Yirui Heng

Dr. Yirui Heng

orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 August 2021 in Parasitology Research
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Journal Article
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YHYirui Heng
Yirui Heng
SCShin Min Chong
Shin Min Chong
CHChia-Da Hsu
Chia-Da Hsu
AAAli Anwar Ahmad
Ali Anwar Ahmad

1 September 2023 in Journal of Zoo and Wildlife Medicine
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Journal Article
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YHYirui Heng
Yirui Heng
CYCharlene Yeong
Charlene Yeong
WYWenjiin Clara Yeo
Wenjiin Clara Yeo
AMAbraham Mathew
Abraham Mathew
Pangolins are amongst the most overexploited species in the world and all eight species of pangolins are threatened with extinction. These animals are rare in zoological collections and often suffer high mortality rates in captivity. Maintaining healthy populations in captivity has become more important with the declining populations in the wild, but knowledge of veterinary care of these animals is limited. Interpreting radiography and ultrasonography images in a patient can be challenging without knowledge of normal findings. The Wildlife Healthcare and Research Center (WHRC) at Mandai Wildlife Reserve (MWR) admits an average of 25 Sunda pangolins (Manis javanica) annually, which is a Critically Endangered species native to Singapore. All the pangolins are triaged on admission and anesthetized for a health assessment before release into the wild. Endotracheal intubation using an otoscope and stylet is a novel technique in the species that has been developed and is commonly performed with these pangolins. A retrospective study was done on 20 clinically healthy wild pangolins to determine normal ultrasonography and radiography findings in the species. Notable findings include the presence of radio-opaque particles in the stomachs of all pangolins, the presence of free fluid cranial to the left kidney (13/20), a spleen with multifocal hypoechoic regions (6/20), and open epiphyseal plates of long bones even in large individuals weighing as heavy as 6.8 kg. Ultrasonographic images and measurements of kidney, spleen, and adrenal gland sizes as well as intestinal, gallbladder, and urinary bladder wall thickness were also described. These diagnostic imaging findings can advance the veterinary care of captive and wild pangolins.

18 October 2022 in Journal of Comparative Pathology
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Journal Article
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SCShin M. Chong
Shin M. Chong
YHYirui Heng
Yirui Heng
AAAli A. Ahmad
Ali A. Ahmad
CHChia-Da Hsu
Chia-Da Hsu

22 March 2022 in Journal of Medical Primatology
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Journal Article
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SCShin Min Chong
Shin Min Chong
Guillaume DouayGuillaume Douay
Guillaume Douay
YHYirui Heng
Yirui Heng
YCYou Rong Chng
You Rong Chng
YTYih Hong Tay
Yih Hong Tay
WWWai Kwan Wong
Wai Kwan Wong

1 June 2023 in Journal of Zoo and Wildlife Medicine
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Journal Article
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YHYirui Heng
Yirui Heng
SSShangari D/O Sekar
Shangari D/O Sekar
RPRossella Panarese
Rossella Panarese
CHChia-Da Hsu
Chia-Da Hsu
SXShangzhe Xie
Shangzhe Xie
An outbreak of the nematode Strongyloides sp. occurred in a population of 18 male and 29 female panther chameleons (Furcifer pardalis) at the Singapore Zoo. The parasite was first detected in one individual during routine microscopic examination of feces using the direct examination and magnesium sulfate flotation methods. The parasite was later found to have a closest match (98.96%) with Strongyloides sp. Okayama by DNA sequencing. Over a period of 6 mon, 97.9% (46/47) of the panther chameleons tested positive for the parasite, and 25.5% (12/47) of the animals died due to the disease. All the animals that died were female. Of the positive tests, magnesium sulfate flotation identified the parasite 98.1% (105/107) of the time, compared to direct fecal microscopy, which identified the parasite only 43.9% (47/107) of the time. Parasite eggs were detected in 100% (105/105) of the positive magnesium sulfate flotation tests but only 66.0% (31/47) of the positive direct fecal microscopy tests. Parasite larvae were detected in 61.7% (29/47) of the positive direct fecal microscopy tests but only 9.5% (10/105) of the magnesium sulfate flotation tests. Treatments with fenbendazole and pyrantel pamoate at published doses were ineffective at eliminating the parasite. Ivermectin (0.2 mg/kg PO q2wk for two doses) was successful at treating the parasite, with all animals testing negative for the parasite at the end of the treatment course without any observed adverse reactions. However, complete eradication of the parasite could not be achieved, as Strongyloides sp. could still be detected in the population on routine coproscopy intermittently over 3 yr. There were no further mortalities due to the disease with prompt treatment with ivermectin. Strongyloidiasis may cause high morbidity in panther chameleons, but severe disease leading to mortality can be prevented with the use of ivermectin.

1 June 2023 in Journal of Zoo and Wildlife Medicine
Verified
Journal Article
Closed access
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YHYirui Heng
Yirui Heng
CHChia-Da Hsu
Chia-Da Hsu
AMAbraham Mathew
Abraham Mathew
POPei Yee Oh
Pei Yee Oh
WLWen-Ta Li
Wen-Ta Li
SXShangzhe Xie
Shangzhe Xie
Amebiasis caused by Entamoeba invadens is an important disease in reptile collections, causing severe morbidity and mortality. Surveillance of the parasite at the Singapore Zoo was carried out over a 4-yr period by PCR testing on reptiles that presented with lethargy and enteritis for disease investigation. Asymptomatic reptiles sharing the same enclosures as positive individuals were also tested as part of outbreak investigation. Animals in the collection that tested positive for the parasite were treated with metronidazole at various doses, with the addition of paromomycin for two cases, until a negative PCR test result was obtained at the end of the treatment course. A total of 97 samples from 49 individuals across 19 species of reptiles were obtained, of which 24 samples (24.7%) from 19 animals were positive for E. invadens. Of these positive samples, 11 samples were for disease investigation, eight samples for outbreak surveillance, and five samples for treatment monitoring. Treatment was initiated for 10 animals, four of which were showing clinical signs of disease. The parasite was cleared in nine of these 10 animals (90%), with eight animals receiving metronidazole as a sole therapeutic agent. A total of nine animals died of the disease, four of which (44.4%) presented dead or died within 24 h of presentation. Necrotizing enteritis was a consistent postmortem finding resulting in gastrointestinal perforation in two cases, and coelomic adhesions and hepatic trophozoites were each seen in five animals. The results suggest that the management of Entamoeba epizootics in the collection requires prompt outbreak investigation. Diagnosis of the disease with advanced diagnostic tools like PCR, endoscopy, and ultrasonography and treatment with metronidazole in both symptomatic and asymptomatic animals may reduce mortalities during an outbreak.