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Terri L Roth - One of the best experts on this subject based on the ideXlab platform.
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investigation of factors potentially associated with serum ferritin concentrations in the black Rhinoceros diceros bicornis using a validated Rhinoceros specific assay
Journal of Zoo and Wildlife Medicine, 2018Co-Authors: Jessye Wojtusik, Terri L RothAbstract:Abstract: Iron overload disorder (IOD) can lead to organ dysfunction and may exacerbate other diseases in the critically endangered black Rhinoceros (Diceros bicornis). It is important to develop methods for monitoring the progression of iron storage (hemosiderosis), diagnosing the disease, and evaluating treatments in this species. Traditionally, an equine enzyme immunoassay (EIA) was used to measure Rhinoceros ferritin, a serum protein correlated to iron stores. The goal of this study was to validate a Rhinoceros-specific assay and investigate factors potentially associated with ferritin concentrations in black Rhinoceros. A ferritin EIA developed for Sumatran Rhinoceros was validated for black Rhinoceros via Western blot analysis of liver ferritin and confirmed parallelism of serum samples to the EIA standard curve and used to analyze serum samples (n = 943) collected from 36 black Rhinoceros (<1–33 yr) at 14 U.S. institutions. Mean (±SEM) serum ferritin concentration was 6,738 ± 518 ng/ml (range: 85–...
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genomic analysis of demographic history and ecological niche modeling in the endangered Sumatran Rhinoceros dicerorhinus sumatrensis
Current Biology, 2018Co-Authors: Terri L Roth, Herman L Mays, Chihming Hung, Pei Jen L Shaner, James Denvir, Megan Justice, Shang Fang Yang, David A Oehler, Jun FanAbstract:Summary The vertebrate extinction rate over the past century is approximately 22–100 times greater than background extinction rates [1], and large mammals are particularly at risk [2, 3]. Quaternary megafaunal extinctions have been attributed to climate change [4], overexploitation [5], or a combination of the two [6]. Rhinoceroses (Family: Rhinocerotidae) have a rich fossil history replete with iconic examples of climate-induced extinctions [7], but current pressures threaten to eliminate this group entirely. The Sumatran Rhinoceros ( Dicerorhinus sumatrensis ) is among the most imperiled mammals on earth. The 2011 population was estimated at ≤216 wild individuals [8], and currently the species is extirpated, or nearly so, throughout the majority of its former range [8–12]. Understanding demographic history is important in placing current population status into a broader ecological and evolutionary context. Analysis of the Sumatran Rhinoceros genome reveals extreme changes in effective population size throughout the Pleistocene. Population expansion during the early to middle Pleistocene was followed by decline. Ecological niche modeling indicated that changing climate most likely played a role in the decline of the Sumatran Rhinoceros, as less suitable habitat on an emergent Sundaland corridor isolated Sumatran Rhinoceros populations. By the end of the Pleistocene, the Sundaland corridor was submerged, and populations were fragmented and consequently reduced to low Holocene levels from which they would never recover. Past events denuded the Sumatran Rhinoceros of genetic diversity through population decline, fragmentation, or some combination of the two and most likely made the species even more susceptible to later exploitation and habitat loss. Video Abstract
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serum ferritin concentration is not a reliable biomarker of iron overload disorder progression or hemochromatosis in the Sumatran Rhinoceros dicerorhinus sumatrensis
Journal of Zoo and Wildlife Medicine, 2017Co-Authors: Terri L Roth, Paul R Reinhart, Jennifer L KrollAbstract:Abstract The aim of this study was to determine if ferritin is a reliable biomarker of iron overload disorder (IOD) progression and hemochromatosis in the Sumatran Rhinoceros (Dicerorhinus sumatrensis) by developing a species-specific ferritin assay and testing historically banked samples collected from rhinos that did and did not die of hemochromatosis. Ferritin extracted from Sumatran rhino liver tissue was used to generate antibodies for the Enzyme Immunoassay. Historically banked Sumatran rhino serum samples (n = 298) obtained from six rhinos in US zoos (n = 290); five rhinos at the Sumatran Rhino Conservation Centre in Sungai Dusun, Malaysia (n = 5); and two rhinos in Sabah, Malaysia (n = 3) were analyzed for ferritin concentrations. Across all US zoo samples, serum ferritin concentrations ranged from 348 to 7,071 ng/ml, with individual means ranging from 1,267 (n = 25) to 2,604 ng/ml (n = 36). The ferritin profiles were dynamic, and all rhinos exhibited spikes in ferritin above baseline during the s...
