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Boonprasert K, Srivorakul S, Monchaivanakit N, Langkaphin W, Sripiboon S, Janyamethakul T, Srisa-ad C, Guntawang T, Brown JL, Thitaram C, Pringproa K. Characterizations of Elephant Endotheliotropic Herpesvirus Type 1A and 4 Co-Infections in Asian Elephant ( Elephas maximus) Calves. Vet Sci 2024; 11:147. [PMID: 38668415 PMCID: PMC11055005 DOI: 10.3390/vetsci11040147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 03/16/2024] [Accepted: 03/18/2024] [Indexed: 04/29/2024] Open
Abstract
Three cases of double infection with elephant endotheliotropic herpesvirus (EEHV) types 1A and 4 in captive Asian elephants are presented. The first calf was a 4-year-old female that showed initial signs of lethargy and depression. The second calf was a 6-year-old female that displayed signs of depression and diarrhea and died within 48 h of the start of supportive treatment. The third was a 2-year-old male that died suddenly while living with the herd. Necropsies were performed in the first and second elephants, while only a tongue sample was collected from the third calf. EEHV infection was confirmed via quantitative PCR (qPCR) and gene sequencing, revealing double subtypes of EEHV1A and -4 infections. This study describes the hematological and pathological characteristics within the host following double EEHV infection.
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Affiliation(s)
- Khajohnpat Boonprasert
- Elephant Hospital, National Elephant Institute, Forest Industry Organization, Lampang 52190, Thailand
- Center of Elephant and Wildlife Health, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Saralee Srivorakul
- Center of Veterinary Diagnostic and Technology Transfer, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Natcha Monchaivanakit
- Elephant Hospital, National Elephant Institute, Forest Industry Organization, Lampang 52190, Thailand
| | - Warangkhana Langkaphin
- Elephant Hospital, National Elephant Institute, Forest Industry Organization, Lampang 52190, Thailand
| | - Supaphen Sripiboon
- Department of Large Animal and Wildlife Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen Campus, Nakornpathom 73140, Thailand
| | | | | | - Thunyamas Guntawang
- Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Janine L. Brown
- Center for Species Survival, Smithsonian National Zoo and Conservation Biology Institute, 1500 Remount Rd., Front Royal, VA 22630, USA
| | - Chatchote Thitaram
- Center of Elephant and Wildlife Health, Chiang Mai University, Chiang Mai 50100, Thailand
- Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
- Elephant, Wildlife and Companion Animal Research Group, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Kidsadagon Pringproa
- Center of Elephant and Wildlife Health, Chiang Mai University, Chiang Mai 50100, Thailand
- Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
- Elephant, Wildlife and Companion Animal Research Group, Chiang Mai University, Chiang Mai 50100, Thailand
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Kosaruk W, Brown JL, Towiboon P, Pringproa K, Punyapornwithaya V, Tankaew P, Kittisirikul N, Toonrongchang W, Janyamathakul T, Muanghong P, Thitaram C. Seasonal patterns of oxidative stress markers in captive Asian elephants in Thailand and relationships to elephant endotheliotropic herpesvirus shedding. Front Vet Sci 2023; 10:1263775. [PMID: 37795017 PMCID: PMC10546319 DOI: 10.3389/fvets.2023.1263775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 09/06/2023] [Indexed: 10/06/2023] Open
Abstract
Introduction Oxidative stress refers to an imbalance between oxidant and antioxidant activity and accumulation of reactive oxygen species, which can have detrimental effects on animal health. Annual fluctuations in oxidative stress status can occur, increasing disease susceptibility during certain time periods. However, a full understanding of factors related to oxidative stress in Asian elephants and how to mitigate the negative consequences is lacking. Methods This study measured six serum oxidative stress markers [reactive oxygen species (ROS), malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), albumin, glutathione peroxidase (GPx), and catalase] and two stress markers [serum cortisol and fecal glucocorticoid metabolites (fGCM)] in 23 captive Asian elephants in Thailand over a 12 months period to examine relationships with age and season. Results Seasonal variations were observed, with several markers exhibiting significantly higher concentrations in the summer (ROS, MDA, 8-OHdG, albumin) and lower values during the rainy/winter seasons (MDA, 8-OHdG, albumin, catalase). By contrast, GPx was the only marker to be highest during the rainy season. For the stress markers, higher fGCM concentrations were noted during the rainy season, which contrasts with earlier studies showing more activity in the winter (tourist season). Positive correlations were found between the temperature-humidity index and ROS, GPx, and fGCM, while a negative correlation was observed with serum albumin. Elephant endotheliotropic herpesvirus (EEHV) shedding events were associated with higher concentrations of ROS and MDA. A moderate negative correlation was observed between 8-OHdG and the PCR threshold cycle of EEHV shedding (Ct), indicating DNA damage may be involved in EEHV shedding in elephants. Discussion Results revealed significant age and seasonal effects on several oxidative stress markers, indicating those factors should be considered in study design and data interpretation. There also may be physiological adaptations in oxidative stress conditions in relation to environmental changes that could impact health outcomes.
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Affiliation(s)
- Worapong Kosaruk
- Doctoral Degree Program in Veterinary Science, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
- Center of Elephant and Wildlife Health, Chiang Mai University Animal Hospital, Chiang Mai, Thailand
- Elephant, Wildlife, and Companion Animals Research Group, Chiang Mai University, Chiang Mai, Thailand
| | - Janine L. Brown
- Center of Elephant and Wildlife Health, Chiang Mai University Animal Hospital, Chiang Mai, Thailand
- Elephant, Wildlife, and Companion Animals Research Group, Chiang Mai University, Chiang Mai, Thailand
- Center for Species Survival, Smithsonian Conservation Biology Institute, Front Royal, VA, United States
| | - Patcharapa Towiboon
- Center of Elephant and Wildlife Health, Chiang Mai University Animal Hospital, Chiang Mai, Thailand
| | - Kidsadagon Pringproa
- Center of Elephant and Wildlife Health, Chiang Mai University Animal Hospital, Chiang Mai, Thailand
- Elephant, Wildlife, and Companion Animals Research Group, Chiang Mai University, Chiang Mai, Thailand
- Department of Veterinary Bioscience and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Veerasak Punyapornwithaya
- Department of Veterinary Bioscience and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Pallop Tankaew
- Central Laboratory, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Narueporn Kittisirikul
- Elephant Hospital, National Elephant Institute, Forest Industry Organization, Lampang, Thailand
| | | | | | | | - Chatchote Thitaram
- Center of Elephant and Wildlife Health, Chiang Mai University Animal Hospital, Chiang Mai, Thailand
- Elephant, Wildlife, and Companion Animals Research Group, Chiang Mai University, Chiang Mai, Thailand
- Department of Companion Animal and Wildlife Clinic, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
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Sittisak T, Guntawang T, Srivorakul S, Photichai K, Boonprasert K, Khammesri S, Chuammitri P, Thitaram C, Hsu WL, Thanawongnuwech R, Pringproa K. Response of elephant peripheral blood mononuclear cells when stimulated with elephant endotheliotropic herpesvirus glycoprotein B (EEHV-gB). Vet Immunol Immunopathol 2023; 258:110577. [PMID: 36867998 DOI: 10.1016/j.vetimm.2023.110577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 02/10/2023] [Accepted: 02/26/2023] [Indexed: 03/05/2023]
Abstract
Elephant endotheliotropic herpesvirus-hemorrhagic disease (EEHV-HD) is the most highly fatal infectious disease among young Asian elephants. Despite the fact that antiviral therapy has been widely used, its therapeutic outcomes remain uncertain. Additionally, the virus has yet to be successfully cultivated in vitro in the process of develop viral envelope glycoproteins for vaccine design. The present study aims to investigate and evaluate EEHV1A glycoprotein B (gB) antigenic epitopes as potential candidates for further vaccine development. Epitopes of EEHV1A-gB were employed in in silico predictions and designed by using online antigenic predicting tools. Candidate genes were then constructed, transformed and expressed in the E. coli vectors prior to examine their potential for acceleration elephant immune responses in vitro. Elephant peripheral blood mononuclear cells (PBMCs) isolated from 16 healthy juvenile Asian elephants were investigated for their proliferative capability and cytokine responses after being stimulated with EEHV1A-gB epitopes. Exposure of elephant PBMCs to 20 µg/mL of gB for 72 h resulted in a significant proliferation of CD3 + cells when compared with the control group. Furthermore, proliferation of CD3 + cells was associated with a marked up-regulation of cytokine mRNA expression, involving IL-1β, IL-8, IL-12 and IFN-γ. It remains to be determined whether these candidate EEHV1A-gB epitopes could activate immune responses in animal models or elephants in vivo. Our potentially promising results demonstrate a degree of feasibility for the use of these gB epitopes in expanding EEHV vaccine development.
