in the regions and prefectures, to assess its overall performance and develop insights on its improvement. We analyzed past surveillance data in Japan and conducted questionnaire surveys for the officers in 11 regional branches of the Ministry of Environment and the nature conservation divisions of 47 prefectures to acquire details regarding those AI surveillance. We found that the early detection of HPAIV in wild birds was successfully achieved in only one of the five outbreak seasons during the 2008-2019 period in Japan, and the assessment of HPAIV infection had possibly not been adequate in the national surveillance system. In the winter season, AI surveillance in most prefectures were mainly conducted by means of passive surveillance through reported dead birds and active surveillance through collected waterbird feces. Conversely, less than half of the prefectures conducted bird monitoring, patrolling in migratory bird habitats, and AI antigen testing in rescued birds. In areas surrounding HPAI occurrence sites (<10 km), bird monitoring and patrolling efforts were enhanced. However, AI testing efforts in waterbird feces and rescued birds were decreased. The AI surveillance for endangered bird species and in national wildlife protection areas was conducted by the branches of the Ministry of Environment and by the prefectures. Based on our results, we concluded that for maximum efficiency, legislation which specialized in wildlife pathogens should be necessary to prepare adequate national budget and testing capacity for appropriate surveillance system with periodical assessment for surveillance results and the system.

<p>Carnus hemapterus Nitzsch (Diptera: Carnidae) was collected from a white-cheeked starling, Sturnus cineraceus Temminck in Chiba Prefecture, Honshu, Japan. Here, we report the white-cheeked starling as a new host for C. hemapterus.</p>

In order to elucidate the relationship between migration period and immunity related to susceptibility, we conducted research on Black-headed gulls (Chroicocephalus ridibundus). We captured 260 gulls and collected their peripheral blood. Their leukocyte (WBC) count, percentages of heterophils (Het) and lymphocytes (Lym), heterophil and lymphocyte ratio (H/L ratio), and CD4 and CD8α expression levels (CD4 and CD8α, respectively) were quantitatively analyzed over three migration periods (Autumn migration, Wintering, Spring migration). In Adult gulls, WBC counts and CD4 levels significantly increased. Moreover, the Het and H/L ratio decreased from the Autumn migration to Wintering. Conversely, only WBC counts and CD4 levels measurements significantly decreased from Wintering to Spring migration (P<0.05). The tested parameters of the Tokyo-bay population show a greater significant difference than the measurements of immunity of the Mikawa-bay population. This study suggests that the migratory period has a negative effect on an aspect of the immune system. Including the period-difference in the immune systems in the local population, it is necessary to investigate the relationship between the ecology of migratory birds and their immunity.

Although kinship (parent-offspring or siblings) contact has been suggested as a driving factor for sarcoptic mange epizootic in raccoon dogs (Nyctereutes procyonoides), no effect has been reported. In contrast, habitat fragmentation caused by urbanization may result in a high occurrence of sarcoptic mange, because habitat fragmentation may promote contact infection by increasing the population density of raccoon dogs. The habitat distribution of raccoon dogs may therefore influence epizootic sarcoptic mange. The genetic relationship between raccoon dogs was analyzed to examine Sarcoptes scabiei transmission between kin. The relationship between S. scabiei infection and the habitat of raccoon dogs was also investigated. Seventy-five raccoon dogs from Takasaki, Gunma prefecture, were examined from 2012 to 2018; 23 were infested with S. scabiei. The genotypes were determined using 17 microsatellite loci, and the relationships were categorized into four patterns by the ML-Relate software. There was no significant difference between infested pairs and other two pairs (Chi- squared test: χ2=0.034, df=1, P=0.85). Although it was difficult to predicate because the mortality rate was unclear in this study, kinship contact does not seem to be an important factor for sarcoptic mange epizootic. S. scabiei infection rates were significantly associated with the location of village sections (OR=1.55, 95% CI=1.11-2.17, P=0.011). It is suggested that direct/indirect contact between individuals living closely together is an important factor for the transmission of S. scabiei.

