Shin-Ichi Hayama

Nippon Veterinary and Life Science University | NVLU · School of Veterinary Medicine

In April 2012 we carried out a 1-year hematological study on a population of wild Japanese monkeys inhabiting the forest area of Fukushima City. This area is located 70 km from the Fukushima Daiichi Nuclear Power Plant (NPP), which released a large amount of radioactive material into the environment following the Great East Japan Earthquake of 2011...

Following the massive earthquake that struck eastern Japan on March 11, 2011, a nuclear reactor core meltdown occurred at the Fukushima Daiichi Nuclear Power Plant, operated by Tokyo Electric Power Company, and was followed by the release of large amounts of radioactive materials. The objective of this study was to measure the concentration of radi...

Macroscopic and histological changes were examined on the female reproductive organs of Japanese monkeys (Macaca fuscata) with varying reproductive status in enclosed and provisioned troops. The weight and size of reproductive organs are described. The size of uterus declined in 2–3 months after parturition. The number of parturition was roughly es...

This study is the first to determine the conception dates of specific individuals and estimate the pregnancy rate of a wild population in Japanese monkeys. The conception dates estimated from the embryonic ages of 37 fetuses were distributed over 128 days between September 17 and January 23, with a mean conception date of November 19 (SD=29.2 days)...

In this study, based on the data from FIV screening surveys of captive cats conducted by the Kyushu Veterinary Union and collaborators as part of the infection control program for Tsushima leopard cats (Prionailurus bengalensis euptilurus), we elucidated the spatial distribution of FIV-positive individuals among leopard cats and domestic cats using...

We aimed to investigate the surveillance system and control measures against highly pathogenic avian influenza (HPAI) in captive and rescued wild birds. We administered questionnaires and an interview survey to employees of zoos, aquariums, wildlife rescue centers, and the animal welfare and management divisions of local governments (mainly prefect...

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 202...

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...

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 (Caprico...

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...

Microplastics (MPs) have been found in a wide range of animal species including humans. The detection of MPs in human lungs suggests that humans inhale airborne microplastics (AMPs). Although birds respire more efficiently than mammals and are therefore more susceptible to air pollution, little is known about their inhalation exposure to MPs. In th...

An engorged ixodid tick was collected from a rescued short-tailed shearwater, Puffinus tenuirostris (Temminck), at Funabashi Sanbanse Seaside Park in Chiba Prefecture, Japan. Based on morphological features, we identified the specimen as Ixodes kerguelenensis (André and Colas-Belcour), which is a species known to infest seabirds in Oceania. To our...

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 J...

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...

The biological effects of lead (Pb) contamination have been reported in various species. There are no restrictions on the use of Pb products, including bullets, in the areas south of Hokkaido, Japan. Local governments have announced the presence of Pb in the soil sediments of water bodies. Previous studies have confirmed the relationship between bl...

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...

We examined the clinical signs and necropsy findings of a mountain hawk-eagle (Nisaetus nipalensis) that died during rehabilitation. The bird was rescued and treated for open fracture of the right forearm. During rehabilitation, the bird could not stand up or fly. Part of the right secondary and left and right primary feathers were removed during r...

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 dog...

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...

The biological effects of lead (Pb) contamination have been reported in various species. There are no restrictions on the use of Pb products, including bullets, in the areas south of Hokkaido, Japan. Local governments have announced the presence of some Pb in the soil sediments of water bodies. Previous studies have confirmed the relationship betwe...

Rescued wild birds can provide useful information regarding the identity of individuals, as well as the causes of any injuries. We examined one Ural Owl Strix uralensis (Strigidae) rescued in Kusatsu City, Shiga Prefecture, in April 2020. Macroscopic examination of the owl’s beak and claws revealed that the owl had been previously managed. From evi...

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 spec...

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 Japan...

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...

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...

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.

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 ma...

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 oth...

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 his...

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 collecte...

Animal welfare is an important element of wildlife rehabilitation, and some countries use standardized protocols to ensure animal welfare is addressed during the rehabilitation process. In Japan (where the term “wildlife rescue” is preferred), no common management procedures prioritize animal welfare, especially for wild bird rescue. Approximately...

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 expo...

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 o...

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 r...

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’...

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...

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 (Chroicocephal...

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 8,348 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...

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...

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 expose...

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 expose...

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 abunda...

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...

https://www.frontiersin.org/10.3389/conf.fvets.2019.05.00024/6796/GeoVet_2019_Novel_spatio-temporal_approaches_in_the_era_of_Big_Data/all_events/event_abstract

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 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...

