Into the large ears: otitis externa associated with nematodes, mites, and bacteria in Asian elephants (Elephas maximus)
Abstract Background The Asian elephant (Elephas maximus), which is an endangered species, harbors several parasites. Among the ectoparasites that it harbors, ear mites of the genus Loxanoetus have the potential to cause external otitis, an inflammation that may also be associated with the presence o...
| Main Authors: | , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
BMC
2023-03-01
|
| Series: | Parasites & Vectors |
| Subjects: | |
| Online Access: | https://doi.org/10.1186/s13071-023-05708-1 |
| _version_ | 1827985019083161600 |
|---|---|
| author | Marcos Antonio Bezerra-Santos Jairo Alfonso Mendoza-Roldan Peter M. DiGeronimo Erica Ward Bruce Noden Francesca De Luca Elena Fanelli Domenico Valenzano Riccardo Paolo Lia Domenico Otranto |
| author_facet | Marcos Antonio Bezerra-Santos Jairo Alfonso Mendoza-Roldan Peter M. DiGeronimo Erica Ward Bruce Noden Francesca De Luca Elena Fanelli Domenico Valenzano Riccardo Paolo Lia Domenico Otranto |
| author_sort | Marcos Antonio Bezerra-Santos |
| collection | DOAJ |
| description | Abstract Background The Asian elephant (Elephas maximus), which is an endangered species, harbors several parasites. Among the ectoparasites that it harbors, ear mites of the genus Loxanoetus have the potential to cause external otitis, an inflammation that may also be associated with the presence of other microorganisms. We assessed the relationships between ear mites, nematodes, yeast, bacterial rods, and cocci sampled from the ears of captive Asian elephants in Thailand. In addition, we discuss the possibility that dust-bathing behavior may be triggered by ear mite infestation, and that this in turn may lead to contamination of the ears with soil microorganisms. Methods Legally owned captive Asian elephants (n = 64) were sampled. Ear swabs were individually collected from both ears and microscopically examined for the presence of mites, nematodes, yeast, bacterial rods, cocci, and host cells. Mites and nematodes were identified to species level using morphological and molecular methods. Results Loxanoetus lenae mites were present in 43.8% (n = 28/64) of the animals (19 animals with mites in one ear and nine animals with mites in both ears). Nematodes of the genus Panagrolaimus were detected in 23.4% (n = 15/64) of the animals (10 with nematodes in one ear and five with nematodes in both ears). In adult elephants (Fisher’s exact test, P = 0.0278) and female elephants (Fisher’s exact test, P = 0.0107), the presence of nematodes in both ears was significantly associated with the presence of mites. In addition, higher categorical burdens of nematodes were also significantly associated with the presence of mites (Fisher’s exact test, P = 0.0234) and epithelial cells (Fisher’s exact test, P = 0.0108), and marginally significantly associated with bacterial cocci (Fisher’s exact test, P = 0.0499). Conclusions The presence of L. lenae mites in the ear canals of the Asian elephants was significantly associated with the occurrence of other microorganisms, such as soil nematodes, bacteria and yeasts. The presence of mites in their ears may increase the dust-bathing behavior of elephants which, if confirmed, represents a further paradigmatic example of a parasitic infestation affecting animal behavior. Graphical Abstract |
| first_indexed | 2024-04-09T23:08:09Z |
| format | Article |
| id | doaj.art-0fb8f10112044cfa85868d99c6cefcf7 |
| institution | Directory Open Access Journal |
| issn | 1756-3305 |
| language | English |
| last_indexed | 2024-04-09T23:08:09Z |
| publishDate | 2023-03-01 |
| publisher | BMC |
| record_format | Article |
| series | Parasites & Vectors |
| spelling | doaj.art-0fb8f10112044cfa85868d99c6cefcf72023-03-22T10:33:53ZengBMCParasites & Vectors1756-33052023-03-0116111210.1186/s13071-023-05708-1Into the large ears: otitis externa associated with nematodes, mites, and bacteria in Asian elephants (Elephas maximus)Marcos Antonio Bezerra-Santos0Jairo Alfonso Mendoza-Roldan1Peter M. DiGeronimo2Erica Ward3Bruce Noden4Francesca De Luca5Elena Fanelli6Domenico Valenzano7Riccardo Paolo Lia8Domenico Otranto9Department of Veterinary Medicine, University of BariDepartment of Veterinary Medicine, University of BariPhiladelphia ZooWildlife and Animal Welfare InstituteDepartment of Entomology and Plant Pathology, Oklahoma State UniversityInstitute for the Sustainable Protection of Plants, National Research CouncilInstitute for the Sustainable Protection of Plants, National Research CouncilDepartment of Soil, Plant and Food Sciences, University of BariDepartment of Veterinary Medicine, University of BariDepartment of Veterinary Medicine, University of BariAbstract Background The Asian elephant (Elephas maximus), which