Sika Deer Research Articles

Enhancing Wildlife Detection Using Thermal Imaging Drones: Designing the Flight Path

Thermal imaging drones have transformed wildlife monitoring by facilitating the efficient and noninvasive monitoring of animal populations across large areas. In this study, an optimized flight path design was developed for monitoring wildlife on Guleopdo Island, South Korea using the DJI Mavic 3T drone equipped with a thermal camera. We employed a strata-based sampling technique to reclassify topographical and land cover information, creating an optimal survey plan. Using sampling strata, key waypoints were derived, on the basis of which nine flight paths were designed to cover ~50% of the study area. The results demonstrated that an optimized flight path improved the accuracy of detecting Formosan sika deer (Cervus nippon taiouanus). Population estimates indicated at least 128 Formosan sika deer, with higher detection efficiency observed during cloudy weather. Customizing flight paths based on the habitat characteristics proved crucial for efficient monitoring. This study highlights the potential of thermal imaging drones for accurately estimating wildlife populations and supporting conservation efforts.

Effects of sika deer antler protein on immune regulation and intestinal microbiota in mice

Effects of sika deer antler protein on immune regulation and intestinal microbiota in mice

The Improvement Effects of Sika Deer Antler Protein in an Alzheimer's Disease Mouse Model via the Microbe-Gut-Brain Axis.

Alzheimer's disease (AD) is a neurodegenerative disorder of the central nervous system. The interplay between the intestinal microbiota and metabolites is believed to influence brain function and the pathogenesis of neurodegenerative conditions through the microbe-gut-brain axis. Sika deer antler protein possesses neuroprotective properties; however, the precise mechanism by which it improves AD remains unclear. Sika deer antler protein ameliorated AD invivo by activating the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway. The metabolome of brain and intestinal tissues and the microbiota of intestinal contents were tested and analyzed according to the microbe-gut-brain theory. Sika deer antler protein increased beneficial bacterial levels and decreased harmful bacterial levels. Correlation analyses using the gut flora-metabolomics pathway ultimately revealed that sika deer antler protein modulated the brain and intestinal tract bi-directionally via the tyrosine metabolism pathway, thereby establishing a connection within the microbe-gut-brain axis. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of the differential metabolite targets of the DAP4 group showed that the enriched pathways mainly included PI3K/AKT, which was consistent with the findings of the pharmacodynamic mechanisms observed in invivo experiments. This suggests that antler protein may be involved in microbe-gut-brain interactions through tyrosine metabolism and may improve AD by activating the PI3K/AKT/Nrf2 signaling pathway. These findings add to our understanding of the microbe-gut-brain axis facilitated by sika deer antler protein and offer novel insights for further research on sika deer antler protein in alleviating AD.

Vigilance levels of sika deer in nonhunting areas with moderate human activity

Vigilance levels of sika deer in nonhunting areas with moderate human activity

Морфогистологическая структура печени оленевых (Cervidae) как индикатор благополучия их популяций

Wild ungulates are a convenient object for environmental monitoring. The authors used the histological structures in deer’s liver to assess the well-being of populations in unfavorable anthropogenic and natural habitats. The research featured liver tissues of red deer (Cervus elaphus), sika deer (Cervus nippon), and fallow deer (Dama dama). The histosections were examined in a MEIJI TECHNO microscope using the Vision Bio (Epi) software. The statistical processing involved traditional methods using the correlation and one-factor analysis of variance. The null hypothesis was rejected at an ingenuity level of ≤ 0.05. The structure of the hepatic plates, blood vessels, foci of necrosis, and inflammation proved suitable as indicators. The cell count, structure, shape, ratio of mono- and binuclear hepatocytes, as well as their nuclei and cytoplasm, were assessed by microscope. The areas of cells, nuclei, and cytoplasm, as well as the value of the nuclear-cytoplasmic index, demonstrated diagnostic significance. A number of parameters depended on age and sex. The indicators demonstrated reliable correlations. The animals had a similar histological picture, even when the samples were obtained from geographically separated areas. The samples showed pathological transformations, including necrotic foci and binucleate hepatocytes. The structure and microvasculature of hepatic plates were disturbed. Well-being assessment is a relevant issue for populations of economically important animal species. An environmental monitoring system with wild ungulates as biological indicators could improve the monitoring system for the state of biota and its qualitative parameters, as well as ensure the well-being of the livestock and the high quality of the resulting products. The obtained histomorphometric parameters can be used as reference values in the norm-pathology gradient.