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Feasibility Study of NMR Based Serum Metabolomic Profiling to Animal Health Monitoring: A Case Study on Iron Storage Disease in Captive Sumatran Rhinoceros (Dicerorhinus sumatrensis)
2016Co-Authors: Miki Watanabe, Terri L Roth, Stuart J. Bauer, Adam Lane, Lindsey E. Romick-rosendaleAbstract:A variety of wildlife species maintained in captivity are susceptible to iron storage disease (ISD), or hemochromatosis, a disease resulting from the deposition of excess iron into insoluble iron clusters in soft tissue. Sumatran Rhinoceros (Dicerorhinus sumatrensis) is one of the Rhinoceros species that has evolutionarily adapted to a low-iron diet and is susceptible to iron overload. Hemosiderosis is reported at necropsy in many African black and Sumatran Rhinoceroses but only a small number of animals reportedly die from hemochromatosis. The underlying cause and reasons for differences in susceptibility to hemochromatosis within the taxon remains unclear. Although serum ferritin concentrations have been useful in monitoring the progression of ISD in many species, there is some question regarding their value in diagnosing hemochromatosis in the Sumatran rhino. To investigate the metabolic changes during the development of hemochromatosis and possibly increase our understanding of its progression and individual susceptibility differences, the serum metabolome from a Sumatran Rhinoceros was investigated by nuclear magnetic resonance (NMR)-based metabolomics. The study involved samples from female Rhinoceros at the Cincinnati Zoo (n = 3), including two animals that died from liver failure caused by ISD, and the Sungai Dusun Rhinoceros Conservation Centre in Peninsular Malaysia (n = 4). Principal component analysis was performed to visually and statistically compare the metabolic profiles of the healthy animals. The results indicated that significant differences were present between the animals at the zoo and the animals in the conservation center. A comparison of the 43 serum metabolomes of three zoo Rhinoceros showed two distinct groupings, healthy (n = 30) and unhealthy (n = 13). A total of eighteen altered metabolites were identified in healthy versus unhealthy samples. Results strongly suggest that NMR-based metabolomics is a valuable tool for animal health monitoring and may provide insight into the progression of this and other insidious diseases.
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sexual maturation in the Sumatran Rhinoceros dicerorhinus sumatrensis
Zoo Biology, 2013Co-Authors: Terri L Roth, Paul R Reinhart, John S Romo, Dedi Candra, Andriansyah Suhaery, Monica A StoopsAbstract:To help save the Sumatran rhino from extinction, the captive breeding program must capitalize on each rhino's reproductive lifespan. Doing so requires knowing when calves are sexually mature. The goal of this study was to monitor physiological changes associated with sexual maturation in two captive born calves (one male and one female) to determine the approximate age of maturity for both sexes of this species. Fecal testosterone metabolites were monitored in the male calf from 6 months to 7 years of age, and fecal pregnane metabolites were measured in the female calf from 6 months to 5.5 years of age. In addition, rectal ultrasonography was employed to monitor changes in ovarian activity from 2 to 5.5 years of age. The male calf's fecal testosterone concentrations reached levels comparable to those detected in samples from adult males when he was 6–6.5 years of age. The first pre-ovulatory sized follicle was observed on the ovaries of the female calf when she was 4.75 years old, but fecal pregnane metabolite concentrations only reached maximum mean concentrations and variability when she was 5–5.5 years of age. Results from this study indicate that male and female Sumatran rhino calves are sexually mature at 6–6.5 and 5–5.5 years of age, respectively. Zoo Biol. 32:549–555, 2013. © 2013 Wiley Periodicals Inc.
Zainal Zahari Zainuddin - One of the best experts on this subject based on the ideXlab platform.