is an endangered species, harbors several parasites. Among the ectoparasites that it harbors, ear mites of the genus Loxanoetus have the potential to cause external otitis, an inflammation that may also be associated with the presence of other microorganisms. We assessed the relationships between ear mites, nematodes, yeast, bacterial rods, and cocci sampled from the ears of captive Asian elephants in Thailand. In addition, we discuss the possibility that dust-bathing behavior may be triggered by ear mite infestation, and that this in turn may lead to contamination of the ears with soil microorganisms. Methods Legally owned captive Asian elephants (n = 64) were sampled. Ear swabs were individually collected from both ears and microscopically examined for the presence of mites, nematodes, yeast, bacterial rods, cocci, and host cells. Mites and nematodes were identified to species level using morphological and molecular methods. Results Loxanoetus lenae mites were present in 43.8% (n = 28/64) of the animals (19 animals with mites in one ear and nine animals with mites in both ears). Nematodes of the genus Panagrolaimus were detected in 23.4% (n = 15/64) of the animals (10 with nematodes in one ear and five with nematodes in both ears). In adult elephants (Fisher’s exact test, P = 0.0278) and female elephants (Fisher’s exact test, P = 0.0107), the presence of nematodes in both ears was significantly associated with the presence of mites. In addition, higher categorical burdens of nematodes were also significantly associated with the presence of mites (Fisher’s exact test, P = 0.0234) and epithelial cells (Fisher’s exact test, P = 0.0108), and marginally significantly associated with bacterial cocci (Fisher’s exact test, P = 0.0499). Conclusions The presence of L. lenae mites in the ear canals of the Asian elephants was significantly associated with the occurrence of other microorganisms, such as soil nematodes, bacteria and yeasts. The presence of mites in their ears may increase the dust-bathing behavior of elephants which, if confirmed, represents a further paradigmatic example of a parasitic infestation affecting animal behavior. Graphical Abstracthttps://doi.org/10.1186/s13071-023-05708-1ElephantsMitesNematodesExternal otitisBacteriaYeasts |
| spellingShingle | Marcos Antonio Bezerra-Santos Jairo Alfonso Mendoza-Roldan Peter M. DiGeronimo Erica Ward Bruce Noden Francesca De Luca Elena Fanelli Domenico Valenzano Riccardo Paolo Lia Domenico Otranto Into the large ears: otitis externa associated with nematodes, mites, and bacteria in Asian elephants (Elephas maximus) Parasites & Vectors Elephants Mites Nematodes External otitis Bacteria Yeasts |
| title | Into the large ears: otitis externa associated with nematodes, mites, and bacteria in Asian elephants (Elephas maximus) |
| title_full | Into the large ears: otitis externa associated with nematodes, mites, and bacteria in Asian elephants (Elephas maximus) |
| title_fullStr | Into the large ears: otitis externa associated with nematodes, mites, and bacteria in Asian elephants (Elephas maximus) |
| title_full_unstemmed | Into the large ears: otitis externa associated with nematodes, mites, and bacteria in Asian elephants (Elephas maximus) |
| title_short | Into the large ears: otitis externa associated with nematodes, mites, and bacteria in Asian elephants (Elephas maximus) |
| title_sort | into the large ears otitis externa associated with nematodes mites and bacteria in asian elephants elephas maximus |
| topic | Elephants Mites Nematodes External otitis Bacteria Yeasts |
| url | https://doi.org/10.1186/s13071-023-05708-1 |
| work_keys_str_mv | AT marcosantoniobezerrasantos intothelargeearsotitisexternaassociatedwithnematodesmitesandbacteriainasianelephantselephasmaximus AT jairoalfonsomendozaroldan intothelargeearsotitisexternaassociatedwithnematodesmitesandbacteriainasianelephantselephasmaximus AT petermdigeronimo intothelargeearsotitisexternaassociatedwithnematodesmitesandbacteriainasianelephantselephasmaximus AT ericaward intothelargeearsotitisexternaassociatedwithnematodesmitesandbacteriainasianelephantselephasmaximus AT brucenoden intothelargeearsotitisexternaassociatedwithnematodesmitesandbacteriainasianelephantselephasmaximus AT francescadeluca intothelargeearsotitisexternaassociatedwithnematodesmitesandbacteriainasianelephantselephasmaximus AT elenafanelli intothelargeearsotitisexternaassociatedwithnematodesmitesandbacteriainasianelephantselephasmaximus AT domenicovalenzano intothelargeearsotitisexternaassociatedwithnematodesmitesandbacteriainasianelephantselephasmaximus AT riccardopaololia intothelargeearsotitisexternaassociatedwithnematodesmitesandbacteriainasianelephantselephasmaximus AT domenicootranto intothelargeearsotitisexternaassociatedwithnematodesmitesandbacteriainasianelephantselephasmaximus |