Spatiotemporal differences induced changes in the structure and function of the gut microbiota in an endangered ungulate

The composition and function of animal gut microbiota are shaped by various factors, among which diet is one of the major factors. Diet is affected by seasonal shifts and geographical differences, which in turn impact the host’s nutritional levels. To adapt to these environmental changes, the gut microbiome often produces matching responses. Understanding the relationships among the environment, diet, host and the gut microbiome is helpful for exploring the environmental adaptation of wildlife. Here, we chose wild sika deer (Cervus nippon), which is composed natural allopatric populations, to explore how the environment shapes the gut microbiome and affects the relationship between microbiota composition and function and the mutual adaptation of the seasonal living environment to seasonal dietary changes. To this purpose we used DNA metabarcoding, 16S RNA gene amplification sequencing, metagenomic shotgun sequencing and nutritional analyses to comprehensively examine the relationships among the forage plant, nutrient status and host gut microbiome. Our analyses showed spatiotemporal differences in diet between the Tiebu and Hunchun regions, which ultimately led to varying intakes of protein, cellulose, and soluble sugar. The microbiome composition and function showed unique characteristics in each group, and significant differences were detected at the gene level for the protein absorption and metabolism pathway, the carbohydrate metabolic absorption pathway, and cellulase enzyme function, which are related to nutrition. We also found differences in the pathogenic bacteria and resistance mechanisms genes of the gut microbiota in different groups. Our results showed that the gut microbiome of allopatric populations adapts to changes in food composition and nutrition in different seasons and areas to help the host cope with spatiotemporal changes in the living environment. At the same time, varying levels of human activity can have potential health impacts on wild animals.

Monkey-deer rodeo: exploring the mounting behaviours of Japanese macaques (Macaca fuscata) on Sika deer (Cervus nippon).

Interspecies interactions present diverse forms and functions, contributing significantly to ecological and social dynamics. This study focuses on the mounting behaviours of Japanese macaques (Macaca fuscata) towards Sika deer (Cervus nippon), a rare and still unexplained phenomenon, with minimal emphasis on the behaviour of the deer. Using video data from two distinct sites, Yakushima and Minoh, Japan, we documented 45 sequences of macaque-deer interactions and analysed macaques' behaviours and deer behaviours using focal and behavioural sampling techniques. We identified four primary activities performed by macaques during mountings-sexual, play, grooming, and resting-with resting being predominant. The study evaluates six hypotheses regarding the functions of these mounting behaviours: (1) interactions are sex-specific, (2) macaques use deer for transportation, (3) mutual warming through physical contact occurs, (4) deer provide support for resting, (5) macaques engage in grooming to consume parasites or play to strengthen interspecies bonds, and (6) aggressive signals relate to resource disputes or rejection of mounting behaviour. Statistical analyses using the Kruskal-Wallis test and Dunn's post-hoc test revealed significant differences between resting and other active behaviours, but no significant differences in behaviour duration between lying and sitting positions. Adults engaged in mounting for longer periods than juveniles, suggesting potential age-related differences in social and reproductive roles. These findings enhance our understanding of interspecies interactions by focusing on macaque behaviours and emphasise the need for longitudinal studies to clarify the ecological and social implications of these interactions.

Settlement and Acclimatization of Sika Deer in the Russian Federation

The article discusses the issues of conservation, distribution and acclimatization of sika deer on the territory of the Russian Federation, the Central Federal District and of the National Park “State Complex “Zavidovo”. A detailed analysis of the condition of the first range of sika deer in the Primorsky Krai, as well as the history of settlement and dynamics of its population in the Russian Federation. For the regions of the Central Federal District, the results of the cadastral assessment of sika deer resources were calculated, including the average long-term week, the average long-term illumination of the population (animals) per 1000 hectares of characteristic lands and the average long-term cost of resources (million rubles). As an effective model for the acclimatization of sika deer, an experience of its economic use was carried out in the National Park “State сomplex “Zavidovo” (Tver region).