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dentinogenic ghost cell tumor in a Sumatran Rhinoceros
Open Access Journal, 2021Co-Authors: Annas Salleh, Zainal Zahari Zainuddin, Reza Tarmizi, Chee K Yap, Chianren Jeng, Mohd ZamrisaadAbstract:An adult female Sumatran Rhinoceros was observed with a swelling in the left infraorbital region in March 2017. The swelling rapidly grew into a mass. A radiograph revealed a cystic radiolucent area in the left maxilla. In June 2017, the Rhinoceros was euthanized. At necropsy, the infraorbital mass measured 21 cm × 30 cm. Samples of the infraorbital mass, left parotid gland, and left masseter muscle were collected for histopathology (Hematoxylin & Eosin, Von Kossa, Masson's trichrome, cytokeratin AE1/AE3, EMA, p53, and S-100). Numerous neoplastic epithelial cells showing pleomorphism and infiltration were observed. Islands of dentinoid material containing ghost cells and keratin pearls were observed with the aid of the two special histochemistry stains. Mitotic figures were rarely observed. All the neoplastic odontogenic cells and keratin pearls showed an intense positive stain for cytokeratin AE1/AE3, while some keratin pearls showed mild positive stains for S-100. All samples were negative for p53 and S-100 immunodetection. The mass was diagnosed as a dentinogenic ghost cell tumor.
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two variants of uterine leiomyoma in malaysia s last Sumatran Rhinoceros dicerorhinus sumatrensis
Veterinary Quarterly, 2020Co-Authors: Annas Salleh, Zainal Zahari Zainuddin, K C Yap, Mohamed Reza Mohamed Tarmizi, Mohd ZamrisaadAbstract:Following its capture in March 2014, an adult female Sumatran Rhinoceros frequently showed profuse vaginal bleeding. An ultrasonography suggested the presence of multiple reproductive lesions, including two uterine masses which were suspected to be leiomyomas. Soon after, an open pyometra was confirmed. Later in November 2019, the patient died and necropsy confirmed the presence of two uterine masses; one was located at the cervico-uterine junction and another in the uterine body, with pyometra, and cystic endometrial hyerplasia. Based on histological, special stains, and immunohistochemical examination, it was shown that one of the masses was composed of large, ovoid and polyhedral neoplastic mesenchymal cells with eosinophilic cytoplasm and a few binucleated cells surrounded by collagen fibres. It was tested positive for SMA and vimentin, while negative for desmin, cytokeratin AE1/AE3, EMA, CD34, and S100. The other mass was composed of mesenchymal cells undergoing myxoid degeneration as evidenced by the presence of glycosaminoglycan-rich matrix. It was tested positive for SMA, vimentin, partially positive for desmin, and negative for the other markers. With the aid of human medical nomenclature, these masses were diagnosed as epithelioid leiomyoma and myxoid leiomyoma, respectively. This report provides a clinical presentation, and histologic descriptions of the two variants of leiomyomas that have not been reported in veterinary medicine.
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genetics and the last stand of the Sumatran Rhinoceros dicerorhinus sumatrensis
Oryx, 2013Co-Authors: Benoit Goossens, Zainal Zahari Zainuddin, Milena Salgadolynn, Jeffrine J Rovieryan, Abdul Hamid Ahmad, Junaidi Payne, Senthilvel K S S Nathan, Laurentius AmbuAbstract:The Sumatran Rhinoceros Dicerorhinus sumatrensis is on the brink of extinction. Although habitat loss and poaching were the reasons of the decline, today's reproductive isolation is the main threat to the survival of the species. Genetic studies have played an important role in identifying conservation priorities, including for Rhinoceroses. However, for a species such as the Sumatran Rhinoceros, where time is of the essence in preventing extinction, to what extent should genetic and geographical distances be taken into account in deciding the most urgently needed conservation interventions? We propose that the populations of Sumatra and Borneo be considered as a single management unit.
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blood meal analysis of tabanid fly after it biting the rare Sumatran Rhinoceros
Asian pacific Journal of Tropical Biomedicine, 2013Co-Authors: Zainal Zahari Zainuddin, Jeffrine J Rovieryan, Abdul Hamid Ahmad, Laurentius Ambu, Wahap Marni, Junaidi PayneAbstract:Objective To demonstrate a noninvasive large mammalian genetic sampling method using blood meal obtained from a tabanid fly.
