Infantile hemangioma in a subadult Chinese pangolin: a case report.

BACKGROUND: Hemangiomas are a relatively common type of tumor in humans and animals. Various subtypes of hemangiomas have been described in the literature. The classification methods for hemangiomas differ between human and veterinary medicine, and the basis for tumor classification can be found in the literature. CASE PRESENTATION: This study describes a tumor in the subcutaneous tissue of the right dorsum of an artificially rescued juvenile Chinese pangolin. Computed tomography (CT) examination yielded the preliminary diagnosis of a vascular malformation, and surgery was performed to resect the tumor. Histopathological examination showed that the tumor mainly was consisted of adipose tissue, capillaries, and spindle cells in the fibrous stroma. Immunohistochemistry showed the positive expression of CD31, CD34, α-SMA, GLUT1 and WT-1 in the tumor tissue, and the tumor was eventually diagnosed as an infantile haemangioma. CONCLUSION: The final diagnosis of infantile hemangioma was depended on the histopathological immunohistochemical and CT examination of the neoplastic tissue. This is the first report of infantile hemangioma in a critically endangered species Chinese pangolin.

First case report of pustules associated with Escherichia fergusonii in the chinese pangolin (Manis pentadactyla aurita).

BACKGROUND: Escherichia fergusonii is a common conditionally pathogenic bacterium that infects humans and animals. E. fergusonii has been reported to cause diarrhea, respiratory disease, and septicemia, but it is rarely reported to cause skin infections in animals. E. fergusonii has been isolated from the skin and muscular tissue of Chinese pangolin (Manis pentadactyla aurita). To date, there have been no reports of Chinese pangolins with clinical signs of skin diseases. CASE PRESENTATION: This case report describes the clinical case of a subadult (bodyweight: 1.1 kg) female Chinese pangolin from wild rescue with pustules and subcutaneous suppurative infection due to E. fergusonii in the abdominal skin. Bacterial culture, Biochemical analysis, PCR and histopathology were utilized to identify the bacteria in the pustule puncture fluid and infected tissue. To the best of our knowledge, this is the first report of E. fergusonii-related pustules on a Chinese pangolin. CONCLUSION: This case report presents the first observed skin infection in a Chinese pangolin. E. fergusonii infection should be considered as a possible differential diagnosis of pustules and subcutaneous suppurative skin conditions in Chinese pangolins, and we also provide several recommendations for the diagnosis and treatment of this disease.

Sperm collection and characteristics analysis of the critically endangered Chinese pangolin (Manis pentadactyla).

The Chinese pangolin (Manis pentadactyla) is a critically endangered species. However, there is a paucity of research on the male reproductive gamete biology of this species. The present study was the first to systematically analyse the sperm characterization of the Chinese pangolin, including semen collection, sperm morphometry and ultrastructure. The semen of five male Chinese pangolins was successfully collected using the electroejaculation method. CASA (computer-assisted sperm analysis) was used to assess semen quality and take images for sperm morphometric analysis. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used for sperm ultrastructure observation. The results showed that the semen of the Chinese pangolin was yellow to pale yellow in colour, viscous, with a fishy odour, and a slightly alkaline pH of between 7.7 and 7.9. The head defects were the main sperm defects; there were 13 kinds of head defects counted in this study. The total sperm length, head length, head width and tail length were 67.62 ± 0.21 µm, 10.47 ± 0.06 µm, 1.33 ± 0.006 µm and 57.16 ± 0.20 µm, respectively. SEM observed that the spermatozoa had a rod-shaped head with a distinct apical ridge, which was different from most mammals and similar to that in avians and reptiles. Interestingly, TEM found that the acrosome membrane of the Chinese pangolin had a double membrane structure rather than a multiple bi-lamellar membrane structure as reported by the previous study. Collectively, this study contributes to the development of artificial breeding efforts and assisted reproductive techniques for the Chinese pangolin, as well as providing technical support for research on germplasm conservation of this species.

Automatic Identification of Pangolin Behavior Using Deep Learning Based on Temporal Relative Attention Mechanism.

