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Ticks and tick-borne diseases have negative impacts on the health of wild animals including endangered and vulnerable species. The giant panda (Ailuropoda melanoleuca), a vulnerable and iconic flagship species, is threatened by tick infestation as well. Not only can ticks cause anemia and immunosuppression in the giant panda, but also bacterial and viral diseases. However, previous studies regarding tick infestation on giant pandas were limited in scope as case reports from sick or dead animals. In this study, an investigation focusing on the tick infestation of a reintroduced giant panda at the Daxiangling Reintroduction Base in Sichuan, China was conducted. Ticks were routinely collected and identified from the ears of the giant panda from March to September in 2021. A linear model was used to test the correlation between tick abundance and climate factors. All ticks were identified as Ixodes ovatus. Tick abundance was significantly different among months. Results from the linear model showed temperature positively correlated to tick abundance, while air pressure had a negative correlation with tick abundance. To the best of our knowledge, this study is the first reported investigation of tick species and abundance on a healthy giant panda living in the natural environment, and provides important information for the conservation of giant pandas and other species sharing the same habitat. [Display omitted] • Tick species and abundance from a giant panda living in the wild were systematically investigated for the first time. • Climate drivers were correlated with the Ixodes ovatus daily abundance on a giant panda living in the wild. • Ixodes ovatus abundance on a giant panda varies among months. [ABSTRACT FROM AUTHOR]

• Giant pandas cope with historical climate change via slower bioclimatic velocities. • Vigilance is needed for climate change velocity, not just the change itself. • Edge-dwelling individuals require extra attention in conservation. • Historical climate exposure serves as a proxy for adaptation assessment. Evaluating the adaptive capacity of species to past climate change is a crucial component in understanding how species respond to climatic shifts. This information serves as a vital foundation for guiding conservation practices under future environmental changes. We reconstructed the potential suitable habitat maps for giant pandas (Ailuropoda melanoleuca) during the Last Glacial Maximum (LGM, ∼22 ka) and mid-Holocene (MH, ∼6 ka) climates via an ensemble species distribution modelling approach, and compared them to the potential suitable habitats at current stage, we also estimated and compared the bioclimatic velocity of giant pandas to the climatic velocities since LGM. The results showed that the suitable habitat area for giant pandas has increased by 12.47 % from LGM to MH, and then decreased by 5.37 % from MH to current stage. The estimated climatic velocity over the suitable habitats for giant pandas was 16.00 ± 5.83 km·kyr−1 from LGM to MH and 46.13 ± 18.96 km·kyr−1 from MH to nowadays. The bioclimatic velocities for these two periods were 0.55 ± 0.55 km·kyr−1 and 8.47 ± 10.45 km·kyr−1, respectively. The result indicated that giant pandas have successfully adapted to the climate changes since LGM by migrating at a rate that lags behind the speed of climate change within their current distribution range. However, this does not imply that giant pandas possess sufficient migratory capabilities to cope with future climate crises, as the current rate of climate change exceeds that of any historical periods. [ABSTRACT FROM AUTHOR]

Abstract As certain extreme weather events are becoming frequent and intense, conservationists must identify areas across species' ranges recurrently affected, especially with regard to threatened species. Focusing on the giant panda (Ailuropoda melanoleuca) and historical flood frequency distribution, we determined overlaps between panda distribution affected by floods and nature reserves. We also examined the correspondence between areas subject to high flood exposure densities, areas with high panda habitat use, and areas that exhibit high human density. Of the 67 reserves established for giant panda conservation 7 included areas with the highest flood exposure densities while having a mean exposure ranging between 20 and 75%. In Sichuan province up to 32% of areas of high habitat use were subject to low flood density, and 10% overlapped with areas subject to high flood density. We also found that 40% of the total area with high human density was subject to a high flood density. Our findings indicate that high frequency of flooding is affecting areas of nature reserves where people are rather than areas which pandas are using more intensively. In areas occupied by pandas, strategies should remain focus on mitigating habitat degradation and fragmentation caused by human activities that can also reduce habitat resilience to floods. Management aimed at reducing vulnerability and enhancing resilience in flood-prone areas is warranted if we are to prevent negative indirect impacts on panda habitat driven by human responses to increasingly frequent and intense extreme weather events in the coming decades. Highlights • Areas inside giant panda nature reserves are highly exposed to floods. • Frequent flooding is affecting areas with people rather than areas used by pandas. • Building resilience is crutial for preventing additional pressures on panda habitat. [ABSTRACT FROM AUTHOR]