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mitochondrial dna variability and conservation genetics of the Sumatran Rhinoceros
Conservation Biology, 1997Co-Authors: Juan Carlos Morales, Zainal Zahari Zainuddin, Patrick Andau, Jatna Supriatna, Don J MelnickAbstract:Among mammalian species cited as endangered by the World Conservation Union (IUCN), the United States Department of the Interior (USDI), and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), the Sumatran Rhinoceros ( Dicerorhinus sumatrensis ) is one of the most threatened. Surviving populations are dwindling rapidly due to heavy poaching and habitat conversion (Fig. 1). On Sumatra alone the Rhinoceros population has declined by more than half from 420–875 to 235–320 individuals over the past decade (Captive Breeding Specialist Group Species Survival Commission of the IUCN 1993). The number of Sumatran Rhinoceros surviving today is between 413 and 563, and captive breeding programs established to contribute to the survival of this species have been unsuccessful (Foose & van Strien 1995). Managed breeding sanctuaries in natural habitats are being proposed as an alternative to captive breeding and as a refuge for rescued animals (Foose & van Strien 1995). These units are intended to concentrate large numbers of animals in protected areas. However, given all the conservation efforts being carried out on behalf of the Sumatran Rhinoceros (Khan 1989; Captive Breeding Specialist Group 1994) and the recent discussions surrounding these efforts (Rabinowitz 1995 a , 1995 b ; Andau 1995; Hutchins 1995; Foose et al. 1995; Sumardja 1995), genetic information on this species is strikingly sparse. We know little about the extent of genetic variability in remnant populations or the extent of genetic divergence among them. The little we do know is based on the slowly evolving mtDNA ribosomal genes, and thus is not adequate for conservation management of conspecific populations (Amato 1994; Morales & Melnick 1994). The purpose of our study was to survey the pattern and extent of genetic heterogeneity among the remaining populations of Sumatran Rhinoceros by analyzing the rapidly evolving mitochondrial control region. Our results constitute the most extensive contribution so far to our understanding of the genetic structure of the Sumatran rhino. These data, together with additional data from nuclear genes, will provide a genetic foundation that combined with other non-genetic data will further enhance the prospects of recovery of this highly endangered mammal.
Jessica R Brandt - One of the best experts on this subject based on the ideXlab platform.
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characterization of 29 polymorphic microsatellite markers developed by genomic screening of Sumatran Rhinoceros dicerorhinus sumatrensis
BMC Research Notes, 2021Co-Authors: Oliver A. Ryder, Jessica R Brandt, Sinta H Saidah, Kai Zhao, Yasuko Ishida, Isabella Apriyana, Widodo Ramono, Herawati Sudoyo, Helena SuryadiAbstract:The Sumatran Rhinoceros is critically endangered, with fewer than 100 individuals surviving across its current range. Accurate census estimates of the remaining populations are essential for development and implementation of conservation plans. In order to enable molecular censusing, we here develop microsatellite markers with amplicon sizes of short length, appropriate for non-invasive fecal sampling. Due to limited sample quantity and potential lack of genome-wide diversity, Illumina sequence reads were generated from two Sumatran Rhinoceros samples. Genomic screening identified reads with short tandem repeats and loci that were polymorphic within the dataset. Twenty-nine novel polymorphic microsatellite markers were characterized (A = 2.4; HO = 0.30). These were sufficient to distinguish among individuals (PID < 0.0001), and to distinguish among siblings (PID(sib) < 0.0001). Among rhinos in Indonesia, almost all markers were established as polymorphic and effective for genotyping DNA from fecal samples. Notably, the markers amplified and displayed microsatellite polymorphisms using DNA extracted from 11 fecal samples collected non-invasively from wild Sumatran Rhinoceros. These microsatellite markers provide an important resource for a census and genetic studies of wild Sumatran rhinos.