Developing an Alert System for Agricultural Protection: Sika Deer Detection Using Raspberry Pi

Agricultural loss due to the overpopulation of Sika deer poses a significant challenge in Japan, leading to frequent human–wildlife conflicts. We conducted a study in Muroran, Hokkaido (42°22′56.1″ N–141°01′51.5″ E), with the objective of monitoring Sika deer and notifying farmers and locals. We deployed a Sika deer detection model (YOLOv8-nano) on a Raspberry Pi, integrated with an infrared camera that captured images only when a PIR sensor was triggered. To further understand the timing of Sika deer visits and potential correlations with environmental temperature and humidity, respective sensors were installed on Raspberry Pi and the data were analyzed using an ANOVA test. In addition, a buzzer was deployed to deter Sika deer from the study area. The buzzer was deactivated in the first 10 days after deployment and was activated in the following 20 days. The Sika deer detection model demonstrated excellent performance, with precision and recall values approaching 1, and a bounding box creation latency of 0.82 frames per second. Once a bounding box was established after Sika deer detection, alert notifications were automatically sent via email and the LINE messaging application, with an average notification time of 0.32 s. Regarding the buzzer’s impact on Sika deer, 35% of the detected individuals reacted by standing upright with alert ears, while 65% immediately fled the area. Analysis revealed that the time of day for Sika deer visits was significantly correlated with humidity (F = 8.95, p < 0.05), but no significant association with temperature (F = 0.681, p > 0.05). These findings represent a significant step toward mitigating human–wildlife conflicts and reducing agricultural production losses through effective conservation measures.

Characteristics of Meat from Farmed Sika Deer (Cervus nippon) and the Effects of Age and Sex on Meat Quality.

This study assessed the meat quality of Sika deer (Cervus nippon) from various age and sex groups using the longissimus dorsi (LD) muscle. Samples from different age groups (2, 3, and 4 years old) were analyzed for various parameters. The results show that, with increasing age, there is a decrease in moisture and drip loss (p < 0.05), alongside increases in ash, protein, fat, and cooking loss (p < 0.05). Female deer showed an increase in tenderness (p < 0.05), whereas males generally had a higher amino acid content (p < 0.05). Interestingly, 2-year-old female Sika deer had more saturated fatty acids (p < 0.05), while 3- and 4-year-old females had more unsaturated fatty acids compared to age-matched males (p < 0.05). Notably, 3-year-olds had higher levels of monounsaturated and polyunsaturated fatty acids in both the male and female groups (p < 0.05). Overall, this study provides the first comprehensive evidence that Sika deer meat is a nutritious source of lean protein. Notably, meat from 3-year-old Sika deer, regardless of sex, contains higher nutrient levels and is more tender compared to meat from deer of other ages. Additionally, meat from females tends to be more tender than that from males.

Characteristics of Cerebrovascular Response to Intrinsic Vasoactive Substances in Sika Deer (Cervus nippon yesoensis) and the Possible Effects of Gravity on Adrenergic Responses.

Gravity may exert species-specific effects on quadrupedal vasoreactivity, reflecting variations in the vertical displacement of the cardiocranial axis from the dorsal plane. Deer show markedly displaced cardiocranial axes compared to their closest phylogenetic relatives, but their relative cerebrovascular responses remain unelucidated. Accordingly, we investigated the responses to noradrenaline (NA), acetylcholine (ACh), 5-hydroxytryptamine (5-HT), histamine, angiotensin (Ang) II, and bradykinin (BK) in cervine basilar arterial rings. NA and 5-HT induced slight contraction, and ACh induced relaxation, which contrasts with the findings reported in pigs and cattle. The cumulative response to ACh was abolished by endothelial denudation and inhibited by Nω-nitro-L-arginine (a nitric oxide synthase inhibitor), atropine (a nonselective muscarinic antagonist), and p-fluoro-hexahydro-sila-difenidol (an M3 antagonist). Pirenzepine (an M1 antagonist) and methoctramine (an M2 antagonist) showed no significant effects. Histamine induced contractions, with its concentration-response curve shifted to the right in parallel by diphenhydramine (an H1 antagonist). However, cimetidine (an H2 antagonist) showed no significant effects. Ang II and BK had no vasomotive effects. NA and ACh induced different cerebrovascular responses in sika deer versus cattle, but histamine and BK did not. Our findings suggest that cerebrovascular responses are influenced by the similarity of animal species and the head and heart positions relative to gravity.