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Affiliation(s)
- Tidaratt Sittisak
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Thunyamas Guntawang
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Saralee Srivorakul
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Kornravee Photichai
- Veterinary Diagnostic Center, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Khajohnpat Boonprasert
- Center of Excellence in Elephant and Wildlife Research, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Siripat Khammesri
- Center of Excellence in Elephant and Wildlife Research, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Phongsakorn Chuammitri
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Chatchote Thitaram
- Center of Excellence in Elephant and Wildlife Research, Chiang Mai University, Chiang Mai 50100, Thailand; Department of Companion Animals and Wildlife Clinics, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Wei-Li Hsu
- Graduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung Hsing University, Taichung 402, Taiwan
| | - Roongroje Thanawongnuwech
- Department of Pathology, Faculty of Veterinary Sciences, Chulalongkorn University, Bangkok 10330, Thailand
| | - Kidsadagon Pringproa
- Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; Center of Excellence in Elephant and Wildlife Research, Chiang Mai University, Chiang Mai 50100, Thailand.
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Sree Lakshmi P, Karikalan M, Sharma GK, Sharma K, Chandra Mohan S, Rajesh Kumar K, Miachieo K, Kumar A, Gupta MK, Verma RK, Sahoo N, Saikumar G, Pawde AM. Pathological and molecular studies on elephant endotheliotropic herpesvirus haemorrhagic disease among captive and free-range Asian elephants in India. Microb Pathog 2023; 175:105972. [PMID: 36621697 DOI: 10.1016/j.micpath.2023.105972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/19/2022] [Accepted: 01/03/2023] [Indexed: 01/07/2023]
Abstract
In the present research pathology and molecular diagnosis of elephant endotheliotropic herpes virus-haemorrhagic disease (EEHV-HD) among Asian elephants was studied. Out of 76 cases, 20 were positive for EEHV infection in PANPOL and POL1 based semi-nested PCR. Out of 20 samples, 10 samples were fatal cases of EEHV-HD while 10 were of either subclinical or latent infection. Acute onset haemorrhagic disease with EEHV-HD had anorexia, facial and neck swelling, cyanotic buccal mucosa and tongue, nasal and ocular discharge, and colic. The hallmark of gross finding in all cases were severe haemorrhagic lesions in the internal organs viz. cyanosis of tongue with multifocal petechial haemorrhages, diffuse epicardial and endocardial haemorrhages, swollen liver (rounded edges) with parenchymal haemorrhages, serosal and mucosal haemorrhages in gastrointestinal tract, congested kidneys with corticomedullary haemorrhages, highly congested meninges, and brain capillaries with haemorrhages. Microscopic findings in all the cases had severe vascular changes in the visceral organs. Microthrombi was present in the vasculature of tongue, heart, lung, liver, kidney, and brain. The endothelial lining of most of the blood vessels were swollen with apoptotic changes. Amphophilic to basophilic intranuclear inclusion bodies were observed in the endothelial cells. Immunostaining using anti-EEHV DNAPOL hyperimmune sera revealed intense positive signals in the endothelium of blood vessels and their walls. Quantification of viral load in necropsy tissue samples revealed highest in the heart (7.4 × 106/μg of sample) and least in the brain (9 × 103/μg of sample). The PCR amplicons from EEHV1 specific genes (POL1(U38) and TER were subjected to partial genome sequencing which had 99.9% similarity with the EEHV1A subtype. It was concluded that Asian elephants in India are latently infected for EEHV1 and in all the fatal EEHV-HD cases, EEHV1A subtype was the causative agent with characteristic pathomorphological changes in visceral organs.
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Affiliation(s)
- P Sree Lakshmi
- ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, 243122, Uttar Pradesh, India
| | - M Karikalan
- ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, 243122, Uttar Pradesh, India.
| | - Gaurav K Sharma
- ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, 243122, Uttar Pradesh, India
| | - Kirtika Sharma
- ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, 243122, Uttar Pradesh, India
| | - S Chandra Mohan
- ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, 243122, Uttar Pradesh, India
| | - K Rajesh Kumar
- Veterinary Officer, Mudumalai Tiger Reserve, The Nigiris, Tamil Nadu, India
| | - Kenei Miachieo
- Sarguja Elephant Reserve, Ambikapur, Chhattisgarh, India
| | - Ajay Kumar
- Bhagwan Birsa Biological Park, Ranchi, Jharkhand, India
| | - M K Gupta
- Faculty of Veterinary Science & Animal Husbandry, Ranchi, Jharkhand, India
| | - Rakesh K Verma
- Sarguja Elephant Reserve, Ambikapur, Chhattisgarh, India
| | - Niranjana Sahoo
- Faculty of Veterinary Science & Animal Husbandry, OUAT, Odisha, India
| | - G Saikumar
- ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, 243122, Uttar Pradesh, India
| | - A M Pawde
- ICAR- Indian Veterinary Research Institute, Izatnagar, Bareilly, 243122, Uttar Pradesh, India
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Hoornweg TE, Perera VP, Karunarathne RN, Schaftenaar W, Mahakapuge TA, Kalupahana AW, Rutten VP, de Haan CA. Young elephants in a large herd maintain high levels of elephant endotheliotropic herpesvirus-specific antibodies and do not succumb to fatal haemorrhagic disease. Transbound Emerg Dis 2022; 69:e3379-e3385. [PMID: 35757981 PMCID: PMC9796006 DOI: 10.1111/tbed.14644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 06/23/2022] [Accepted: 06/24/2022] [Indexed: 12/30/2022]
Abstract
Elephant endotheliotropic herpesviruses (EEHVs) have co-existed with elephants for millions of years, yet may cause fatal haemorrhagic disease (EEHV-HD), typically in elephants between 1 and 10 years of age. EEHV is omnipresent in (sub)adult elephants, and young elephants with low EEHV-specific antibody levels are at risk for EEHV-HD, suggesting that fatal disease may occur due to an insufficiently controlled primary infection. To further address this hypothesis, sera of three large elephant cohorts were subjected to a multiple EEHV species ELISA: (I) 96 Asian elephants between 0 and 57 years, including 13 EEHV-HD fatalities, from European zoo herds typically sized five to six elephants, (II) a herd of 64 orphaned elephants aged 0-15 years at the Elephant Transit Home in Sri Lanka and (III) 31 elephants aged 8-63 years, part of a large herd of 93 elephants at Pinnawala Elephant Orphanage, Sri Lanka. All Sri Lankan elephants showed high EEHV-specific antibody levels regardless of their age. While antibody levels of most European zoo elephants were comparable to those of Sri Lankan elephants, the average antibody level of the European juveniles (1-5 years of age) was significantly lower than those of age-matched Sri Lankan individuals. Moreover, the European juveniles showed a gradual decrease between 1 and 4 years of age, to be attributed to waning maternal antibodies. Maintenance of high levels of antibodies in spite of waning maternal antibodies in young Sri Lankan elephants is likely due to the larger herd size that increases the likelihood of contact with EEHV-shedding elephants. Together with the observation that low levels of EEHV-specific antibodies correlate with increased numbers of EEHV-HD fatalities, these results suggest that infection in presence of high maternal antibody levels may protect calves from developing EEHV-HD, while at the same time activating an immune response protective in future encounters with this virus.