Investigating the cause of animal death is helpful to understand the reasons behind the interactions and conflicts between humans and animals. To further develop the cause of death investigation, we report a case of a Chinese spot-billed duck (Anas zonorhyncha) which hatched from a rescued duck and died 10 days after release. We inspected the duck's cause of death using an interview of concerned people, external body examination, necropsy, and genetic examinations. Based on the fractures, the main cause of death was determined to be a traffic accident. Furthermore, molecular tests helped to detect raccoon DNA in the visible bite wounds. This case shows that molecular biological method is one of the methods of clarify the animals'cause of death.

Few studies have evaluated immunosuppression due to lead accumulation below the overt toxicity threshold. If low levels of lead accumulation cause immunosuppression in birds, those birds could become more susceptible to pathogens. We aimed to determine if low levels of lead accumulation lead to immunosuppression in Black-headed gulls (Chroicocephalus ridibundus). Gulls were captured in Tokyo-bay and Mikawa-bay from January to April 2019. Their blood samples were analyzed for eight items. The data were analyzed to evaluate the correlation between lead concentrations and the variables from each bay. Lead was positively correlated with the percentage of heterophils and heterophil and lymphocyte ratio and negatively with lymphocytes. Thus, low lead accumulation levels may induce changes in percentage of the heterophils and lymphocyte.

© 2020 The Authors The effects of introduced mammal species on the ecology of parasites are often under investigated. The sika deeer, Cervus nippon, is host species of many hard ticks. We collected 8348 ticks on an island where sika deer were introduced. The most representative species was Haemaphysalis megaspinosa (n = 4198; 50.3%), followed by H. longicornis (n = 1945; 23.3%), H. cornigera (n = 1179; 14.1%), H. flava (n = 713; 8.5%), Ixodes turdus (n = 289; 3.7%), I. granulatus (n = 22; 0.3%), and H. hystricis (n = 2; <0.1%) on an island where sika deer were introduced. H. megaspinosa and H. hystricis have not previously been recorded on the Izu islands. The high abundance of H. megaspinosa indicated that the tick species may have been introduced with the sika deer. Furthermore, H. megaspinosa larvae were more abundant at collection sites 21–40 days after sika deer were caught by foot snare traps indicate that engorged female of this tick species were forced to drop off in a very limited area near the foot snare trap. This represented a risk for hunters and people associated with wildlife control visiting the area.

© 2020 The Author(s). Objectives: Following the massive earthquake that struck eastern Japan on March 11, 2011, a large amount of radioactive material was released into the environment from the damaged reactor of the Fukushima Daiichi Nuclear Power Plant (FDNPP). After the FDNPP accident, radiocaesium was first detected in muscle samples from wild Japanese monkeys exposed to radioactive materials, and haematologic effects, changes in head size, and delayed body weight gain were also reported, but little is known about the distribution of 137Cs in the organs and tissues of wild Japanese monkeys. Results: We detected the 137Cs in various organ and tissue samples of 10 wild Japanese monkeys inhabiting the forested areas of Fukushima City that were captured between July and August 2012. Among muscle, brain, heart, kidney, liver, lung, and spleen, muscle exhibited the highest and the brain the lowest 137Cs concentration. The concentration (mean ± SD) of 137Cs in muscle, brain, heart, kidney, liver, lung, and spleen was 77 ± 66, 26 ± 22, 41 ± 35, 49 ± 41, 41 ± 38, 53 ± 41, and 53 ± 51 Bq/kg, respectively. These results can help us understand the biological effects of long-term internal radiation exposure in non-human primates.

© 2020 The Japanese Society of Veterinary Science. We analyzed the genotypes of three pregnant females and their litters to investigate the phenomenon of multiple paternity in wild raccoon dogs (Nyctereutes procyonoides) using 17 microsatellite markers. If a female has mated with only one male during estrus, then the maximum number of paternal alleles will not exceed two among littermates with the same father. The results revealed two out of three litters had three or four paternal alleles at one or five microsatellite loci. Therefore, the female had mated with more than one male during estrus. To the best of our knowledge, the present study is the first to report the possibility of multiple paternity in wild raccoon dogs.