Species distribution models (SDMs) are widely used for predicting species' spatial distributions. Different model setup and data input however can lead to variable model predictions. Existing studies on quantifying SDM dissimilarity primarily rely on partitioning the variability in SDM-produced community level metrics such as species richness and turnover rate which are threshold-dependent and are generated with binary range maps of multiple species. Most existing measurements of spatial dissimilarity constitute geometric comparisons, which is limited compared to a more information-theoretic application of statistical dissimilarity measures using SDM predictions as direct input without renormalization. We introduce a novel method to quantify the degree of dissimilarity and its level of significance between unscaled SDM predictions of a single species. We apply the method to giant panda Ailuropoda melanoleuca data as well as pairs of simulated species distributions. We utilize a pixel-based Bhattacharyya distance to quantify the degree of dissimilarity among predictions of giant panda habitat of different combinations of model types, Global Climate Models (GCMs) and Representative Concentration Pathways (RCPs). Comparisons are also made between pairs of simulated species with different degrees of dissimilarity in spatial distribution. To evaluate the level of significance, the observed dissimilarity measure is compared against a null distribution that captures the level of dissimilarity caused by small and random variations. Specific pairs of climate scenarios (HadGEM2-ES with HadGEM2-AO and HadGEM2-AO with MIROC5) consistently produce statistically similar predictions of giant panda habitat; the highest level of RCP tends to result in more similar predictions, suggesting a convergence of model predictions. The simulated scenarios also show that the proposed method is able to effectively differentiate a range of artificial species with varying degree of dissimilarity in their resource selection preference. Our method can also reflect the dissimilarity that cannot be quantified by traditional metrics that rely on geometric comparisons. The proposed method supplements existing studies by utilizing a novel application of statistical comparisons to measure dissimilarity between user-defined pairs of models. It provides a robust way to construct the null distribution of dissimilarity that contrasts the degree of the observed dissimilarity with the intrinsic model variability. Our study provides useful insight to facilitate building more computationally efficient and robust ensemble SDMs, and it lends a practical tool to help understand the processes that contribute to prediction variability among SDMs. [ABSTRACT FROM AUTHOR]

The total arsenic concentration and the arsenic speciation in urine and feces samples of the two Giant Pandas living at Vienna zoo and of their feed, bamboo, were determined with ICPMS and HPLC-ICPMS. Urine was the main excretion route and accounted for around 90% of the ingested arsenic. The urinary arsenic concentrations were very high, namely up to 179 μg/L. Dimethylarsinic acid (DMA) was the dominating arsenic compound in the urine samples and ranged from 73 to 92% of the total arsenic, which is unusually high for a terrestrial mammal. The feces samples contained around 70% inorganic arsenic and 30% DMA. The arsenic concentrations in the bamboo samples were between 16 and 920 μg/kg dry mass. The main arsenic species in the bamboo extracts was inorganic arsenic. This indicates that the Giant Panda possesses a unique way of very efficiently methylating and excreting the provided inorganic arsenic. This could be essential for the survival of the animal in its natural habitat, because parts of this area are contaminated with arsenic. [ABSTRACT FROM AUTHOR]

As the rate-limiting enzyme of the mitochondrial respiratory chain, cytochrome c oxidase ( COX ) plays a crucial role in biological metabolism. “Living fossil” giant panda ( Ailuropoda melanoleuca ) is well-known for its special bamboo diet. In an effort to explore functional variation of COX1 in the energy metabolism behind giant panda's low-energy bamboo diet, we looked at genetic variation of COX1 gene in giant panda, and tested for its selection effect. In 1545 base pairs of the gene from 15 samples, 9 positions were variable and 1 mutation leaded to an amino acid sequence change. COX1 gene produces six haplotypes, nucleotide (pi), haplotype diversity (Hd). In addition, the average number of nucleotide differences (k) is 0.001629 ± 0.001036, 0.8083 ± 0.0694 and 2.517, respectively. Also, dN/dS ratio is significantly below 1. These results indicated that giant panda had a low population genetic diversity, and an obvious purifying selection of the COX1 gene which reduces synthesis of ATP determines giant panda's low-energy bamboo diet. Phylogenetic trees based on the COX1 gene were constructed to demonstrate that giant panda is the sister group of other Ursidae. [ABSTRACT FROM AUTHOR]