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genetic structure and diversity among historic and modern populations of the Sumatran Rhinoceros dicerorhinus sumatrensis
Journal of Heredity, 2018Co-Authors: Oliver A. Ryder, Jessica R Brandt, Peter J Van Coeverden De Groot, Kelsey E Witt, Paige K Engelbrektsson, Kristofer M Helgen, Ripan S Malhi, Alfred L RocaAbstract:The Sumatran Rhinoceros (Dicerorhinus sumatrensis), once widespread across Southeast Asia, now consists of as few as 30 individuals within Sumatra and Borneo. To aid in conservation planning, we sequenced 218 bp of control region mitochondrial (mt) DNA, identifying 17 distinct mitochondrial haplotypes across modern (N = 13) and museum (N = 26) samples. Museum specimens from Laos and Myanmar had divergent mtDNA, consistent with the placement of western mainland rhinos into the distinct subspecies D. s. lasiotis (presumed extinct). Haplotypes from Bornean rhinos were highly diverse, but dissimilar from those of other regions, supporting the distinctiveness of the subspecies D. s. harrissoni. Rhinos from Sumatra and Peninsular Malaysia shared mtDNA haplotypes, consistent with their traditional placement into a single subspecies D. s sumatrensis. Modern samples of D. s. sumatrensis were genotyped at 18 microsatellite loci. Rhinos within Sumatra formed 2 sub-populations, likely separated by the Barisan Mountains, though with only modest genetic differentiation between them. There are so few remaining Sumatran Rhinoceros that separate management strategies for subspecies or subpopulations may not be viable, while each surviving rhino pedigree is likely to retain alleles found in no other individuals. Given the low population size and low reproductive potential of Sumatran rhinos, rapid genetic erosion is inevitable, though an under-appreciated concern is the potential for fixation of harmful genetic variants. Both concerns underscore 2 overriding priorities for the species: 1) translocation of wild rhinos to ex situ facilities, and 2) collection and storage of gametes and cell lines from every surviving captive and wild individual.
Junaidi Payne - One of the best experts on this subject based on the ideXlab platform.
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will current conservation responses save the critically endangered Sumatran Rhinoceros dicerorhinus sumatrensis
Oryx, 2016Co-Authors: Rasmus Gren Havmoller, Junaidi Payne, Widodo S Ramono, Susie Ellis, K Yoganand, Barney Long, Eric Dinerstein, Christy A Williams, Rudi H Putra, Jamal GawiAbstract:The Critically Endangered Sumatran Rhinoceros Dicerorhinus sumatrensis formerly ranged across South-east Asia. Hunting and habitat loss have made it one of the rarest large mammals and the species faces extinction despite decades of conservation efforts. The number of individuals remaining is unknown as a consequence of inadequate methods and lack of funds for the intensive field work required to estimate the population size of this rare and solitary species. However, all information indicates that numbers are low and declining. A few individuals persist in Borneo, and three tiny populations remain on the Indonesian island of Sumatra and show evidence of breeding. Rhino Protection Units are deployed at all known breeding sites but poaching and a presumed low breeding rate remain major threats. Protected areas have been created for the Rhinoceros and other in situ conservation efforts have increased but the species has continued to go locally extinct across its range. Conventional captive breeding has also proven difficult; from a total of 45 Sumatran Rhinoceros taken from the wild since 1984 there were no captive births until 2001. Since then only two pairs have been actively bred in captivity, resulting in four births, three by the same pair at the Cincinnati Zoo and one at the Sumatran Rhino Sanctuary in Sumatra, with the sex ratio skewed towards males. To avoid extinction it will be necessary to implement intensive management zones, manage the metapopulation as a single unit, and develop advanced reproductive techniques as a matter of urgency. Intensive census efforts are ongoing in Bukit Barisan Selatan but elsewhere similar efforts remain at the planning stage.
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will current conservation responses save the critically endangered Sumatran Rhinoceros dicerorhinus sumatrensis r asmus g ren h avmoller j unaidi p ayne w idodo r amono s usie e llis k y oganand b arney l ong e ric d inerstein a c hristy w illiams r
2015Co-Authors: Rasmus Gren, Junaidi Payne, Eric Dinerstein, Rudi H Putra, Borneo Rhino, A Christy, Gawi Leuser, Kumar Talukdar, Neil D BurgessAbstract:The Critically Endangered Sumatran Rhinoceros Dicerorhinus sumatrensis formerly ranged across South- east Asia. Hunting and habitat loss have made it one of the rarest large mammals and the species faces extinction despite decades of conservation efforts. The number of in- dividuals remaining is unknown as a consequence of inad- equate methods and lack of funds for the intensive field work required to estimate the population size of this rare and solitary species. However, all information indicates that numbers are low and declining. A few individuals per- sist in Borneo, and three tiny populations remain on the Indonesian island of Sumatra and show evidence of breed- ing. Rhino Protection Units are deployed at all known breeding sites but poaching and a presumed low breeding rate remain major threats. Protected areas have been created for the Rhinoceros and other in situ conservation efforts have increased but the species has continued to go locally extinct across its range. Conventional captive breeding has also proven difficult; from a total of Sumatran Rhinoceros taken from the wild since there were no captive births until . Since then only two pairs have been actively bred in captivity,resultingin four births, three bythe same pairat the Cincinnati Zoo and one at the Sumatran Rhino Sanctuary in Sumatra, with the sex ratio skewed towards males. To avoid extinction it will be necessary to implement intensive management zones, manage the metapopulation as a single unit, and develop advanced reproductive techni- ques as a matter of urgency. Intensive census efforts are on- going in Bukit Barisan Selatan but elsewhere similar efforts remain at the planning stage.