Unveiling Group Dynamics and Habitat Utilization Patterns of Invasive Sika Deer (Cervus nippon) in Jeju Island, South Korea: Insights from Camera Trapping Analysis

Unveiling Group Dynamics and Habitat Utilization Patterns of Invasive Sika Deer (Cervus nippon) in Jeju Island, South Korea: Insights from Camera Trapping Analysis

Cameras or Camus? Comparing Snow Track Surveys and Camera Traps to Estimate Densities of Unmarked Wildlife Populations

ABSTRACTPopulation density is a valuable metric used to manage wildlife populations. In the Russian Far East, managers use the Formozov‐ Malyushev‐Pereleshin (FMP) snow tracking method to estimate densities of ungulates for hunting management. The FMP also informs Amur tiger (Panthera tigris altaica) conservation since estimates of prey density and biomass help inform conservation interventions. Yet, climate change and challenges with survey design call into question the reliability of the FMP. Camera traps offer a promising alternative, but they remain unexplored for monitoring tiger prey density. Over three years (2020‐2022), we used the FMP and camera‐based methods to estimate densities of four prey species of the Amur tiger in the Sikhote‐ Alin Biosphere Reserve, Russian Far East: wild boar (Sus scrofa), red deer (Cervus canadensis), roe deer (Capreolus pygargus), and sika deer (Cervus nippon). We compared FMP results from snow track survey routes either along trails, or along routes representative of the study area, and estimates derived from camera data using the random encounter model (REM), space‐to‐event model (STE), and time‐to‐event model (TTE). We found that density estimates from representative routes were typically lower than routes along trails and indicated different relative densities of prey. Density estimates from camera traps and representative track surveys were generally similar with no significant relative bias, but precision was poor for all methods. Differences between estimates were amplified when converted to prey biomass, particularly with larger, more abundant prey, which poses a challenge for their utility for tiger managers. We conclude camera traps can offer an alternative to snow track surveys when monitoring unmarked prey, but we caution that they require considerably more resources to implement. Tiger managers should be especially cautious when extrapolating density to estimates of prey biomass, and we encourage future research to develop more robust methods for doing so.

Cervus nippon antler inhibits hormone disorder induced mammary gland hyperplasia by regulating the cell cycle

Cervus nippon antler inhibits hormone disorder induced mammary gland hyperplasia by regulating the cell cycle

Influence of the Introduction of Sika Deer on the Current State of the Number and Distribution of Ungulate Mammals in the Ussuriysky Nature Reserve (Russian Far East)

Influence of the Introduction of Sika Deer on the Current State of the Number and Distribution of Ungulate Mammals in the Ussuriysky Nature Reserve (Russian Far East)

Artificial intelligence-aided electrochemical sensors for capturing and analyzing fingerprint profiles of medicinal materials

This study explores the application of artificial intelligence-aided electrochemical sensors for authenticating medicinal materials, focusing on sika deer antler cap powder. Utilizing differential pulse voltammetry and graphene-modified screen-printed electrodes, we developed a novel method to capture unique electrochemical fingerprints of authentic, counterfeit, and adulterated samples. Three machine learning models—Support Vector Machine (SVM), Random Forest (RF), and Extreme Learning Machine (ELM)—were evaluated using both full voltammogram and principal component analysis (PCA) reduced features. The SVM model with PCA-reduced features emerged as the optimal approach, achieving a classification accuracy of 97.9 % while reducing training time by 65.6 % (from 3.2 s to 1.1 s) and prediction time by 71.4 % (from 0.07 s to 0.02 s per sample) compared to using full voltammogram features. This reduction in computational complexity was achieved by decreasing the input dimensionality from 601 to 5 features through PCA, while maintaining high classification performance across all sample categories. This model demonstrated high sensitivity (>97 %) and specificity (>98 %) across all sample categories, with a notably low limit of detection for adulteration at 2.8 %. Characteristic peaks, such as the pantocrin peak at 0.25 V for authentic samples, provided a robust basis for differentiation. The method's effectiveness in detecting subtle adulterations was evidenced by its ability to identify samples with as low as 5 % adulteration. Furthermore, the approach showed excellent generalization, maintaining 97.0 % accuracy on an independent validation set. These findings highlight the potential of this technique for rapid, accurate, and cost-effective authentication of medicinal materials, addressing the growing challenge of counterfeit products in the pharmaceutical industry.

Settlement and Acclimatization of Sika Deer in the Russian Federation

Settlement and Acclimatization of Sika Deer in the Russian Federation

Nutritional Processing Quality of Sika Deer (Cervus nippon) Venison in Different Muscles.