Enterocytozoon bieneusi is an emerging and opportunistic enteric pathogen triggering diarrhea and enteric disease in humans and animals. Despite extensive research on this pathogen, the prevalence and genotypes of E. bieneusi infection in precious wild animals of giant and red pandas have not been reported. In the present study, 82 faecal specimens were collected from 46 giant pandas ( Ailuropoda melanoleuca ) and 36 red pandas ( Ailurus fulgens ) in the northwest of China. By PCR and sequencing of the internal transcribed spacer (ITS) region of the ribosomal RNA (rRNA) gene of E. bieneusi , an overall infection rate of 10.98% (9/82) was observed in pandas, with 8.70% (4/46) for giant pandas, and 13.89% (5/36) for red pandas. Two ITS genotypes were identified: the novel genotype I-like ( n = 4) and genotype EbpC ( n = 5). Multilocus sequence typing (MLST) employing three microsatellites (MS1, MS3 and MS7) and one minisatellite (MS4) showed that nine, six, six and nine positive products were amplified and sequenced successfully at four respective loci. A phylogenetic analysis based on a neighbor-joining tree of the ITS gene sequences of E. bieneusi indicated that the genotype EbpC fell into 1d of group 1 of zoonotic potential, and the novel genotype I-like was clustered into group 2. The present study firstly indicated the presence of E. bieneusi in giant and red pandas, and these results suggested that integrated strategies should be implemented to effectively protect pandas and humans from infecting E. bieneusi in China. [ABSTRACT FROM AUTHOR]

Food resources are patchily distributed in the environment and carnivores and herbivores have adopted different foraging strategies to maximize feeding efficiency. One interesting strategy is that of the giant panda, a member of the Carnivora that has evolved into a bamboo specialist. Giant pandas forage discriminately, but it remains unknown how nutritional hierarchical levels and landscape configuration heterogeneity affect foraging patch selection. Here, we used global positioning system collars to track wild giant pandas at high resolution (<10 m) and sampled foraging patches for nutritional hierarchical level analysis. We predicted that giant pandas select foraging patches with microhabitat characteristics that decrease energy expenditure during foraging according to optimal search theory. We introduce the concept of nutrient load as the product of local patch nutrient concentration and predicted that relatively efficient nutrients in fluctuating nutritional environments may determine foraging patch selection in giant pandas. This is the first time that microhabitat characteristics, key nutrients and foraging behavior have been studied in combination in giant pandas. We used random forest (RF) and generalized linear mixed-effects models (GLMMs) to infer habitat and nutritional factors that may influence foraging patch selection and utilization. Our results reveal that giant pandas select foraging patches with a topography that likely decreases energy expenditure. Giant pandas also favor protein-rich foraging patches, probably because protein can be digested and assimilated faster than cellulose and this maximizes net energy gains. These data provide a new perspective on foraging patch selection strategies in heterogeneous habitats of diet-specialized species under constant nutritional challenge. Improved conservation planning can be undertaken according to our findings. [ABSTRACT FROM AUTHOR]

Abstract: The Wenchuan earthquake of May 2008 was a severe natural disaster that caused significant damage to the habitat of the endangered giant panda (Ailuropoda melanoleuca) inhabiting southwestern China. However, the effect of the earthquake on giant pandas is understudied. We took advantage of our long-term dataset on panda habitat use in the Minshan Mountains to investigate panda response to this disaster. We analyzed the habitat use patterns of giant pandas over the course of a 6-year period (5years pre-earthquake and 1year post-earthquake) along fixed-width line transects. We found that the habitat use patterns of giant pandas were stable before the earthquake and there was no obvious change after the earthquake (despite habitat loss that occurred). We argue that the Wenchuan earthquake does not appear to have been a significant threat for the giant panda. Our findings contribute to ongoing habitat restoration plans and long-term conservation of the giant panda. [Copyright &y& Elsevier]