With declining populations in the wild, captive rescue and breeding have become one of the most important ways to protect pangolins from extinction. At present, the success rate of artificial breeding is low, due to the insufficient understanding of the breeding behavior characteristics of pangolins. The automatic recognition method based on machine vision not only monitors for 24 h but also reduces the stress response of pangolins. This paper aimed to establish a temporal relation and attention mechanism network (Pangolin breeding attention and transfer network, PBATn) to monitor and recognize pangolin behaviors, including breeding and daily behavior. There were 11,476 videos including breeding behavior and daily behavior that were divided into training, validation, and test sets. For the training set and validation set, the PBATn network model had an accuracy of 98.95% and 96.11%, and a loss function value of 0.1531 and 0.1852. The model is suitable for a 2.40 m × 2.20 m (length × width) pangolin cage area, with a nest box measuring 40 cm × 30 cm × 30 cm (length × width × height) positioned either on the left or right side inside the cage. A spherical night-vision monitoring camera was installed on the cage wall at a height of 2.50 m above the ground. For the test set, the mean Average Precision (mAP), average accuracy, average recall, average specificity, and average F1 score were found to be higher than SlowFast, X3D, TANet, TSN, etc., with values of 97.50%, 99.17%, 97.55%, 99.53%, and 97.48%, respectively. The recognition accuracies of PBATn were 94.00% and 98.50% for the chasing and mounting breeding behaviors, respectively. The results showed that PBATn outperformed the baseline methods in all aspects. This study shows that the deep learning system can accurately observe pangolin breeding behavior and it will be useful for analyzing the behavior of these animals.

Comparison of Venous Blood Gas and Biochemical Parameters in Sunda Pangolin (Manis javanica) and Chinese Pangolin (Manis pentadactyla) before and after Isoflurane Anesthesia.

Venous blood gas analytes are commonly examined in animals, and the results may be important when evaluating the overall health status of an animal. Pangolins are critically endangered mammals, and there is limited information on their physiological reference values in the literature. The aim of this study was to analyze venous blood gas and biochemical parameters before and during isoflurane anesthesia in wild healthy Sunda and Chinese pangolins. The results obtained showed that the blood gas index trends of the two pangolin species before and after isoflurane anesthesia were the same. After anesthesia, the partial pressure of carbon dioxide (pCO2), partial pressure of oxygen (pO2), total carbon dioxide (CO2), mean blood bicarbonate (HCO3-), extracellular fluid compartment (BEecf) base excess and the mean blood glucose (Glu) levels of both pangolin species showed a significant increase compared to the pre-anesthesia period. In contrast, the mean blood potassium (K+), lactate (Lac) and mean blood pH levels were significantly lower. No significant differences in the mean blood sodium (Na+) or blood ionized calcium (iCa) levels were observed during anesthesia. This study is important for future comparisons and understanding the health status of this endangered species.

Energy budgets of captive Chinese pangolins (Manis pentadactyla).

The Chinese pangolin is an endangered species, and ex situ conservation and captive rescue are important conservation measures. This requires reliable information on nutritional energy requirements and expenditure characteristics. However, we lack sufficient knowledge of their energy physiology to determine their energy requirements for maintenance and growth. An open-flow respirometry system was used to measure the resting metabolic rate (RMR) and the daily energy expenditure (DEE) of Chinese pangolins (Manis pentadactyla), and the dietary digestive energy was measured. The average RMR in Chinese pangolins was 3.23 ml O2 kg-1 min-1 at an ambient temperature (Ta) of 24.5-30°C, which was only 73.0% of the expected value based on body mass (BM). The average DEE values were 744.9 kJ day-1 in animals with BM >3 kg and 597.3 kJ day-1 in those with BM <3 kg, which were only 52.4% and 60.6% of the predicted values, respectively. The RMR and DEE levels of the Chinese pangolin were lower than those of similar-sized eutherian mammals and close to those of anteaters. These characteristics suggest that the Chinese pangolin has a low demand for energy in its diet. Although metabolic level data alone cannot be used to calculate the energy requirements of each Chinese pangolin, we believe they can provide a tangible reference for the relocation of Chinese pangolins. These results provide a scientific basis for future research on the physiology and ecology of endangered wildlife such as the Chinese pangolin.

Influence of Pleistocene climate fluctuations on the demographic history and distribution of the critically endangered Chinese pangolin (Manis pentadactyla).