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Affiliation(s)
- Tabitha E. Hoornweg
- Section of VirologyDivision Infectious Diseases and ImmunologyFaculty of Veterinary MedicineDepartment of Biomolecular Health SciencesUtrecht UniversityUtrechtThe Netherlands,Section of ImmunologyDivision Infectious Diseases and ImmunologyFaculty of Veterinary MedicineDepartment of Biomolecular Health SciencesUtrecht UniversityUtrechtThe Netherlands
| | - Vijitha P. Perera
- Department of Wildlife Conservation, Elephant Transit HomeUdawalaweSri Lanka
| | | | - Willem Schaftenaar
- Veterinary Advisor EAZA Elephant TAGRotterdam ZooRotterdamThe Netherlands
| | - Thilini A.N. Mahakapuge
- Faculty of Veterinary Medicine and Animal ScienceDepartment of Veterinary PathobiologyUniversity of PeradeniyaPeradeniyaSri Lanka
| | - Anil. W. Kalupahana
- Faculty of Veterinary Medicine and Animal ScienceDepartment of Veterinary PathobiologyUniversity of PeradeniyaPeradeniyaSri Lanka
| | - Victor P.M.G. Rutten
- Section of ImmunologyDivision Infectious Diseases and ImmunologyFaculty of Veterinary MedicineDepartment of Biomolecular Health SciencesUtrecht UniversityUtrechtThe Netherlands,Faculty of Veterinary ScienceDepartment of Veterinary Tropical DiseasesUniversity of PretoriaOnderstepoortSouth Africa
| | - Cornelis A.M. de Haan
- Section of VirologyDivision Infectious Diseases and ImmunologyFaculty of Veterinary MedicineDepartment of Biomolecular Health SciencesUtrecht UniversityUtrechtThe Netherlands
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POINT-OF-CARE AND STANDARD LABORATORY REFERENCE INTERVALS FOR COAGULATION VALUES IN ASIAN ELEPHANTS ( ELEPHAS MAXIMUS): VARIATION BY AGE CLASS, SEX, AND TIME TO CENTRIFUGATION. J Zoo Wildl Med 2022; 53:291-301. [PMID: 35758571 DOI: 10.1638/2021-0057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/24/2021] [Indexed: 11/21/2022] Open
Abstract
In Asian elephants (Elephas maximus), elephant endotheliotropic herpesvirus causes significant calf mortality. Coagulation testing may aid veterinarians in early identification and management of hemostatic disorders. This study sought to establish reference intervals for select coagulation and platelet values. Blood was collected from clinically healthy Asian elephants (n = 63) in juvenile (≤15 yr old, n = 9), adult (>15 to ≤50 yr old, n = 41), and geriatric (>50 yr old, n = 13) age classes at seven institutions in Kanchanaburi Province, Thailand. Activated clotting time (ACT) was immediately assessed with a handheld analyzer, whereas remaining blood was stored at 5°C in sodium citrate and potassium EDTA collection tubes and transported to a central laboratory. Coagulation values were assessed on an automated blood coagulation analyzer, and platelet values were assessed on a hematology analyzer. Reference intervals were established for ACT, prothrombin time, activated partial thromboplastin time, thrombin time, fibrinogen, platelet count, mean platelet volume, platelet distribution width, and plateletcrit according to the American Society for Veterinary Clinical Pathology guidelines. No significant differences were observed for any value when comparing sex and time to centrifugation. Plasma fibrinogen (P = 0.002) and platelets (P = 0.003) varied significantly by age class, with adults displaying the highest fibrinogen concentrations and geriatric individuals displaying the lowest platelet counts. The ACT kaolin cartridges resulted in high success rates (84.3% feasibility) compared with celite cartridges (4.8% feasibility). Further studies are warranted to stratify reference intervals in accordance with age class trends.
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Yang N, Bao M, Zhu B, Shen Q, Guo X, Li W, Tang R, Zhu D, Tang Y, Phalen DN, Zhang L. Elephant Endotheliotropic Herpesvirus 1, 4 and 5 in China: Occurrence in Multiple Sample Types and Implications for Wild and Captive Population Surveillance. Viruses 2022; 14:v14020411. [PMID: 35216004 PMCID: PMC8875873 DOI: 10.3390/v14020411] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 02/13/2022] [Accepted: 02/15/2022] [Indexed: 02/05/2023] Open
Abstract
Elephant endotheliotropic herpesviruses (EEHVs) are important causes of death in both captive and wild Asian elephants (Elephas maximus). Nothing is known about the prevalence of EEHVs in wild or domestic elephants in China. To determine if EEHVs are present in elephants in China, 126 wild elephants from three populations and 202 captive individuals from zoos (n = 155) and the Wild Elephant Valley (n = 47) were screened using semi-nested polymerase chain reaction assays with EEHV-redundant and EEHV1/4/5-specific primers. EEHV1B and EEHV4 were detected in samples from both wild (EEHV1B:8/126; EEHV4:2/126) and captive (EEHV1B:5/155; EEHV4:9/155) elephants, while EEHV1A (six cases) and EEHV5 (one case) were only present in the captive elephants from the Wild Elephant Valley. EEHV1 was detected in blood and trunk and oral swabs; EEHV4 was detected in trunk and oral swabs as well as feces; EEHV5 was found in trunk and oral swabs. No significant age or sex association with EEHV1A, EEHV1B, or EEHV5 positivity was observed. An age association with EEHV4 positivity was found, with all unweaned elephants being EEHV4 positive, but an association with the sex of the elephant was not observed. These findings represent the first documentation of EEHV presence in captive and wild elephants in China. These findings also document EEHV1B and EEHV4 shedding in feces and demonstrate the utility of fecal screening as a tool for investigating EEHV4 infection in wild populations of elephants. It is recommended that EEHV testing be included in surveillance programs for captive and wild elephants in China.
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Affiliation(s)
- Nian Yang
- Key Laboratory for Biodiversity and Ecological Engineering of Ministry of Education, Department of Ecology, College of Life Sciences, Beijing Normal University, Beijing 100875, China; (N.Y.); (B.Z.); (R.T.); (D.Z.); (Y.T.)
| | - Mingwei Bao
- Wild Elephant Valley, Jinghong 666100, China;
| | - Biru Zhu
- Key Laboratory for Biodiversity and Ecological Engineering of Ministry of Education, Department of Ecology, College of Life Sciences, Beijing Normal University, Beijing 100875, China; (N.Y.); (B.Z.); (R.T.); (D.Z.); (Y.T.)
| | - Qingzhong Shen
- Ecotourism Management Institute of Yunnan Xishuangbanna National Nature Reserve, Jinghong 666100, China;
| | - Xianming Guo
- Research Institute of Xishuangbanna National Nature Reserve, Jinghong 666100, China;
| | - Wenwen Li
- Key Laboratory of Coastal Science and Integrated Management, First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, China;
| | - Ruchun Tang
- Key Laboratory for Biodiversity and Ecological Engineering of Ministry of Education, Department of Ecology, College of Life Sciences, Beijing Normal University, Beijing 100875, China; (N.Y.); (B.Z.); (R.T.); (D.Z.); (Y.T.)
| | - Di Zhu
- Key Laboratory for Biodiversity and Ecological Engineering of Ministry of Education, Department of Ecology, College of Life Sciences, Beijing Normal University, Beijing 100875, China; (N.Y.); (B.Z.); (R.T.); (D.Z.); (Y.T.)
| | - Yinpu Tang
- Key Laboratory for Biodiversity and Ecological Engineering of Ministry of Education, Department of Ecology, College of Life Sciences, Beijing Normal University, Beijing 100875, China; (N.Y.); (B.Z.); (R.T.); (D.Z.); (Y.T.)
| | - David N. Phalen
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, Sydney, NSW 2006, Australia
- Schubot Exotic Bird Health Center, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, 701 Farm to Market 2818 Service Road, College Station, TX 77840, USA
- Correspondence: (D.N.P.); (L.Z.)
| | - Li Zhang
- Key Laboratory for Biodiversity and Ecological Engineering of Ministry of Education, Department of Ecology, College of Life Sciences, Beijing Normal University, Beijing 100875, China; (N.Y.); (B.Z.); (R.T.); (D.Z.); (Y.T.)
- Correspondence: (D.N.P.); (L.Z.)
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Costa T, Rocchigiani G, Zendri F, Drake G, Lopez J, Chantrey J, Ricci E. Elephant Endotheliotropic Herpesvirus 4 and Clostridium perfringens Type C Fatal Co-Infection in an Adult Asian Elephant (Elephas maximus). Animals (Basel) 2022; 12:ani12030349. [PMID: 35158672 PMCID: PMC8833544 DOI: 10.3390/ani12030349] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 01/24/2022] [Accepted: 01/28/2022] [Indexed: 01/25/2023] Open
Abstract
Elephant endotheliotropic herpesvirus hemorrhagic disease (EEHV-HD) is an acute, often fatal, multisystemic hemorrhagic disease and one of the most significant causes of mortality of Asian elephants in captivity. Most fatal cases of EEHV-HD are associated with EEHV1A and EEHV1B in juveniles. This case report describes the clinical and pathological features of a fatal co-infection of Clostridium perfringens type C and EEHV-HD, caused by EEHV4, in an adult female Asian elephant. Although fatal clostridial enterotoxemia has been occasionally reported in elephants, this report highlights the importance of having both EEHV-HD and clostridial enterotoxemia as potential differential diagnoses in cases of widespread tissue necrosis and internal hemorrhage in elephants, regardless of the animal age group, due to their macroscopic similarities, frequent co-occurrence and cumulative morbid potential.
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Affiliation(s)
- Taiana Costa
- Department of Veterinary Anatomy, Physiology and Pathology, Institute of Infection, Veterinary and Ecological Sciences, Leahurst Campus, University of Liverpool, Chester High Road, Neston CH64 7TE, UK; (T.C.); (G.R.); (F.Z.); (J.C.)
| | - Guido Rocchigiani
- Department of Veterinary Anatomy, Physiology and Pathology, Institute of Infection, Veterinary and Ecological Sciences, Leahurst Campus, University of Liverpool, Chester High Road, Neston CH64 7TE, UK; (T.C.); (G.R.); (F.Z.); (J.C.)
| | - Flavia Zendri
- Department of Veterinary Anatomy, Physiology and Pathology, Institute of Infection, Veterinary and Ecological Sciences, Leahurst Campus, University of Liverpool, Chester High Road, Neston CH64 7TE, UK; (T.C.); (G.R.); (F.Z.); (J.C.)
| | - Gabby Drake
- Chester Zoo, Upton-by-Chester, Cheshire CH2 1LH, UK; (G.D.); (J.L.)
| | - Javier Lopez
- Chester Zoo, Upton-by-Chester, Cheshire CH2 1LH, UK; (G.D.); (J.L.)
| | - Julian Chantrey
- Department of Veterinary Anatomy, Physiology and Pathology, Institute of Infection, Veterinary and Ecological Sciences, Leahurst Campus, University of Liverpool, Chester High Road, Neston CH64 7TE, UK; (T.C.); (G.R.); (F.Z.); (J.C.)
| | - Emanuele Ricci
- Department of Veterinary Anatomy, Physiology and Pathology, Institute of Infection, Veterinary and Ecological Sciences, Leahurst Campus, University of Liverpool, Chester High Road, Neston CH64 7TE, UK; (T.C.); (G.R.); (F.Z.); (J.C.)