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genetics and the last stand of the Sumatran Rhinoceros dicerorhinus sumatrensis
Oryx, 2013Co-Authors: Benoit Goossens, Zainal Zahari Zainuddin, Milena Salgadolynn, Jeffrine J Rovieryan, Abdul Hamid Ahmad, Junaidi Payne, Senthilvel K S S Nathan, Laurentius AmbuAbstract:The Sumatran Rhinoceros Dicerorhinus sumatrensis is on the brink of extinction. Although habitat loss and poaching were the reasons of the decline, today's reproductive isolation is the main threat to the survival of the species. Genetic studies have played an important role in identifying conservation priorities, including for Rhinoceroses. However, for a species such as the Sumatran Rhinoceros, where time is of the essence in preventing extinction, to what extent should genetic and geographical distances be taken into account in deciding the most urgently needed conservation interventions? We propose that the populations of Sumatra and Borneo be considered as a single management unit.
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blood meal analysis of tabanid fly after it biting the rare Sumatran Rhinoceros
Asian pacific Journal of Tropical Biomedicine, 2013Co-Authors: Zainal Zahari Zainuddin, Jeffrine J Rovieryan, Abdul Hamid Ahmad, Laurentius Ambu, Wahap Marni, Junaidi PayneAbstract:Objective To demonstrate a noninvasive large mammalian genetic sampling method using blood meal obtained from a tabanid fly.
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debate forum preventing the extinction of the Sumatran Rhinoceros
2013Co-Authors: Abdul Hamid Ahmad, Junaidi Payne, Zainal Zaharu ZainuddinAbstract:Sumatran rhino (SR), Dicerorhinus sumatrensis, represents one the oldest surviving mammal genera. Due to its role in traditional Chinese medicines, the horn of SR has been sought for well over a millennium and for many years the price of SR horn by weight rivalled that of gold. Extensive hunting lead to a precipitous decline in distribution and numbers of SR, particularly during the first decades of the twentieth century (van Strien, 1975) and it seems little short of a miracle that the species is not already extinct. By the mid twentieth century, the species was depleted from its former range and in danger of extinction in Malaya and Borneo (Hubback, 1939; Metcalf, 1961; Medway, 1977; Rookmaaker, 1977), and elsewhere on mainland Asia (Harper, 1945). Flynn and Abdullah (1984) suggested 52-75 SR roamed Peninsular Malaysia in the early 1980s, including 20- 25 individuals in the Endau-Rompin area, while Davies and Payne (1982) estimated 15-30 SRs in Sabah. By 1981, the only clear evidence of periodic breeding in wild SR in Malaysia was in Endau-Rompin and the Tabin area of eastern Sabah. At that time, the species was disappearing rapidly from the 20 or more locations where it had been present just a few decades earlier (Payne, 1990). Zainal Zahari (1995) found evidence of only five SRs, all adults, in Endau-Rompin by 1995, showing that published estimates of SR numbers were notoriously unreliable, and that actual numbers had declined by half over the preceding decade. The 1995– 1998 Global Environment Facility-UNDP Sumatran Rhinoceros Conservation Strategy project saw SR numbers declining still further, but inflated numbers kept appearing in public domain, largely due to some proponents’ disbelief that two decades of effort had failed. Zainal Zahari et al. (2001) plotted the disastrous decline of large mammals in Peninsular Malaysia from 1975-99.
Muhammad Agil - One of the best experts on this subject based on the ideXlab platform.