© 2019 Tanaka, Saeki, Hayama and Kass. Animal-related consequences were not anticipated in disaster preparedness planning in Japan at the time of its massive earthquakes in 2011. Evacuation failure was quite common due to pet ownership in this disaster. Public attention to the welfare of affected animals in this disaster triggered an awareness of the importance of caring for their needs. However, research on human behavior toward pets or effect of pets on human during disasters remains sparse. In this study, post-traumatic stress disorder (PTSD) scores among pet-owners and non-pet owners in Japan's 2011 earthquake disaster were compared, and attitudes toward pets were evaluated. A questionnaire was distributed to attendees, and interviews were performed at an annual animal welfare event. The Japanese-language version of the revised Impact of Event Scale was used to evaluate PTSD from the disaster. PTSD scores were higher in pet-owners compared to non-pet owners immediately after the earthquakes, but were lower in pet-owners compared to non-pet owners 4.4 years following the disaster. Most people opined that pets should evacuate with people, although less than half of non-pet owners agreed with having animals co-located at evacuation centers. In order to enhance safety and security of both humans and animals at evacuation centers, it is important to proactively address animal issues in disaster preparedness planning. Although pets were regarded by some as adverse risk factors for human health and safety during a disaster; this study instead suggests that pets may play an important positive and protective role for disaster victims.

© 2019 The Japanese Society of Veterinary Science. A 21-year-old male masked palm civet died after 2 months of continuous abdominal distention and poor appetite. Grossly, both musk glands were markedly swelled. Microscopically, round, polygonal and spindle neoplastic cells proliferated diffusely in the right musk gland and a metastatic focus was observed in the lung. The neoplastic cells had abundant cytoplasm with faintly eosinophilic inclusions that ultrastructurally corresponded to whorl aggregates of intermediate filaments. Immunohistochemically, these cells were positive for vimentin, cytokeratins and glial fibrillary acidic protein and negative for desmin. Based on these findings, the tumor was diagnosed as malignant rhabdoid tumor. Papillary adenoma was seen in the opposite musk gland. T-cell lymphoma of the lymph nodes, small intestine and liver was considered as the cause of death.

© 2018 Since the raccoon (Procyon lotor) was introduced to Japan, studies have established that they are infested with native Japanese tick species. However, the quantity of ticks infesting raccoons is unknown. We conducted a survey of ticks on invasive raccoons captured on the Miura Peninsula, Kanagawa Prefecture, Japan, from April 2015 through June 2016 to determine the species of ticks and to quantify the intensity of tick infestation in order to obtain basal information related to the ecology of host–parasite relationships among indigenous tick species and an alien mammalian species. We collected and identified 15,931 ticks of two genera and six species, namely, Haemaphysalis flava, H. megaspinosa, H. longicornis, H. japonica, Ixodes ovatus, and I. tanuki, from 100 out of 115 raccoons. The dominant tick species was H. flava (96.8%) and individuals were mainly adults. Seasonal patterns of infestation intensity of adults and nymphs peaked in the autumn and winter and decreasing in the late spring and summer, May to August, while larvae peaked in August. Our results indicated that host–parasite relationships between invasive raccoons and Japanese tick species, especially H. flava, were established in Kanagawa Prefecture. The ticks infest invasive raccoons for their blood-meal and also for overwintering. The results of this study extend our understanding of the ecology of tick-borne diseases.

© 2018 The Japanese Society of Veterinary Science. To examine outbreaks of mange in raccoon dogs (Nyctereutes procyonoides) with respect to population density, we analyzed camera trap videos, and isolated mites from raccoon dog carcasses. In a camera trapping survey, we categorized the skin condition of raccoon dogs, and used a number of independent videos to calculate the relative abundance index (RAI). The RAI of raccoon dogs with alopecia increased following an increase in the RAI of those without alopecia. Among 27 raccoon dog carcasses, 12 showed mange-compatible skin lesions. Sarcoptes scabiei was isolated from 11 of these raccoon dogs, indicating that sarcoptic mange was endemic in our study area. Therefore, a high relative population density may be a factor underlying epizootics of sarcoptic mange in raccoon dogs.

© The Author(s) 2017. To evaluate the biological effect of the Fukushima Daiichi nuclear disaster, relative differences in the growth of wild Japanese monkeys (Macaca fuscata) were measured before and after the disaster of 2011 in Fukushima City, which is approximately 70 km from the nuclear power plant, by performing external measurements on fetuses collected from 2008 to 2016. Comparing the relative growth of 31 fetuses conceived prior to the disaster and 31 fetuses conceived after the disaster in terms of body weight and head size (product of the occipital frontal diameter and biparietal diameter) to crown-rump length ratio revealed that body weight growth rate and proportional head size were significantly lower in fetuses conceived after the disaster. No significant difference was observed in nutritional indicators for the fetuses' mothers. Accordingly, radiation exposure could be one factor contributed to the observed growth delay in this study.