- Correspondence:
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Effects of between and within Herd Moves on Elephant Endotheliotropic Herpesvirus (EEHV) Recrudescence and Shedding in Captive Asian Elephants (Elephas maximus). Viruses 2022; 14:v14020229. [PMID: 35215824 PMCID: PMC8877707 DOI: 10.3390/v14020229] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/18/2022] [Accepted: 01/18/2022] [Indexed: 02/01/2023] Open
Abstract
Haemorrhagic disease associated with elephant endotheliotropic herpesvirus (Elephantid herpesvirus, EEHV) infections is the leading cause of death for Asian elephant (Elephas maximus) calves. This study assessed the effect of captive herd management on EEHV shedding, as evidence of latent infection reactivation, focusing on: (1) the influence of social change on the odds of recrudescence; (2) the respective effects of between and within herd moves; and (3) characteristics of recrudescent viral shedding. Trunk and conjunctival swabs (n = 165) were obtained from six elephants at an EAZA-accredited zoo, collected during a period of social stability, and at times of social change. Longitudinal sampling took place at times of moving two bulls out of the collection and one new bull into an adjacent enclosure to the cow herd (between herd moves), and during a period of mixing this new bull with the cow herd to facilitate mating (within herd moves). Quantitative PCR was employed to detect EEHV 1a/b, 4a/b, and EF–1–α (housekeeping gene). Generalised estimating equations determined EEHV recrudescence odds ratios (OR) and relative viral DNA load. Sixteen EEHV 1a/b shedding events occurred, but no EEHV 4a/b was detected. All management-derived social changes promoted recrudescence (social change OR = 3.27, 95% CI = 0.412–26, p = 0.262; and between herd moves OR = 1.6, 95% CI = 0.178−14.4, p = 0.675), though within herd movements posed the most significant increase of EEHV reactivation odds (OR = 6.86, 95% CI = 0.823−57.1, p = 0.075) and demonstrated the strongest relative influence (post hoc Tukey test p = 0.0425). Shedding onset and magnitude ranged from six to 54 days and from 3.59 to 11.09 ΔCts. Differing challenges are associated with between and within herd movements, which can promote recrudescence and should be considered an exposure risk to naïve elephants.
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10
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Pharmacokinetics and analytical determination of acyclovir in Asian elephant calves ( Elephas maximus). Vet Anim Sci 2022; 15:100227. [PMID: 35024493 PMCID: PMC8724961 DOI: 10.1016/j.vas.2021.100227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 12/09/2021] [Accepted: 12/22/2021] [Indexed: 12/04/2022] Open
Abstract
Pharmacokinetic and bioavailability data of acyclovir following intravenous and oral administration are reported for Asian elephant calves. Data represent the first comprehensive LC-MS/MS analysis of plasma acyclovir concentrations after i.v. and oral administration in elephants.
A therapeutic regimen that includes antiviral drugs is critical for the survival of Asian elephant (Elephas maximus) calves infected with elephant endotheliotropic herpesvirus hemorrhagic disease (EEHV-HD), with acyclovir showing considerable promise. The purpose of this study was to determine the pharmacokinetics and bioavailability of acyclovir following intravenous (IV) and oral (PO) administration in Asian elephants. A single dose of acyclovir (15 mg/kg, IV or 45 mg/kg, PO) was administered to four healthy elephant calves, with a minimum 2-week washout period between treatments. Serial plasma samples were collected after each injection for acyclovir analysis using a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) technique. Maximum plasma acyclovir concentrations were 27.02 ± 6.79 µg/mL at 0.94 ± 0.31 h after IV administration, and 1.45 ± 0.20 µg/mL at 3.00 ± 0.70 h after PO administration. The half-life of the elimination phase (T1/2) was 5.84 ± 0.74 and 8.74 ± 2.47 h after IV and PO administration, respectively. After IV administration, acyclovir concentrations were higher than the half-maximal inhibitory concentration (IC50) of those found for herpes simplex virus (HSV) 1 and 2 in humans, and equid alpha herpesvirus-1 (EHV-1) for at least 12 h. By contrast, the bioavailability of oral administration was low, only 6.03 ± 0.87%, so higher doses by that route likely are needed to be effective. Due to the high concentration of plasma acyclovir after IV administration, the dose may need to be adjusted to prevent any negative side effects.
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Key Words
- %CV, Mean precision
- AUC0-inf, Total area under the plasma concentration-time curve from time zero to infinity
- AUC0-t, Total area under the plasma concentration-time curve from time 0–48h
- Acyclovir
- Asian elephant
- Bioavailability
- Cl, Total clearance
- Cmax, Peak plasma concentration
- EEHV, Elephantendotheliotropic herpesviruses
- EEHV-HD, Elephant endotheliotropic herpesvirus hemorrhagic disease
- EHV, Equid alphaherpesvirus
- Elephant endotheliotropic herpesvirus (EEHV)
- F, Bioavailability
- HSV, Herpes simplex virus
- IV, Intravenous administration
- Kel, Elimination rate constant
- LC-MS/MS, Liquid chromatography-tandem mass spectrometry
- LLOQ, Lower limit of quantitation
- MAT, Mean absorption time
- MRM, Multiple reaction monitoring
- MRT, Mean residence time
- PO, Oral administration
- Pharmacokinetics
- QC, Quality control
- S/N, Signal to noise ratio
- T1/2, Elimination half-life
- Tmax, Time to reach peak plasma
- Vd(ss), Steady-state volume of distribution
- m/z, Mass-to-charge ratio
- r2, Coefficients of determination
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11
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Patterns of serum immune biomarkers during elephant endotheliotropic herpesvirus viremia in Asian and African elephants. PLoS One 2021; 16:e0252175. [PMID: 34793450 PMCID: PMC8601435 DOI: 10.1371/journal.pone.0252175] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Accepted: 11/02/2021] [Indexed: 12/23/2022] Open
Abstract
Hemorrhagic disease (HD) caused by a group of elephant endotheliotropic herpesviruses (EEHV) is one of the leading causes of death for young elephants in human care. These viruses are widespread and typically persist latently in adult elephants with no negative effects; however, in juvenile Asian and more recently young African elephants, the onset of disease can be rapid and the mortality rate high. Measuring biomarkers associated with the immune response could be beneficial to understanding underlying disease processes, as well as the management of infection and HD. The goal of this study was to measure acute phase proteins and cytokines in serum collected from elephants infected with EEHV (13 Asian and 1 African) and compare concentrations according to presence, severity and outcome of disease. Serum amyloid A (SAA) and haptoglobin (HP) were higher in elephants with EEHV viremia than those without; concentrations increased with increasing viral load, and were higher in fatal cases compared to those that survived. In Asian elephants, SAA was also higher during EEHV1 viremia compared to EEHV5. Cytokine concentrations were typically low, and no statistical differences existed between groups. However, in individuals with detectable levels, longitudinal profiles indicated changes in tumor necrosis factor alpha (TNF-α) and interleukin-2 (IL-2) that may reflect an immune response to EEHV infection. However, the overall low concentrations detected using previously validated assays do not support the presence of a 'cytokine storm' and suggest more work is needed to understand if sub-optimal immune responses could be involved in disease progression. These results highlight the potential benefit of measuring circulating biomarker concentrations, such as APPs and cytokines, to improve our understanding of EEHV viremia and HD, assist with monitoring the progression of disease and determining the impact of interventions.
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12
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Jesus SA, Doherr MG, Hildebrandt TB. Elephant Endotheliotropic Herpesvirus Impact in the European Asian Elephant ( Elephas maximus) Population: Are Hereditability and Zoo-Associated Factors Linked with Mortality? Animals (Basel) 2021; 11:ani11102816. [PMID: 34679837 PMCID: PMC8532781 DOI: 10.3390/ani11102816] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 09/20/2021] [Accepted: 09/23/2021] [Indexed: 11/16/2022] Open
Abstract
EEHV is a ubiquitous virus, which most likely has co-evolved with elephants and is shed by healthy individuals and maintained in the herds. Yet, the factors determining calf susceptibility to the virus remain unknown. Here, we explored the impact of EEHV-HD in the European captive Asian elephant population in a retrospective statistical study spanning the last 35 years. We show that EEHV-HD was implicated in more than half of all deaths recorded in calves older than one months old. Moreover, the median age across EEHV-HD fatalities was significantly lower compared to other death causes. Finally, we investigated if heredity and zoo-associated factors could be linked to a higher susceptibility of calves to this disease. We used a univariable logistic regression model to evaluate if either fathers, mothers, or zoos could, separately, be considered as risk factors to the development of the disease. Afterwards, we used a two multivariable model, combining: (1) fathers and zoos, and (2) mothers and zoos. Overall, we found that two fathers, one mother, and four zoos had three or more times higher risk of their calves becoming sick when compared to all others, pointing us to the presence of a management or environmental element, which can have paternal and maternal influence and leads to calf susceptibility or resistance to EEHV-HD.