BACKGROUND: Pleistocene climate fluctuations have strongly modified species genetic diversity and distributions. The Chinese pangolin (Manis pentadactyla) has been recognized as a critically endangered animal due to heavy poaching and trafficking. However, the effect of Pleistocene climate fluctuations on the genetic diversity and spatial distribution of the Chinese pangolin remains largely unknown. Here, we combined whole genome sequencing data, analysis of complete mitochondrial genomes, and a large amount of occurrence data from field surveys to infer the ancestral demographic history and predict the past spatial dynamics of the Chinese pangolin in Guangdong Province, China. RESULTS: Our results indicated that there were two subpopulations, which showed similar trends of population size change in response to past climatic changes. We estimated a peak effective population size (Ne) during the last interglacial (LIG), followed by a marked decrease (~ 0.5 to fivefold change) until the last glacial maximum (LGM) and a rebound to a small peak population size during the Mid-Holocene (MH). The estimated time of the separation event between two subpopulations was approximately 3,000-2,500 years ago (ka). We estimated that the distribution of suitable areas shrank by 14.4% from the LIG to LGM, followed by an expansion of 31.4% from the LGM to MH and has been stable since then. In addition, we identified an elevational shift and suitable area decreased significantly during the LGM, but that the geographic extent of suitable areas in the western region increased from the LIG to present. The eastern region of Guangdong Province had the highest habitat suitability across all the climate scenarios. CONCLUSIONS: Our results suggested that Pleistocene climate fluctuations played an important role in shaping patterns of genetic diversity and spatial distribution, and that human stressors likely contributed to the recent divergence of two Chinese pangolin subpopulations sampled here. We argue that a key protected area should be established in the eastern region of Guangdong Province. As such, this study provides a more thorough understanding of the impacts of Pleistocene climate fluctuations impacts on a mammalian species in southern China and suggests more robust management and conservation plans for this Critically Endangered species of special interest.

Epidemiological Study of Betacoronaviruses in Captive Malayan Pangolins.

The coronavirus disease 2019 (COVID-19) outbreak has significantly affected international public health safety. It has been reported that the pathogen severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes COVID-19, could originate from bats and utilize the Malayan pangolin (Manis javanica) as an intermediate host. To gain further insights into the coronaviruses carried by pangolins, we investigated the occurrence of Betacoronavirus (ß-CoV) infections in captive Malayan pangolins in the Guangdong province of China. We detected three ß-CoV-positive M. javanica individuals with a positive rate of 6.98% and also detected ß-CoV in two dead pangolins sampled in August 2019. The CoV carried by pangolins is a new ß-CoV, which is genetically related to SARS-CoV-2. Furthermore, the expression of angiotensin-converting enzyme 2 (ACE2) was detected in eight organs of pangolins, with the highest ACE2 mRNA levels in the kidney, suggesting that these organs could be at a risk of ß-CoV infection. These results enable us to better understand the status of ß-CoV carried by Malayan pangolins, while providing a theoretical basis for better pangolin protection and viral control.

Single cell atlas for 11 non-model mammals, reptiles and birds.

The availability of viral entry factors is a prerequisite for the cross-species transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Large-scale single-cell screening of animal cells could reveal the expression patterns of viral entry genes in different hosts. However, such exploration for SARS-CoV-2 remains limited. Here, we perform single-nucleus RNA sequencing for 11 non-model species, including pets (cat, dog, hamster, and lizard), livestock (goat and rabbit), poultry (duck and pigeon), and wildlife (pangolin, tiger, and deer), and investigated the co-expression of ACE2 and TMPRSS2. Furthermore, cross-species analysis of the lung cell atlas of the studied mammals, reptiles, and birds reveals core developmental programs, critical connectomes, and conserved regulatory circuits among these evolutionarily distant species. Overall, our work provides a compendium of gene expression profiles for non-model animals, which could be employed to identify potential SARS-CoV-2 target cells and putative zoonotic reservoirs.

Phylogenetic relationship of Chinese pangolin (Manis pentadactyla aurita) revealed by complete mitochondrial genome.

The Chinese pangolin (Manis pentadactyla) is an extremely endangered species, it has been banned from international trade due to a sharp decline of the population number in China. It is difficult to distinguish among subspecies, thus making it entangled in law enforement. In order to clarify this chaos, we determined and annotated the whole mtDNA genome of the Chinese pangolin. The complete mitogenome is 16 573 bp in length, includeing 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and one control region. We built the phylogenetic tree of Chinese pangolinand other 7 most related Manis species.