© 2017, The Author(s). During grooming, primates remove harmful ectoparasites, such as ticks and lice, and there is direct evidence for a health benefit of tick removal. Grooming behaviors differ among primates with respect to age and sex. Moreover, the number of ectoparasite may exhibit seasonal variation. Therefore the number of ectoparasites on a host may vary with effects, host age and sex, and season. However, these effects have not been a focus of louse infestation studies of primates. Grooming in Japanese macaques is related to sex and age, with developmental changes in behavior corresponding to the timing of tooth eruption. Moreover, behavioral data for Japanese macaques suggest that lice load may differ with the season. Thus, we examined whether the number of louse eggs varies according to host macaque sex, age, and season, and whether it changes in response to tooth eruption. We counted unhatched and hatched eggs attached to the hair on six 1-cm2 areas on the left wrist skin of culled macaques, using a stereoscopic microscope. We sampled five winter coats and three summer coats for each age class: infant, juvenile, adolescent, and adult. The number of unhatched and hatched eggs was related to age, but not to sex and season. There were significant differences in the number of unhatched eggs between infants and adults, juveniles and adults, and adolescents and adults. There were also significant differences in the number of hatched eggs between infants and adults, juveniles and adults, adolescents and adults. Tooth eruption did not influence the number of louse eggs. These results suggest that researchers should consider the age of host animals when assessing the relationship between grooming and ectoparasites.

A helminthological survey on the Japanese macaques (Macaca fuscata) captures in Fukushima-shi, Fukushima Prefecture, Japan, between April, 2012 and April, 2013, was performed, and comparison with the data from the macaque individuals captured in almost same period in the Shimokita Peninsula, Aomori Prefecture was done. Among 100 macaque individuals, 5 helminth species, namely, Ogmocotyle ailuri, Bertiella studeri, Trichuris sp., Oesophagostomun aculeatum and Strongyloides fuelleborni, were obtained. Especially, T. sp. is almost common species in the macaque individuals examined as well as the peninsula. It could be regarded as agents of zoonotic helminthiasis, the occurrence should be cautious. B. studeri and O. aculeatum were obtained from the present macaques, although the both species were not obtained in the peninsula. Adding to the geographical comparison, statistical analysis of relationships between the occurrence/incidence of the parasitic helminths and host age/sex or season among the present individuals were performed.

© 2017 Tanaka et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The Great East Japan Earthquakes of March 11, 2011 caused immense harm to the community and subsequent nuclear accident in Fukushima Prefecture extended the damage. Local residents were forced to evacuated without pets and the left behind animals were rescued from the restricted zone one month later. Unplanned animal rescue and unregulated sheltering caused secondary damage to animals such as disease epidemics at impounded animal shelter. The purpose of this study was to retrospectively evaluate the incidence of upper respiratory infection (URI) and diarrhea in cats at the first response animal shelter in Fukushima, and investigate factors affecting the duration of disease and determinants of treatments performed. Eighty percent and 59% of impounded cats developed URI, 71% and 54% of cats developed diarrhea, and 91% and 83% of cats had at least one disease in 2011 and 2012, respectively. Uses of multiple drug administration (more than five drugs) was associated with prolonged URI and diarrhea. Multiple antibiotics, antihistamines, interferon, and steroids were associated with relapse of and prolonged URI. Developing a standardized treatment protocol for commonly observed diseases at Japanese animal shelters to prevent and control diseases, to promote animal welfare, and protect public health in the face of future disasters is overdue.

<p>During the autumn migration of many waterfowls, body mass is lowest upon arrival at the wintering area and gradually increases during the winter. Consequently, body mass is highest before the spring migration. We studied the pattern of body mass changes in the Black-Headed Gull (Larus ridibundus) from December 2010 to December 2016 in the Shinhama area of Chiba, Japan. Based on 327 captured animals, body mass increased during the wintering period, but tended to decrease before migration. In 2014–2016, a muscle mass reduction in females was observed, explaining the change in body mass. However, the observed weight loss may be caused by many factors, which may be related to the migratory ecology of the regional population.</p>