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Affiliation(s)
- Sónia A. Jesus
- Department of Reproduction Management, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Straße 17, 10315 Berlin, Germany;
- Correspondence:
| | - Marcus G. Doherr
- Institute for Veterinary Epidemiology and Biostatistics, Freie Universität, Königsweg 67, 14163 Berlin, Germany;
| | - Thomas B. Hildebrandt
- Department of Reproduction Management, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Straße 17, 10315 Berlin, Germany;
- Faculty of Veterinary Medicine, Freie Universität, Oertzenweg 19 b, 14163 Berlin, Germany
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13
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Yun Y, Sripiboon S, Pringproa K, Chuammitri P, Punyapornwithaya V, Boonprasert K, Tankaew P, Angkawanish T, Namwongprom K, Arjkumpa O, Brown JL, Thitaram C. Clinical characteristics of elephant endotheliotropic herpesvirus (EEHV) cases in Asian elephants ( Elephas maximus) in Thailand during 2006-2019. Vet Q 2021; 41:268-279. [PMID: 34511026 PMCID: PMC8475116 DOI: 10.1080/01652176.2021.1980633] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Background Elephant endotheliotropic herpesvirus causes a hemorrhagic disease (EEHV-HD) that is a major cause of death in juvenile Asian elephants with EEHV1 and EEHV4 being the most prevalent. Aim To perform a retrospective clinical data analysis. Methods Records of a total of 103 cases in Thailand confirmed by polymerase chain reaction (PCR) on blood and/or tissue samples. Results The severity of clinical signs varied among EEHV subtypes. EEHV1A was the most prevalent with 58%, followed by EEHV4 with 34%, EEHV1B with 5.8% and EEHV1&4 co-infection with 1.9%. Overall case fatality rate was 66%. When compared among subtypes, 100% case fatality rate was associated with EEHV1&4 co-infection, 83% with EEHV1B, 75% with EEHV1A, and the lowest at 40% for EEHV4. Calves 2- to 4-year old were in the highest age risk group and exhibited more severe clinical signs with the highest mortality. Majority of cases were found in weaned or trained claves and higher number of cases were observed in rainy season. A gender predilection could not be demonstrated. Severely affected elephants presented with thrombocytopenia, depletion of monocytes, lymphocytes and heterophils, a monocyte:heterophil (M:H) ratio lower than 2.37, hypoproteinemia (both albumin and globulin), severe grade of heterophil toxicity, and low red blood cell counts and pack cell volumes. Survival was not affected by antiviral drug treatment in the severely compromised animals. Conclusion Early detection by laboratory testing and aggressive application of therapies comprising of supportive and anti-viral treatment can improve survival outcomes of this disease.
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Affiliation(s)
- Yaoprapa Yun
- Faculty of Veterinary Medicine, Center of Elephant and Wildlife Research, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand.,Graduate Program in Veterinary Science, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Supaphen Sripiboon
- Faculty of Veterinary Medicine, Department of Large Animal and Wildlife Clinical Sciences, Kasetsart University (FVM-KU), Kamphaeng Saen Campus, Nakornpathom, Thailand
| | - Kidsadagon Pringproa
- Faculty of Veterinary Medicine, Department of Veterinary Biosciences and Public Health, Chiang Mai University, Chiang Mai, Thailand
| | - Phongsakorn Chuammitri
- Faculty of Veterinary Medicine, Department of Veterinary Biosciences and Public Health, Chiang Mai University, Chiang Mai, Thailand
| | - Veerasak Punyapornwithaya
- Faculty of Veterinary Medicine, Veterinary Public Health and Food Safety Centre for Asia Pacific, Chiang Mai University, Chiang Mai, Thailand
| | - Khajohnpat Boonprasert
- Faculty of Veterinary Medicine, Center of Elephant and Wildlife Research, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand
| | - Pallop Tankaew
- Faculty of Veterinary Medicine, Center of Elephant and Wildlife Research, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand
| | - Taweepoke Angkawanish
- Elephant Hospital, National Elephant Institute (NEI), Forest Industry Organization, Lampang, Thailand
| | - Kittikul Namwongprom
- Elephant Hospital, National Elephant Institute (NEI), Forest Industry Organization, Lampang, Thailand
| | - Orapun Arjkumpa
- Phra Nakhon Si Ayutthaya Provincial Livestock Office, Phra Nakhon Si Ayutthaya Province, Thailand
| | - Janine L Brown
- Faculty of Veterinary Medicine, Center of Elephant and Wildlife Research, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand.,Center for Species Survival, Smithsonian Conservation Biology Institute (SCBI), Front Royal, VA, USA
| | - Chatchote Thitaram
- Faculty of Veterinary Medicine, Center of Elephant and Wildlife Research, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand.,Department of Companion Animal and Wildlife Clinics, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
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14
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Common SM, Yun Y, Silva-Fletcher A, Thitaram C, Janyamethakul T, Khammesri S, Molenaar FM. Developing a non-invasive method of detecting elephant endotheliotropic herpesvirus infections using faecal samples. Vet Rec 2021; 190:e833. [PMID: 34472109 DOI: 10.1002/vetr.833] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 06/07/2021] [Accepted: 07/27/2021] [Indexed: 02/06/2023]
Abstract
BACKGROUND Elephant endotheliotropic herpesvirus (EEHV)-associated haemorrhagic disease (EEHV-HD) is a leading cause of death in Asian elephant calves across the world. Cases of EEHV-HD have been detected in free-living calves through post-mortem examination (PME) indicating the presence of the virus in the wild. In the absence of a non-invasive sampling method, little research into free-living populations has been possible. This study aimed to provide evidence that faeces can be used as a non-invasive sampling method for the detection of EEHV excretion using quantitative polymerase chain reaction. METHODS Serial saliva swabs and faecal samples were taken from five captive Asian elephants in Thailand over 12 weeks. To ensure the presence of detectable elephant DNA within the sample, qPCR was run for amplification of the Asian elephant tumour necrosis factor (TNF-α) gene, EEHV1 and EEHV4. RESULTS Of 28 sample pairs, seven saliva samples were positive for EEHV, of which two had paired positive faecal samples. CONCLUSIONS This study presents the first evidence that EEHV is excreted in faeces at detectable levels. This method may in future be used for improved understanding of the epidemiology of EEHV in free-living elephant populations, as well as detection of EEHV excretion in captive herds.
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Affiliation(s)
- Sophie M Common
- Institute of Zoology, Zoological Society of London, Regents Park, London, NW8 7LS, UK.,The Royal Veterinary College, Hatfield, Hertfordshire, UK
| | - Yaoprapa Yun
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand
| | | | - Chatchote Thitaram
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand
| | | | - Siripat Khammesri
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University (FVM-CMU), Chiang Mai, Thailand
| | - Fieke M Molenaar
- Whipsnade Zoo, Zoological Society of London, Dunstable, Bedfordshire, UK
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15
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Boonprasert K, Yun Y, Kosaruk W, Towiboon P, Tankaew P, Punyapornwithaya V, Janyamathakul T, Muanghong P, Brown JL, Thitaram C, Somgird C. A Longitudinal Study of Hematology and Stress Biomarker Profiles in Young Asian Elephants ( Elephas Maximus) in Relation to Elephant Endotheliotropic Herpesvirus (EEHV) in Thailand. Animals (Basel) 2021; 11:ani11092530. [PMID: 34573496 PMCID: PMC8471699 DOI: 10.3390/ani11092530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 08/22/2021] [Accepted: 08/23/2021] [Indexed: 12/14/2022] Open
Abstract
Simple Summary A change in hematology profiles is one indicator of EEHV infection before clinical signs appear; however, to be effective, individual baselines and age-matched reference values are needed. A longitudinal investigation of viremia, hematology values, and stress biomarkers was performed in three non-EEHV and six prior infected EEHV calves to better understand EEHV-HD-associated factors. Blood, saliva, and feces were collected for 1 year for analysis of complete blood count (CBC), viral load, glucocorticoids (GCs), and Immunoglobulin A (IgA). Results did not differ between the groups, except for one elephant that presented with EEHV-HD during the study and exhibited high viremia, altered hematology profiles, and decreased stress biomarker concentrations. Thus, as in other studies, hematology changes were associated with EEHV infection, while preliminary data in one calf suggests that stress-response measures might also be informative and warrant further investigation. Abstract Elephant endotheliotropic herpesvirus hemorrhagic disease (EEHV-HD) is a virulent disease that causes severe hemorrhage and sudden death in Asian elephant calves. A change in hematology profiles is one indicator of infection before clinical signs appear; however, to be effective, individual baselines and age-matched reference values are needed. Stress has been speculated to be a factor in clinical EEHV cases, but relationships have not been demonstrated empirically. This study evaluated blood hematology and several stress response markers—salivary cortisol, fecal glucocorticoid metabolites (FGM), salivary Immunoglobulin A (SIgA), and fecal IgA (FIgA) in samples collected for 1 year from three healthy calves with no EEHV history (non-EEHV), and six that had previously been infected, developed clinical signs and survived (prior-EEHV). Hematology values between non-EEHV and prior-EEHV elephants were not different and within published reference ranges. Concentrations of salivary cortisol, FGM, SIgA, and FIgA also were variable and showed seasonal differences, but no relationships to prior EEHV status. One of the prior EEHV calves became re-infected, developed hemorrhagic disease (HD), and died during the study period. That calf exhibited lymphocytopenia, monocytopenia, and thrombocytopenia. Additionally, all stress biomarker concentrations were lower in the 12 days before viremia was observed. Thus, as in other studies, changes in hematology occur with EEHV infection, while preliminary data in one calf suggests that stress-response measures might also be informative and should be studied further.