In order to investigate the nutritional processing quality of sika deer (Cervus nippon) venison at different sites, the pH24 h, tenderness, pressurized water loss rate, meat color, intramuscular fat, moisture, protein, amino acid, fatty acid and squalene contents of sika deer venison were determined in twelve sites: foreleg, hind leg, outer tenderloin, rump, neck meat, chest meat, deer flank, abdominal rib, high rib, tenderloin, anterior tendon and posterior tendon. The results showed that the pH24 h of sika deer venison at different sites was 5.49~5.78; the tenderness of outer tenderloin (31.71 N) was the lowest, and the neck meat (68.53 N) was the highest; the squeezing moisture of tenderloin (28.12%) was the largest, and the foreleg (12.34%) was the smallest; the brightness of outer tenderloin L* (29.68) was the lowest, and the redness a* and yellowness b* of deer flank were the highest; the intramuscular fat and moisture were 0.66~4.97% and 71.00~73.78%, respectively; and the protein content of outer tenderloin (23.44%) and rump (24.02%) was high. The venison meat contained 17 kinds of amino acids, and the total amount was 63.87~79.33 g/100 g. It was rich in essential amino acids, mainly lysine and leucine, accounting for 64.29~65.39% of non-essential amino acids, which was close to the ideal protein composition. Palmitoleic acid and oleic acid were the main monounsaturated fatty acids in venison, and the contents of abdominal ribs were the highest, 16,875.33 mg/kg and 31,772.73 mg/kg, respectively. The contents of essential fatty acids were also the highest in abdominal ribs (11,225.37 mg/kg); forelegs, hind legs, outer tenderloins, rumps, neck meat, chest meat, high rib, tenderloins, anterior tendons and posterior tendons were all good sources of polyunsaturated fatty acids. Squalene content was highest in the abdominal rib (100.85 mg/kg). The nutritional processing quality of sika deer venison in different muscles is significantly different, and this study can provide a data basis for the evaluation and processing of sika deer venison quality.

Seasonal infestation patterns of ticks on Hokkaido sika deer (Cervus nippon yesoensis).

Ticks prefer specific feeding sites on a host that are influenced by host–tick and tick–tick interactions. This study focused on the spatiotemporal distribution of ticks in Hokkaido sika deer, an important tick host in Hokkaido, Japan. Tick sampling was performed on the sika deer in the Shiretoko National Park between June and October 2022. Ticks were collected from 9 different body parts of the deer to compare their attachment site preferences. Interspecific and intraspecific relationships among ticks were examined using co-occurrence analysis. The collected ticks were nymphal and adult stages of 4 species: Ixodes ovatus, Ixodes persulcatus, Haemaphysalis japonica and Haemaphysalis megaspinosa. Seasonal variations in tick burden were observed, with I. persulcatus and I. ovatus peaking in June and declining towards October; H. japonica showing low numbers in July and August and increasing from September; and H. megaspinosa appearing from September onwards with little variation. Attachment site preferences varied among species, with a significant preference for the pinna in I. ovatus and I. persulcatus. Haemaphysalis japonica was mainly found on the body and legs between June and August, and shifted to the pinna from September. Haemaphysalis megaspinosa showed a general preference for areas other than the legs. Co-occurrence analysis revealed positive, negative and random co-occurrence patterns among the tick species. Ticks of the same genus and species exhibited positive co-occurrence patterns; I. ovatus showed negative co-occurrence patterns with Haemaphysalis spp. This study revealed the unique attachment site preferences and distinct seasonal distributions of tick species in the Hokkaido sika deer.

High-quality sika deer omics data and integrative analysis reveal genic and cellular regulation of antler regeneration.

Antler is the only organ that can fully regenerate annually in mammals. However, the regulatory pattern and mechanism of gene expression and cell differentiation during this process remain largely unknown. Here, we obtain comprehensive assembly and gene annotation of the sika deer (Cervus nippon) genome. Together with large-scale chromatin accessibility and gene expression data, we construct gene regulatory networks involved in antler regeneration, identifying four transcription factors, MYC, KLF4, NFE2L2, and JDP2 with high regulatory activity across whole regeneration process. Comparative studies and luciferase reporter assay suggest the MYC expression driven by a cervid-specific regulatory element might be important for antler regenerative ability. We further develop a model called cTOP which integrates single-cell data with bulk regulatory networks and find PRDM1, FOSL1, BACH1, and NFATC1 as potential pivotal factors in antler stem cell activation and osteogenic differentiation. Additionally, we uncover interactions within and between cell programs and pathways during the regeneration process. These findings provide insights into the gene and cell regulatory mechanisms of antler regeneration, particularly in stem cell activation and differentiation.