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ramifications of reproductive diseases on the recovery of the Sumatran Rhinoceros dicerorhinus sumatrensis mammalia perissodactyla rhinocerotidae
Journal of Threatened Taxa, 2020Co-Authors: N E Schaffer, Muhammad Agil, Zainal Z ZainuddinAbstract:The Sumatran Rhinoceros Dicerorhinus sumatrensis is on the edge of extinction. The decline of this species was initially attributed to poaching and habitat loss, but evidence presented here indicates that reproductive failure has also been a significant cause of loss, and continues to affect wild populations. Indonesia’s remaining populations of Sumatran Rhino are small and scattered, with limited access to breeding opportunities with unrelated mates. This leaves them subject to inbreeding and isolation-induced infertility, linked to fertility problems analyzed here. Sumatran Rhino females in captivity showed high rates (>70%) of reproductive pathology and/or problems with conception, which has significantly hindered the breeding program. Technological advances enabling examination immediately after capture revealed similarly high rates and types of reproductive problems in individuals from wild populations. The last seven Sumatran Rhino females captured were from areas with small declining populations, and six had reproductive problems. Going forward, capturing similarly compromised animals will take up valuable space and resources needed for fertile animals. The high risk of infertility and difficulty of treating underlying conditions, coupled with the decreasing number of remaining animals, means that the success of efforts to build a viable captive population will depend upon utilizing fertile animals and applying assisted reproductive techniques. Decades of exhaustive in situ surveys have not provided information relevant to population management or to ascertaining the fertility status of individual animals. Thus the first priority should be the capture of individuals as new founders from areas with the highest likelihood of containing fertile rhinos, indicated by recent camera trap photos of mothers with offspring. In Sumatra these areas include Way Kambas and parts of the Leuser ecosystem.
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reproductive biology of the Sumatran Rhinoceros dicerorhinus sumatrensis fischer 1814
2007Co-Authors: Muhammad AgilAbstract:MUHAMMAD AGIL. Reproductive Biology of the Sumatran Rhinoceros (Dicerorhinus sumatrensis, FISCHER 1814). Under supervision of BAMBANG PURWANTARA as a chairman, HADI S ALIKODRA, J. KEITH HODGES and MOZES R. TOELIHERE as members of the Advisory Committee. The Sumatran Rhinoceros is the most critically endangered Rhinoceros species, with fewer than 300 animals left worldwide and an extremely high rate of decline (50% of wild population lost over the last decade). Very few Sumatran rhinos are to date kept in captivity only about 9 animals distributed worldwide. Moreover, although the species has been kept since the early 19 century, captive breeding program is not really successful because only three offspring have been born in captivity. The first offspring was born in 2001 in Cincinnati Zoo, USA. There are a number of reasons for this failure in captive breeding, such as a lack of understanding of the reproductive biology and there were no reliable methods for monitoring reproductive status in the Sumatran Rhinoceros. Therefore, the study was focused on the development of appropriate methods for monitoring reproductive status non-invasively and to study various reproductive aspects of the species. The female Sumatran Rhinoceros excreted oestrogen predominantly into urine (67.8%), whereas 14C-progesterone metabolites were almost exclusively (99.4%) eliminated via the faeces. Oestradiol-17β glucuronide is the only abundant oestrogen in urine, whereas oestrone is the major oestrogen in faeces, with oestradiol-17β being less abundant. Progesterone metabolites are more complex and resulted in the excretion of three major metabolites, two pregnanediols, one of which was 5βpregnane-3α, 20α-diol, and a 5-reduced 20-oxo pregnane, being identified as 5β-pregnane-3α-ol-20-one. E2 and progesterone metabolites were excreted into urine within the first 24 h (time lag). In contrast, progesterone metabolites were excreted into faeces occurred within 48 hours, while oestrogen metabolites were eliminated into faeces within 72 hours. Measurement of 5-P-3OH in faeces and E2 in urine can be used for monitoring oestrous cycles, determining oestrous cycle disorders and pregnancy in the Sumatran Rhinoceros. 