Abstract: A new rare 20-membered macrocyclic lactam incorporating a diene conjugated olefin, designated sannastatin (1), together with the known structurally related vicenistatin (2), has been isolated from the cultures of Streptomyces sannanensis, a bacteria found in the feces of Ailuropoda melanoleuca. The structure of the new compound was established on the basis of extensive spectroscopic analyses including 1D- and 2D-NMR (1H–1H COSY, TOCSY, HSQC, HMBC, and NOESY) experiments. Compounds 1 and 2 displayed significant growth inhibitory activity against the brine shrimp (Artemia salina) larvae. [Copyright &y& Elsevier]

Abstract: Serum samples from 92 giant pandas in three captive facilities were tested for antibodies against five viruses of carnivores. Antibody titers against canine distemper virus (CDV) in two facilities in which giant pandas were vaccinated were variable. The canine adenovirus (CAV-1) and canine parvovirus (CPV) titers in vaccinated group were both positive, but titers were not high and varied among individual except one vaccinated panda had extremely high CAV-1 titer, indicating infection with the field virus following vaccination. Our results suggest that the vaccines used for these giant pandas do not elicit consistent antibody titers. Antibody titers against CDV, CPV and CAV-1 in unvaccinated giant pandas were highly variable, especially CPV titer. Almost half of sera were CPV antibody positive, and CPV titers were high enough to suggest infection with the virus. Canine coronavirus (CCV) and canine parainfluenza virus (CPIV) titers were not detected in all serum samples. The results of this study emphasize the need for research on infectious diseases of giant pandas and development of suitable vaccines for the species. [Copyright &y& Elsevier]

Three novel norsesquiterpenoids, (2 R ,4 S ,8a R)-8,8a,1,2,3,4-hexahydro-2-hydroxy-4,8a-dimethyl-2(2 H)-naphthalenone (1), (1 S ,3 S ,4 S ,4a S ,8a R)-4,8a-dimethyloctahydronaphthalene-1,3,4a(3 H)-triol(2), (4 S ,4a S ,8a S)-octahydro-4a-hydroxy-4, 8a-dimethyl-1(2 H)-naphthalenone (3), as well as six other known analogues (4 – 9), were isolated from the culture broth of Streptomyces sp. XM17, an actinobacterial strain inhabiting the fresh feces of the giant panda Ailuropoda melanoleuca. The chemical structures of 1 – 3 were elucidated comprehensively by NMR spectroscopic and MS analyses, furthermore, the stereochemical configurations were resolved by NOESY experiments, along with ECD spectral and single-crystal X-ray crystallographic analyses. These compounds were then tested for their antiviral activities using the "pretreatment of virus" approach, which showed that most of these compounds were potent in inhibiting the entry of influenza A virus, with IC 50 values ranging from 5 to 49 nM and selectivity indices all above 500. [Display omitted] • Three novel norsesquiterpenoids and six known analogues were isolated from the culture broth of Streptomyces sp. XM17. • These compounds were potent antivirals with IC 50 values ranging from 5 to 49 nM and selectivity indices all above 500. • These norsesquiterpenoids may interact with the hemagglutinin (HA) of influenza A virus, blocking the entry of viruses. [ABSTRACT FROM AUTHOR]

Abstract: Phenolic compounds were studied in the culms of five bamboo species collected in China: Yushania chungii, Fargesia robusta, Fargesia denudata, Fargesia rufa and Fargesia scabrida. All the species are eaten by giant panda (Ailuropoda melanoleuca). The culms contained phenolic acids and flavonoids in small concentrations, except for F. robusta, which did not contain flavonoids in detectable amounts. The species differed from each other in their phenolic composition. For example, F. rufa with the highest number of compounds clearly differed from other species. There were also differences among sampling sites, which reflect the differences among genotypes. Furthermore, there were clear ontogenetic differences in the culms: some compounds were present in mature culms but not in young (1–2 year old) culms, while the concentrations of other compounds decreased with increasing age. Over all, the composition and concentrations of soluble phenolic compounds in the bamboo culms were affected by species, age and site. [Copyright &y& Elsevier]