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Affiliation(s)
- Khajohnpat Boonprasert
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; (K.B.); (Y.Y.); (W.K.); (P.T.); (P.T.); (J.L.B.); (C.T.)
| | - Yaoprapa Yun
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; (K.B.); (Y.Y.); (W.K.); (P.T.); (P.T.); (J.L.B.); (C.T.)
| | - Worapong Kosaruk
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; (K.B.); (Y.Y.); (W.K.); (P.T.); (P.T.); (J.L.B.); (C.T.)
| | - Patcharapa Towiboon
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; (K.B.); (Y.Y.); (W.K.); (P.T.); (P.T.); (J.L.B.); (C.T.)
| | - Pallop Tankaew
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; (K.B.); (Y.Y.); (W.K.); (P.T.); (P.T.); (J.L.B.); (C.T.)
| | - Veerasak Punyapornwithaya
- Department of Food Animal Clinic, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand;
- Veterinary Public Health Centre and Food Safety for Asia Pacific (VPHCAP), Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
| | | | - Panida Muanghong
- Mae Taeng Elephant Park and Clinic, Mae Thang, Chiang Mai 50150, Thailand;
| | - Janine L. Brown
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; (K.B.); (Y.Y.); (W.K.); (P.T.); (P.T.); (J.L.B.); (C.T.)
- Center for Species Survival, Smithsonian Conservation Biology Institute, Front Royal, VA 22630, USA
| | - Chatchote Thitaram
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; (K.B.); (Y.Y.); (W.K.); (P.T.); (P.T.); (J.L.B.); (C.T.)
- Department of Companion Animal and Wildlife Clinics, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
| | - Chaleamchat Somgird
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; (K.B.); (Y.Y.); (W.K.); (P.T.); (P.T.); (J.L.B.); (C.T.)
- Department of Companion Animal and Wildlife Clinics, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand
- Correspondence: ; Tel.: +66-53-948015
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16
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Perrin KL, Kristensen AT, Bertelsen MF, Denk D. Retrospective review of 27 European cases of fatal elephant endotheliotropic herpesvirus-haemorrhagic disease reveals evidence of disseminated intravascular coagulation. Sci Rep 2021; 11:14173. [PMID: 34238966 PMCID: PMC8266883 DOI: 10.1038/s41598-021-93478-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 06/25/2021] [Indexed: 02/06/2023] Open
Abstract
Elephant endotheliotropic herpesvirus haemorrhagic disease (EEHV-HD) is widely acknowledged as the most common cause of mortality in young Asian elephants (Elephas maximus) in captivity. The objective of the current study was to perform a blinded, retrospective pathology review of European EEHV-HD fatalities, constituting the largest systematic assessment of EEHV-HD pathology to date. Findings between viral genotypes were compared with the aim to investigate if disseminated intravascular coagulation (DIC) could be substantiated as a significant complicating factor, thereby increasing the understanding of disease pathophysiology. Immunohistochemical staining confirmed endothelial cell (EC) damage and the presence of EC intranuclear inclusion bodies, demonstrating a direct viral cytopathic effect. Microthrombi were observed in 63% of cases in several organs, including lungs, which, together with widespread haemorrhage and thrombocytopenia reported in EEHV-HD case reports, supports the presence of overt DIC as a serious haemostatic complication of active EEHV infection. Death was attributed to widespread vascular damage with multi-organ dysfunction, including severe acute myocardial haemorrhage and subsequent cardiac failure. Systemic inflammation observed in the absence of bacterial infection may be caused by cytokine release syndrome. Findings reinforce the necessity to investigate cytokine responses and haemostatic status during symptomatic and asymptomatic EEHV viraemia, to potentially support the use of anti-inflammatory treatment in conjunction with anti-viral therapy and cardiovascular support.
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Affiliation(s)
- K L Perrin
- Center for Zoo and Wild Animal Health, Copenhagen Zoo, Roskildevej 38, 2000, Frederiksberg, Denmark.
- The Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlægevej 16, 1870, Frederiksberg, Denmark.
| | - A T Kristensen
- The Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlægevej 16, 1870, Frederiksberg, Denmark
| | - M F Bertelsen
- Center for Zoo and Wild Animal Health, Copenhagen Zoo, Roskildevej 38, 2000, Frederiksberg, Denmark
| | - D Denk
- International Zoo Veterinary Group, Station House, Parkwood Street, Keighley, BD21 4NQ, UK
- Institute for Animal Pathology, Ludwig-Maximilians-University, Veterinärstr. 13, 80539, Munich, Germany
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17
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Hoornweg TE, Schaftenaar W, Maurer G, van den Doel PB, Molenaar FM, Chamouard-Galante A, Vercammen F, Rutten VPMG, de Haan CAM. Elephant Endotheliotropic Herpesvirus Is Omnipresent in Elephants in European Zoos and an Asian Elephant Range Country. Viruses 2021; 13:v13020283. [PMID: 33670367 PMCID: PMC7917619 DOI: 10.3390/v13020283] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/05/2021] [Accepted: 02/06/2021] [Indexed: 11/16/2022] Open
Abstract
Elephant endotheliotropic herpesviruses (EEHVs) may cause acute, often lethal, hemorrhagic disease (EEHV-HD) in young elephants. Prevalence of EEHV in different elephant populations is still largely unknown. In order to improve diagnostic tools for the detection of EEHV infections and to obtain insight into its spread among elephants, we developed novel ELISAs based on EEHV1A gB and gH/gL. Performance of the ELISAs was assessed using sera from 41 European zoo elephants and 69 semi-captive elephants from Laos, one of the Asian elephant range countries. Sera from all (sub)adult animals tested (≥5 years of age) showed high reactivity with both gB and gH/gL, indicating that EEHV prevalence has been highly underestimated so far. Reactivity towards the antigens was generally lower for sera of juvenile animals (1 > 5 years). Only one (juvenile) animal, which was sampled directly after succumbing to EEHV-HD, was found to be seronegative for EEHV. The two other EEHV-HD cases tested showed low antibody levels, suggesting that all three cases died upon a primary EEHV infection. In conclusion, our study suggests that essentially all (semi-)captive (sub)adult elephants in European zoos and in Laos carry EEHV, and that young elephants with low antibody levels are at risk of dying from EEHV-HD.