5-P-3OH immunoreactive levels during the presumed luteal phase (17.3 + 6.4 μg/g dry faeces) were on average two to three fold higher compared to the presumed follicular phase (7.8 + 3.8 μg/g dry faeces). E2 immunoreactive concentration during follicular phase is higher 3-6 fold (28.2-335.8 ng/mg Cr, median value 96.7 ng/mg Cr) compared to E2 level during luteal phase (8.9-191.9 ng/mg Cr, median value 33.4 ng/mg Cr). Oestrous cycle length in the Sumatran Rhinoceros is about 23-24 days, with the length of follicular and luteal phase about 6 days and 17 days, respectively. Pregnancy length was recorded for 475 days, and early pregnancy could be detected after day-60 according to 5-P-3OH level using single faecal sample. 5-P-3OH arose significantly (46.3 μg/gr dry faeces) after day-60 above the highest 5-P-3OH values during luteal phase. Since then, 5-P-3OH level steady increased during pregnancy up to 10-20 fold (344.2-787.1 μg/gr dry faeces) higher than luteal level. Ultrasound examinations of ovaries and observation on changes in vulval appearance provide useful information on female reproductive status which can be used as a tool for monitoring the oestrous cycle when endocrine measurement is not possible. Monitoring daily changes in vulval appearance and occurrence of initial stages of sexual behaviour are useful to determine a proper timing for pairing since intensive vulval coloration and interest between the sexes usually occurs a few days prior to ovulation. Mating behaviour always occurred when follicle develop to reach dominant size (∅ 19-25 mm). 5-P-3OH levels were on average two fold lower during the period when sexual behaviour occurred compared to when it not occurred and the difference in levels was highly statistically significant. The study has provided the first data on the characterization of the fresh ejaculates obtained from artificial semen collection methods. A combination of AGM, PM and AV yielded a higher success rate in stimulating ejaculate compared to the other collection methods, however semen quality appeared to be better when PM and AV without AGM was applied. In comparison to other rhino species using the same semen collection methods, the volume of ejaculates and sperm concentration was very low. The results indicate that the male Torgamba presumably has a low fertilization capacity as a result of low sperm concentrations, so called oligozoospermia and low ejaculate volume, so called oligospermia. Non-invasive monitoring reproductive status can be used to evaluate reproduction in the Sumatran Rhinoceros e.g., characterization of oestrous cycle, early pregnancy detection, pregnancy monitoring, and to determine reproductive disorder. This study could contribute and support breeding success of the Sumatran Rhinoceros as part of the conservation program of the species through providing reliable information on proper time for pairing. The established method could facilitate and support field work on investigating fertility status of wild rhinos using single faecal sample to determine pregnancy in the rhino population through progestins analysis. GENERAL INTRODUCTION
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metabolism and excretion of oestradiol 17β and progesterone in the Sumatran Rhinoceros dicerorhinus sumatrensis
Animal Reproduction Science, 1998Co-Authors: Michael Heistermann, Muhammad Agil, A Buthe, J K HodgesAbstract:H-labelled oestradiol-17b and 14 C-progesterone were injected i.v. into an adult female . Sumatran Rhinoceros Dicerorhinus sumatrensis and all urine and faeces collected over 4 days. Of the injected steroid, 68% of 3 H-oestradiol and 89% of 14 C-progesterone were recovered. Peak excretion in urine occurred on day 1 for both steroids, and for faeces on day 2 for 14 C-pro- gesterone, and between days 2 and 3 for 3 H-oestradiol. Oestradiol metabolites were predominantly .nearly 70% excreted into the urine, while progesterone metabolites were almost exclusively . . ) 99% excreted into the faeces. The majority ) 70% of urinary excreted oestrogens consisted . of water-soluble i.e., conjugated forms, with ) 90% of these being glucuronides. In contrast, ) 75% of faecal oestrogen and progesterone metabolites were excreted as ether-soluble i.e., . unconjugated forms. HPLC co-chromatography of oestrogens in hydrolysed urine indicated only one peak of radioactivity, co-eluting with authentic oestradiol-17 b, whereas two peaks of radioactivity were found after HPLC of faecal oestrogens, the major one co-eluting with oestrone and the less prominent one with oestradiol-17b. Progesterone was excreted as numerous metabo- lites into the faeces. The three most abundant of these were identified using HPLC and gas . chromatography mass spectrometry GCMS as 5b-pregnane-3a ,20a-diol, 5b-pregnane-3a-ol-20- one, and a second pregnanediol, the exact structure of which could not be deduced. Measurement of urinary oestradiol-17b and faecal immunoreactive pregnanediol and 5a-pregnane-3a-ol-20-one