Abstract: The cDNA fragment of ribosomal protein L26 (RPL26) was cloned from Ailuropoda melanoleuca using RT-PCR method. The cDNA fragment is composed of 475bp, containing an open reading frame of 145 amino acids. Alignment analyses indicated that the nucleotide sequence and the deduced amino acid sequence showed high identity to other known RPL26 sequences from vertebrates and invertebrates. The cDNA sequence was used to construct phylogenetic trees with other known vertebrate and invertebrate RPL26 sequences, and the obtained trees demonstrated similar topology with the classical systematics, indicating the potential value of RPL26 gene in phylogenetic analysis. [Copyright &y& Elsevier]

Abstract: The complete mitochondrial genome sequence of the giant panda, Ailuropoda melanoleuca, was determined by the long and accurate polymerase chain reaction (LA-PCR) with conserved primers and primer walking sequence methods. The complete mitochondrial DNA is 16,805 nucleotides in length and contains two ribosomal RNA genes, 13 protein-coding genes, 22 transfer RNA genes and one control region. The total length of the 13 protein-coding genes is longer than the American black bear, brown bear and polar bear by 3 amino acids at the end of ND5 gene. The codon usage also followed the typical vertebrate pattern except for an unusual ATT start codon, which initiates the NADH dehydrogenase subunit 5 (ND5) gene. The molecular phylogenetic analysis was performed on the sequences of 12 concatenated heavy-strand encoded protein-coding genes, and suggested that the giant panda is most closely related to bears. [Copyright &y& Elsevier]

Summary: The morphological differences in the muscles of mastication between the giant panda (Ailuropoda melanoleuca) and the Asiatic black bear (Ursus thibetanus) were sought to confirm the adaptational strategy of these muscles in the giant panda. We measured some skull characteristics and weighed the muscles of mastication, and macroscopically observed the muscles of mastication in the two species. The noticeable differences between the two species are classified as follows: (1) The size ratio of the zygomatic width was much larger in the giant panda than in the Asiatic black bear. (2) The weight ratio of the two pterygoid muscles was also much larger in the giant panda than in the Asiatic black bear. (3) The lateral slips of the temporal muscles are thicker and stronger in the Asiatic black bear than in the giant panda. (4) The deep layer of the masseter muscle was rostrocaudally divided, and a complicated running of tendons is observed in the giant panda. (5) The two pterygoid muscles were much larger and well-developed in the giant panda than in the Asiatic black bear. The points (1) and (4) may be related to the generation of the force necessary to chew the bamboo in the giant panda. We thought that the large mass of the masseter and temporal muscles are needed in this species. In the points of (2) and (5), the two pterygoid muscles were obviously different in form and weight ratio between the two species. We suggest that the two pterygoid muscles may act as an additional force generator to dorsoventrally press and crush bamboo stems. [Copyright &y& Elsevier]

Mining activities provide the increasing basic human needs of materials, and the pressures of mining operations on biodiversity have been widely recognized. The spatial coincidence between mining surfaces and protected areas (or biodiversity hotspots) were identified by many studies at the global, national, and landscape scales, but few studies have focused on the spatial overlap between mining activities and the protected areas of giant panda (Ailuropoda melanoleuca), which is a world-renowned vulnerable flagship species, whose habitat has been decreased and fragmented since the last century. In this paper, using the official data of mining operation areas, we applied spatial analyses to detect the correlation among mining surfaces, panda populations (77.4% of all wild individuals), as well as their habitat (61.8% of the whole territory) and protected areas. We proposed a biodiversity factor index (BDF) to empirically test the potential influences of mining activities on wildlife habitat or protected areas. The results showed that: 1) from 2010 to 2019, a total of 197 mining concessions were detected in the habitat and protected areas of pandas, covering an area of 354.60 km2; 2) the most important types of protected areas for conservation (e.g. strict nature reserve and national park) suffered the most impacts caused by mining activities; 3) the panda populations preferred better habitat and avoided the mining sites, but mining operations introduced threats to the high suitability habitat most; 4) the high mining density areas were concentrated in seven zones. Finally, we discussed the reasons why mining operations were extendedly overlapped with the protected areas of panda habitat. Based on the spatial and temporal distribution of mining activities on panda habitat, some priority areas for habitat restorations were presented, which would attenuate the immediate conflict between stakeholders' interests and conservation at the beginning of restoration and increase the habitat quality in the long term. [ABSTRACT FROM AUTHOR]