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Affiliation(s)
- Tabitha E Hoornweg
- Section Virology, Division Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, The Netherlands
- Section Immunology, Division Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, The Netherlands
| | - Willem Schaftenaar
- Veterinary Advisor EAZA Elephant TAG, Rotterdam Zoo, 3041 JG Rotterdam, The Netherlands
| | - Gilles Maurer
- Center for Functional and Evolutionary Ecology (CEFE), Univ. Montpellier, CNRS, EPHE, IRD, Univ. Paul Valéry Montpellier 3, 34090 Montpellier, France
- Zooparc de Beauval & Beauval Nature, 41110 Saint-Aignan, France
| | | | - Fieke M Molenaar
- Zoological Society of London, ZSL Whipsnade Zoo, Dunstable LU6 2LF, Bedfordshire, UK
| | | | - Francis Vercammen
- Antwerp Zoo Centre for Research and Conservation, Antwerp Zoo Society, 2018 Antwerp, Belgium
| | - Victor P M G Rutten
- Section Immunology, Division Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, The Netherlands
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa
| | - Cornelis A M de Haan
- Section Virology, Division Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, The Netherlands
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Prompiram P, Wiriyarat W, Bhusri B, Paungpin W, Jairak W, Sripiboon S, Wongtawan T. The occurrence of elephant endotheliotropic herpesvirus infection in wild and captive Asian elephants in Thailand: Investigation based on viral DNA and host antibody. Vet World 2021; 14:545-550. [PMID: 33776322 PMCID: PMC7994120 DOI: 10.14202/vetworld.2021.545-550] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 01/21/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND AND AIM Elephant endotheliotropic herpesvirus (EEHV) is a serious disease, threatening the life of young elephants. Many elephants have been infected with no clinical signs and may serve as carriers spreading this disease. It is important to monitor the disease through clinical signs and molecular diagnosis. In this study we investigated the occurrence of EEHV and the efficiency of different techniques used to monitor EEHV infection in various samples and populations of Asian elephants. MATERIALS AND METHODS Blood and trunk swabs were collected from live elephants, while visceral organs (lung, digestive tract, spleen, lymph nodes, and kidney) were collected from dead elephants. EEHV was detected by polymerase chain reaction (PCR) in whole blood, trunk swabs, and visceral organs as samples, while elephant anti-EEHV immunoglobulin G (IgG) in serum was detected by enzyme-linked immunosorbent assay (ELISA). A total of 162 samples were analyzed in this study: 129 from healthy, 26 from dead, and 7 from sick elephants. RESULTS The present study showed that the overall incidence of EEHV was 40.1% (n=65/162). Approximately 46.2% (n=12/26) and 85.7% (n=6/7) of dead and sick elephants were positive for EEHV by PCR, respectively. All sick elephants that were young and affected by EEHV clinical disease tested negative for the IgG antibody ELISA, suggesting primary EEHV infection in this group. In addition, 2.3% (n=3/129) of subclinical infections were detected using PCR, and trunk swab samples showed slightly higher sensitivity (5.3%, n=2/38) to detect EEHV than whole blood (1.2%, n=1/84). As many as, 48.4% (n=44/91) of healthy elephants were EEHV seropositive (ELISA-positive), suggesting that many elephants in Thailand had previously been infected. Overall, 30% of dead wild elephants had been infected with EEHV (n=3/10). Moreover, statistical analysis revealed no significant differences in the EEHV detection rate between different age groups or sexes (p>0.05). CONCLUSION PCR is better than ELISA to detect EEHV active infection in dead/sick elephants and to monitor EEHV in young elephants. ELISA is suitable for detecting previous EEHV infection and carriers, particularly adults. Theoretically, we could use both PCR and ELISA to increase the sensitivity of testing, along with observing abnormal behavior to efficiently monitor this disease. Identification of EEHV carriers within elephant populations is important to prevent transmission to healthy individuals, especially young elephants with high mortality from EEHV. This is the first report from Thailand regarding EEHV infection in wild elephants, showing the importance of preventing disease transmission between captive and wild elephants.
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Affiliation(s)
- Phirom Prompiram
- The Monitoring and Surveillance Centre for Zoonotic Diseases in Wildlife and Exotic Animals, Faculty of Veterinary Science, Mahidol University, Salaya, Phutthamonthon, Nakhon Pathom, 73170, Thailand
- Laboratory of Veterinary Biomedicine, Faculty of Veterinary Science, Mahidol University, Salaya, Phutthamonthon, Nakhon Pathom, 73170, Thailand
| | - Witthawat Wiriyarat
- The Monitoring and Surveillance Centre for Zoonotic Diseases in Wildlife and Exotic Animals, Faculty of Veterinary Science, Mahidol University, Salaya, Phutthamonthon, Nakhon Pathom, 73170, Thailand
- Department of Preclinical Science, Mahidol University, Salaya, Phutthamonthon, Nakhon Pathom, 73170, Thailand
| | - Benjaporn Bhusri
- The Monitoring and Surveillance Centre for Zoonotic Diseases in Wildlife and Exotic Animals, Faculty of Veterinary Science, Mahidol University, Salaya, Phutthamonthon, Nakhon Pathom, 73170, Thailand
| | - Weena Paungpin
- The Monitoring and Surveillance Centre for Zoonotic Diseases in Wildlife and Exotic Animals, Faculty of Veterinary Science, Mahidol University, Salaya, Phutthamonthon, Nakhon Pathom, 73170, Thailand
| | - Waleemas Jairak
- Zoological Park Organization, 267 Pracharat 1 Road, Bangsue Bangkok 10800, Thailand
| | - Supaphen Sripiboon
- Department of Large Animal and Wildlife Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand
| | - Tuempong Wongtawan
- Laboratory of Veterinary Biomedicine, Faculty of Veterinary Science, Mahidol University, Salaya, Phutthamonthon, Nakhon Pathom, 73170, Thailand
- Department of Preclinical Science, Mahidol University, Salaya, Phutthamonthon, Nakhon Pathom, 73170, Thailand
- Centre of Excellence for One Health, Akkhraratchakumari Veterinary College, Walailak University, Thai Buri, Tha Sala, Nakhon Si Thammarat 80160 Thailand
- Centre of Excellence Research for Melioidosis and other Microorganism, Walailak University, Thai Buri, Tha Sala, Nakhon Si Thammarat 80160 Thailand
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Khammesri S, Mathura Y, Boonprasert K, Ampasavate C, Hongwiset D, Brown JL, Thitaram C. Successful treatment of elephant endotheliotropic herpesvirus infection in an Asian elephant (Elephas maximus) calf by oral acyclovir medication: Case report. J Vet Med Sci 2020; 83:125-129. [PMID: 33239478 PMCID: PMC7870404 DOI: 10.1292/jvms.20-0375] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Elephant endotheliotropic herpesvirus (EEHV) is a major cause of death in Asian elephant (Elephas maximus) calves. A 2-year, 11-month-old
female, captive Asian elephant presented with facial edema and a mild fever. Blood samples were collected and showed EEHV1A positivity with a high viral load by
real time PCR. Heterophil toxicity also was reported for the first time in this case. The calf was treated orally with acyclovir, 45 mg/kg tid for 28 days,
which reduced the EEHV1A viral load to undetectable levels within 9 days and the calf survived. A successful outcome with oral acyclovir administration provides
another and affordable option to treat EEHV hemorrhagic disease in Asian elephants, and one that is easier to administer in untrained calves.
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Affiliation(s)
- Siripat Khammesri
- Graduate Program in Veterinary Science, Faculty of Veterinary Medicine, Chiang Mai University, 155, Mae Hia, Muang, Chiang Mai, 50100, Thailand.,Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, 155, Mae Hia, Muang, Chiang Mai, 50100, Thailand
| | - Yaoprapa Mathura
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, 155, Mae Hia, Muang, Chiang Mai, 50100, Thailand
| | - Khajohnpat Boonprasert
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, 155, Mae Hia, Muang, Chiang Mai, 50100, Thailand
| | - Chadarat Ampasavate
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Chiang Mai University, 239, Suthep Road, Muang, Chiang Mai 50200, Thailand
| | - Darunee Hongwiset
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Chiang Mai University, 239, Suthep Road, Muang, Chiang Mai 50200, Thailand
| | - Janine L Brown
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, 155, Mae Hia, Muang, Chiang Mai, 50100, Thailand.,Center for Species Survival, Smithsonian Conservation Biology Institute, Front Royal, VA 22630, USA
| | - Chatchote Thitaram
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, 155, Mae Hia, Muang, Chiang Mai, 50100, Thailand.,Department of Companion Animal and Wildlife Clinic, Faculty of Veterinary Medicine, Chiang Mai University, 155, Mae Hia, Muang, Chiang Mai, 50100, Thailand
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20
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Drake GJ, Haycock J, Dastjerdi A, Davies H, Lopez FJ. Use of immunostimulants in the successful treatment of a clinical EEHV1A infection in an Asian elephant (
Elephas maximus
). VETERINARY RECORD CASE REPORTS 2020. [DOI: 10.1136/vetreccr-2020-001158] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Gabby J Drake
- Veterinary DepartmentChester ZooChesterCheshire West and ChesterUK
| | - Jonathan Haycock
- MVIU VirologyAnimal and Plant Health AgencyAddlestoneSurreyUK
- School of Veterinary MedicineFaculty of Health and Medical SciencesUniversity of SurreyGuildfordSurreyUK
| | - Akbar Dastjerdi
- MVIU VirologyAnimal and Plant Health AgencyAddlestoneSurreyUK
| | - Hannah Davies
- MVIU VirologyAnimal and Plant Health AgencyAddlestoneSurreyUK
- School of Veterinary MedicineFaculty of Health and Medical SciencesUniversity of SurreyGuildfordSurreyUK
| | - F Javier Lopez
- Veterinary DepartmentChester ZooChesterCheshire West and ChesterUK
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21
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Serum Health Biomarkers in African and Asian Elephants: Value Ranges and Clinical Values Indicative of the Immune Response. Animals (Basel) 2020; 10:ani10101756. [PMID: 32992555 PMCID: PMC7601509 DOI: 10.3390/ani10101756] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/18/2020] [Accepted: 09/25/2020] [Indexed: 01/07/2023] Open
Abstract
Simple Summary Biomarkers are biological molecules found in the blood or other fluids or tissues that can indicate normal or abnormal processes or disease. Developing tools to measure biomarkers that indicate immune function and establishing concentrations observed within a species is an important first step in their use for managing health and understanding disease processes. Here we report assays, observed value ranges, and concentrations during illness or injury for seven immune biomarkers measured in the serum of African and Asian elephants under human care. Concentrations were variable in both clinical and non-clinical samples, but all seven biomarkers were elevated in at least one case and most increased in response to routine vaccination in a single Asian elephant. These tools provide an exciting avenue for monitoring health status and helping diagnose and treat health problems in wildlife species, like elephants. Abstract Serum biomarkers indicative of inflammation and disease can provide useful information regarding host immune processes, responses to treatment and prognosis. The aims of this study were to assess the use of commercially available anti-equine reagents for the quantification of cytokines (tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), interleukins (IL) 2, 6, and 10) in African (Loxodonta africana, n = 125) and Asian (Elephas maximus, n = 104) elephants, and alongside previously validated anti-human reagents for acute-phase proteins (serum amyloid A and haptoglobin), calculate species-specific biomarker value ranges. In addition, we used opportunistically collected samples to investigate the concentrations of each biomarker during identified clinical cases of illness or injury, as a first step to understanding what biomarkers may be useful to managing elephant health. Immune biomarkers were each elevated above the calculated species-specific value ranges in at least one clinical case, but due to variability in both clinical and non-clinical samples, only serum amyloid A was significantly higher in clinical compared to non-clinical paired samples, with tendencies for higher TNF-α and IL-10. We also detected increased secretion of serum amyloid A and all five cytokines following routine vaccination of a single Asian elephant, indicating that these biomarkers can be beneficial for studying normal immune processes as well as pathology. This study indicates that assays developed with commercial reagents can be used to quantify health biomarkers in wildlife species and identifies several that warrant further investigation to elucidate immune responses to various pathologies.