The Tsushima leopard cat, most endagered in Japan, have been exposed to the threat of disease from feral domestic cats, sach as feline immunodeficiency virus (FIV) and feline louchemia vrus (FeLV). Based on the data from FIV and FeLV screening surveys, and the population densities of leopard cats and domestic cats, we performed geographical infecti...

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 ef...

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...

In recent years, the wild animal issues became serious, and many related laws and regulations have been revised. In particular, as the number of deer and wild boars population increased, it became uncontrollable, so in 2014 the birds and animal protection law was revised and private enterprises and others were able to enter the capture project. How...

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...

In order to establish the minimum adverse effect of the sex identification method in birds, the droppings of 11 orders of 42 species of Japanese birds were collected for DNA analysis. The chromosomes used for sex identification were the protein-encoding spindlin gene (SPIN), presumptive pseudogene (EE0.6), and chromo helicase DNA-binding gene (CHD)...

Heart rate (HR) and heart rate variability (HRV) provide non- invasive measures of the relative activity of the parasympathetic nervous system (PNS), which promotes self-maintenance and restoration, and the sympathetic nervous system (SNS), which prepares an animal for danger. The PNS decreases HR, whereas the SNS increases HR. The PNS and SNS also...

Now in its 30th anniversary in 2014 wildlife science is creating, also Japanese Society of Zoo and Wildlife Medicine at the same time becomes a founding 20 anniversary. Wildlife science, for the purpose of co-existence between humans and wildlife, is an academic who has evolved while integrating the area concerned. During this time, disciplines tha...

Feral raccoons (Procyon lotor) have been growing in number in Japan, and they are becoming a problematic invasive species. Consequently, they are commonly captured and killed in pest control programs. For effective population control of feral raccoons, it is necessary to understand their reproductive physiology and ecology. Although the reproductiv...

The Kuril harbour seal Phoca vitulina stejnegeri is an endangered species which in - habits southeastern Hokkaido, Japan. Its population declined precipitously from between 1500 and 4800 individuals in the 1940s to a few hundred individuals in the early 1970s. The causes of this decline are thought to be commercial harvesting, bycatch in autumn set...

Due to the long parturition period of raccoons, we assumed that age at first conception of late born females was later than that of early born females. From March 2005 to September 2008, 201 females estimated to be younger than 24 months were separated into early- and late-born groups on the basis of their estimated birth month (to the nearest 2 mo...

We examined the use of external measurements and relative fat deposition of adult feral raccoons (Procyon lotor) to develop relative indices of body fat deposition in post-growth feral raccoons. From March 2006 to March 2010, 288 adult raccoon carcasses (110 males, 178 females) collected in Kanagawa Prefecture, Japan, which were determined to be 24...

To estimate the public and animal health risk that alien species pose, the prevalence of Salmonella, Yersinia, and Campylobacter spp. in feral raccoons (Procyon lotor, n=459) and masked palm civets (Paguma larvata, n=153), which are abundant alien species in Japan, was investigated in urban and suburban areas of Japan. Salmonella enterica was detec...

The cadmium (Cd) content in the kidneys and livers of wild birds was compared after classification based on the type of migration and the breeding area. A high Cd content was detected in the organs of Pacific loons breeding in North America, but these birds were thought to have been affected by oil contamination. The Cd content of organs from spotb...

Changes in body mass of a pair of captive Japanese Rock Ptarmigan Lagopus mutus japonicus and their chicks were measured using an automatic weighing system at Omachi Alpine Museum from 13 January 1995 to 29 October 1996. The male's body mass decreased gradually in late April, the beginning of the breeding season, but returned to the normal level in...

Reproduction of the masked palm civet (Paguma larvata) has not been well investigated in Japan. We examined 361 female masked palm civets harvested as nuisance animals between April 2007 and March 2009 in Kanagawa Prefecture and Tokyo Metropolis. Pregnant animals and placental scars-bearing animals were found only in 12 months old and over. In thes...

We investigated indices of fat deposition in wild Tsushima leopard cats ( Prionailurus bengalensis euptilurus) to establish a standard for assessing nutritional status. We used the external measurements of 101 Tsushima leopard cats captured for research purposes and those sheltered due to injury and other reasons between 1985 and 2007. These extern...

The cadmium (Cd) content in the kidneys and livers of wild birds was compared after classification based on the type of migration and the breeding area. A high Cd content was detected in the organs of Pacific loons breeding in North America, but these birds were thought to have been affected by oil contamination. The Cd content of organs from spotb...

In order to examine reproductive characteristics of feral raccoons in Kamakura, 335 raccoons were collected from March 2005 to March 2007. Raccoons were classified into five age classes: Class I, less than 5 months old; Class II, 5-11 months; Class III, 12-17 months; Class IV, 18-23 months; and Class V, over 23 months old. Females were examined for...