田中 亜紀

We examined the conception rate of wild Japanese monkeys (Macaca fuscata) in Fukushima City that were exposed to radiation as a result of the Fukushima Daiichi Nuclear Power Plant accident in March 2011. The conception rate in the year of delivery from 2009 to 2022 was estimated by dissecting individuals that were euthanized by the government for population control as a countermeasure against crop damage. To evaluate the effects of exposure, the cumulative exposure dose for each individual was calculated using the concentration of radiocesium deposited in the soil at the capture site and the concentration of radiocesium in muscle estimated from the aggregated transfer factor. There were no significant differences in conception rates across all age classes over time. In terms of conception rates by age class, there was a significant decrease post-exposure compared with pre-exposure in the age class ≥ 8 years, but no significant differences in the age class 5-7 years. The non-ovulation rate did not significantly differ between the pre- and post-exposure periods for any age class. Body fat index, which can affect fertility, was compared between the pre- and post-exposure periods, and no significant differences were found in either age class. In contrast, the median total cumulative exposure (cumulative internal exposure + cumulative external exposure) was significantly higher in the age class ≥ 8 years compared with the age class 5-7 years. These results suggest that the total cumulative exposure dose may be one of the reasons for the lower conception rate in the post-exposure period among the age class ≥ 8 years.

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 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 (T_ag: 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.

Canine leptospirosis was suspected in 11 dogs in Osaka Prefecture, Japan and 9 dogs died within a month, from October 12 to November 10, 2017. Eight of the dogs had been taken on walks along the same riverbed and 4 dogs lived in the same town. Logistic regression analysis between a comparative group and the incident cases group showed that the odds of leptospirosis infection was 13.3 times higher (<italic>p</italic> = 0.044) in the dogs taken on walks along the riverbed than in the dogs not being walked along the riverbed. It is suggesting that these walks had been a risk factor. Microscopic agglutination tests showed that antibody titers against <italic>Leptospira interrogans</italic> serovar Australis were 1:2,560 and 1:10,240 in 2 dogs. Therefore, <italic>L. interrogans</italic> serovar Australis was suspected to be the causative agent, for which no canine vaccine is available in Japan. These results suggested that <italic>L. interrogan</italic>s serovar Australis can cause local outbreaks. The development of a canine vaccine against various serotypes might help reduce local infections. Leptospirosis is an important infectious disease of dogs and it is also a zoonotic disease.

Abstract Background Hyperadrenocorticism (HAC) is a common endocrine disorder in dogs; however, there are no reports on the use of the corticotropin‐releasing hormone test (CRHT) to differentiate between pituitary‐dependent hyperadrenocorticism (PDH) and cortisol‐producing adrenal tumors (CPATs), both causative of HAC. Objectives To evaluate the usefulness of CRHT as a tool to differentiate between PDH and CPAT in dogs and to determine the reference intervals for CRHT in healthy, PDH, and CPAT dogs. Animals Dogs diagnosed with PDH (n = 21), CPAT (n = 6), and healthy beagle dogs (n = 33). Methods This prospective study included dogs with a definitive diagnosis of PDH and CPAT and healthy beagle dogs, in which CRHT was performed, were prospectively evaluated. We investigated the correlations of CRHT (endogenous adrenocorticotropic hormone [ACTH] concentration, endogenous ACTH concentration [EAC], and poststimulation ACTH concentration [PAC]) with pituitary‐to‐brain ratio (PBR) (in PDH) and with indices of adrenal ultrasonography (smaller and larger adrenal gland dorsoventral thickness in PDH and CPAT). Results For EAC, the area under the curve (AUC) was 0.95, with a cutoff value of 26.3 pg/mL (sensitivity: 90.62%, specificity: 87.50%). The AUC for PAC was 0.96 with a cutoff value of 54.5 pg/mL (sensitivity: 100.00%, specificity: 66.67%). The 95% reference interval for CRHT in healthy (control) dogs ranged 5.00 to 79.8 pg/mL (1.10‐17.57 pmol/L) for EAC, and 1.92 to 153.42 pg/mL (0.42‐33.78 pmol/L) for PAC. There was no significant correlation between PBR and CRHT, nor adrenal size and CRHT. Conclusions and Clinical Importance CRHT appears to be a rapid and reliable test for differentiating PDH from CPAT in dogs.

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.

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.

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.

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.

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.

The aims of this research were to report characteristics of rescued cats at a secondary emergency animal shelter in Fukushima prefecture, Japan, and evaluate how adoptability, stress level, upper respiratory infection (URI) syndrome incidence, and URI pathogen prevalence were associated with the cat's shelter intake source and shelter characteristics. All cats admitted to the Miharu shelter, Fukushima Prefecture from 2012 to 2014 were included in the study. The results demonstrate that in situ corticosteroid and antibiotic use were associated with cats subsequently developing upper respiratory infections (URI). Disease and cat behavior were unassociated with adoption. Cats in group housing had lower stress metrics than cats individually housed. Prevalences of URI pathogens exceeded 80%, but symptomatic cats were uncommon. Environmental enrichment and stress reduction strategies are important in controlling URI and reducing the need for corticosteroids and antibiotics in shelters. Preemptive protocols are important in preventing shelter admission of cats during disasters. (C) 2017 Elsevier B.V. All rights reserved.

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.

Objective-To identify associations among change in body weight, behavioral stress score, food intake score, and development of upper respiratory tract infection (URI) among cats admitted to an animal shelter. Design-Prospective cohort study. Animals-60 adult cats admitted to an animal shelter. Procedures-Body weight was measured on days 0 (intake), 7, 14, and 21. Behavioral stress and food intake were scored daily for the first 7 days; cats were monitored daily for URI. Results-49 of the 60 (82%) cats lost weight during at least 1 week while in the shelter. Fifteen (25%) cats lost &gt;= 10% of their body weight while in the shelter. Thirty-five of the 60 (58%) cats developed URI prior to exiting the shelter, and only 4 cats remained at least 21 days without developing URI. Cats with high stress scores during the first week were 5.6 times as likely to develop U R I as were cats with low stress scores. Food intake and stress scores were negatively correlated (r = -0.98). Conclusions and Clinical Relevance-Results indicated that cats admitted to an animal shelter were likely to lose weight while in the shelter and likely to develop URI, and that cats that had high stress scores were more likely to develop URI. (J Am Vet Med Assoc 2012;240:570-576)