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22
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In vivo characterization of target cells for acute elephant endotheliotropic herpesvirus (EEHV) infection in Asian elephants (Elephas maximus). Sci Rep 2020; 10:11402. [PMID: 32647124 PMCID: PMC7347588 DOI: 10.1038/s41598-020-68413-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 06/24/2020] [Indexed: 12/16/2022] Open
Abstract
Elephant endotheliotropic herpesvirus-hemorrhagic disease (EEHV-HD) is a dangerous viral infectious disease in young Asian elephants. Despite hypotheses underlying pathogenesis of the disease, it is unclear which cell types the virus targets during acute or persistent infections. This study investigated the tissues and target cells permissive for EEHV infection and replication in vivo. Rabbit polyclonal antibodies against the non-structural proteins of EEHV, DNA polymerase (EEHV DNAPol), were generated and validated. These were used to examine EEHV infection and replication in various tissues of acute EEHV-HD cases and compared to an EEHV-negative control. The results indicated that viral antigens were distributed throughout the epithelia of the alimentary tract and salivary glands, endothelia and smooth muscle cells, and monocytic lineage cells of the EEHV-infected elephants. Moreover, EEHV DNAPol proteins were also found in the bone marrow cells of the EEHV1A-HD and EEHV1A/4-HD cases. This study demonstrated for the first time the target cells that favor in vivo EEHV replication during acute infection, providing a promising foundation for investigating EEHV propagation in vitro.
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Dierenfeld ES, Han YAM, Mar KU, Aung A, Soe AT, Lummaa V, Lahdenperä M. Milk Composition of Asian Elephants ( Elephas maximus) in a Natural Environment in Myanmar during Late Lactation. Animals (Basel) 2020; 10:ani10040725. [PMID: 32331387 PMCID: PMC7222762 DOI: 10.3390/ani10040725] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 04/16/2020] [Accepted: 04/19/2020] [Indexed: 12/13/2022] Open
Abstract
The nutritional content of milk from free-living Asian elephants has not previously been reported, despite being vital for better management of captive populations. This study analyzed both milk composition and consumed plant species of Asian elephants managed in their natural environment in Myanmar. Longitudinal samples (n = 36) were obtained during both the wet and the dry season from six mature females in mid to late lactation in 2016 and 2017. Milk composition averaged 82.44% water, with 17.56% total solids containing 5.23% protein, 15.10% fat, 0.87% ash, and 0.18 µg/mL vitamin E. Solids and protein increased with lactation month. Total protein in milk was higher during the wet vs. the dry season. Observed factors linked with maternal (age, parity, size and origin) and calf traits (sex) had significant associations with milk nutrient levels. Primary forages consumed contained moderate protein and fiber. Higher dietary protein during the wet season (11-25%) compared to the dry season (6-19%) may be linked with increased milk protein observed. Our results call for further field studies of milk and diet composition, over entire seasons/lactation periods, and across maternal and calf traits, to improve feeding management, with an overall goal of maximized health and survival.
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Affiliation(s)
- Ellen S. Dierenfeld
- Ellen S. Dierenfeld, LLC, St. Louis, MO 63128, USA
- School of Animal, Rural and Environmental Sciences, Nottingham Trent University, Southwell NG25 0QF, UK
- Correspondence: ; Tel.: +1-314-717-3885
| | - Yadana A. M. Han
- Department of Medical Research (Pyin-Oo-Lwin Branch), Pyin-Oo-Lwin 05081, Myanmar;
- Department of Physiology and Biochemistry, University of Veterinary Science, Yezin 05282, Myanmar;
| | - Khyne U. Mar
- Veterinarians International, One Penn Plaza, Suite 6337, New York, NY 10119, USA;
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - Aung Aung
- Department of Physiology and Biochemistry, University of Veterinary Science, Yezin 05282, Myanmar;
| | - Aung Thura Soe
- Extraction Department, Magway Region, Myanma Timber Enterprise, Magwe 0411, Myanmar;
| | - Virpi Lummaa
- Department of Biology, University of Turku, 20014 Turku, Finland;
| | - Mirkka Lahdenperä
- Department of Public Health, University of Turku and Turku University Hospital, 20520 Turku, Finland;
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24
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Abstract
Understanding factors preventing populations of endangered species from being self-sustaining is vital for successful conservation, but we often lack sufficient data to understand dynamics. The global Asian elephant population has halved since the 1950s, however >25% currently live in captivity and effective management is essential to maintain viable populations. Here, we study the largest semi-captive Asian elephant population, those of the Myanma timber industry (~20% global captive population), whose population growth is heavily limited by juvenile mortality. We assess factors associated with increased mortality of calves aged 4.0–5.5 years, the taming age in Myanmar, a process affecting ~15,000 captive elephants to varying degrees worldwide. Using longitudinal survival data of 1,947 taming-aged calves spanning 43 years, we showed that calf mortality risk increased by >50% at the taming age of four, a peak not seen in previous studies on wild African elephants. Calves tamed at younger ages experienced higher mortality risk, as did calves with less experienced mothers. Taming-age survival greatly improved after 2000, tripling since the 1970’s. Management should focus on reducing risks faced by vulnerable individuals such as young and first-born calves to further improve survival. Changes associated with reduced mortality here are important targets for improving the sustainability of captive populations.
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25
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Sripiboon S, Ditcham W, Vaughan-Higgins R, Jackson B, Robertson I, Thitaram C, Angkawanish T, Phatthanakunanan S, Lertwatcharasarakul P, Warren K. Subclinical infection of captive Asian elephants (Elephas maximus) in Thailand with elephant endotheliotropic herpesvirus. Arch Virol 2019; 165:397-401. [PMID: 31784909 DOI: 10.1007/s00705-019-04469-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 10/16/2019] [Indexed: 11/30/2022]
Abstract
Elephant endotheliotropic herpesvirus (EEHV) infection is a conservation threat to the endangered Asian elephant (Elephas maximus), causing fatal hemorrhagic disease in juvenile elephants throughout the world, including Thailand. This study revealed a subclinical EEHV1 infection rate of 5.5% in healthy captive Asian elephants in Thailand (n = 362). The virus was detected in all age classes above one year old, in both sexes, and across the country - even in facilities with no history of hemorrhagic disease (EEHV HD). Subclinical EEHV infection in Thailand urgently requires proper health management.
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Affiliation(s)
- Supaphen Sripiboon
- College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, Australia. .,Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom, Thailand.
| | - William Ditcham
- College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, Australia
| | - Rebecca Vaughan-Higgins
- College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, Australia
| | - Bethany Jackson
- College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, Australia
| | - Ian Robertson
- College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, Australia
| | - Chatchote Thitaram
- Center of Elephant and Wildlife Research, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand
| | | | - Sakuna Phatthanakunanan
- Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom, Thailand
| | | | - Kristin Warren
- College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Murdoch, Australia
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