Cutaneous nodules in Irrawaddy dolphins: an emerging disease in vulnerable populations

The presence of cutaneous nodules is reported in vulnerable populations of Irrawaddy dolphins Orcaella brevirostris from Malaysia (Kuching, Bintulu-Similajau, Kinabatangan-Segama and Penang Island), India (Chilika Lagoon) and Bangladesh (Sundarbans). Approximately 5700 images taken for photo-identif...

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Main Authors: Van Bressem, Marie-Francoise, Minton, Gianna, Sutaria, Dipani, Kelkar, Nachiket, Peter, Cindy, Mohammad, Zulkarnaen, Rubaiyat, M. Mansur, Porter, Lindsay, Rodriguez Vargas, Luz H., Rajamani, Leela
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Published: Inter-Research 2014
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Online Access:http://ir.unimas.my/id/eprint/6589/
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author Van Bressem, Marie-Francoise
Minton, Gianna
Sutaria, Dipani
Kelkar, Nachiket
Peter, Cindy
Mohammad, Zulkarnaen
Rubaiyat, M. Mansur
Porter, Lindsay
Rodriguez Vargas, Luz H.
Rajamani, Leela
author_facet Van Bressem, Marie-Francoise
Minton, Gianna
Sutaria, Dipani
Kelkar, Nachiket
Peter, Cindy
Mohammad, Zulkarnaen
Rubaiyat, M. Mansur
Porter, Lindsay
Rodriguez Vargas, Luz H.
Rajamani, Leela
author_sort Van Bressem, Marie-Francoise
building UNIMAS Institutional Repository
collection Online Access
description The presence of cutaneous nodules is reported in vulnerable populations of Irrawaddy dolphins Orcaella brevirostris from Malaysia (Kuching, Bintulu-Similajau, Kinabatangan-Segama and Penang Island), India (Chilika Lagoon) and Bangladesh (Sundarbans). Approximately 5700 images taken for photo-identification studies in 2004 to 2013 were examined for skin disorders. Nodules were detected in 6 populations. They appeared as circumscribed elevations of the skin and varied in size from 2 to >30 mm, were sparse or numerous and occurred on all visible body areas. In 8 photo-identified (PI) dolphins from India and Malaysia, the lesions remained stable (N = 2) or progressed (N = 6) over months but did not regress. The 2 most severely affected individuals were seen in Kuching and the Chilika Lagoon. Their fate is unknown. Cutaneous nodules were sampled in a female that died in a gillnet in Kuching in 2012. Histologically, the lesions consisted of thick collagen bundles covered by a moderately hyperplasic epithelium and were diagnosed as fibropapillomas. Whether the nodules observed in the other O. brevirostris were also fibropapillomas remains to be investigated. Disease prevalence ranged from 2.2% (N = 46; Bintulu-Similajau) to 13.9% (N = 72; Chilika) in 4 populations from Malaysia and India. It was not significantly different in 3 study areas in eastern Malaysia. In Chilika, prevalence was significantly higher (p = 0.00078) in 2009 to 2011 (13.9%) than in 2004 to 2006 (2.8%) in 72 PI dolphins. The emergence of a novel disease in vulnerable O. brevirostris populations is of concern.
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institution Universiti Malaysia Sarawak
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spelling unimas-65892015-03-19T02:47:46Z http://ir.unimas.my/id/eprint/6589/ Cutaneous nodules in Irrawaddy dolphins: an emerging disease in vulnerable populations Van Bressem, Marie-Francoise Minton, Gianna Sutaria, Dipani Kelkar, Nachiket Peter, Cindy Mohammad, Zulkarnaen Rubaiyat, M. Mansur Porter, Lindsay Rodriguez Vargas, Luz H. Rajamani, Leela QH301 Biology QL Zoology The presence of cutaneous nodules is reported in vulnerable populations of Irrawaddy dolphins Orcaella brevirostris from Malaysia (Kuching, Bintulu-Similajau, Kinabatangan-Segama and Penang Island), India (Chilika Lagoon) and Bangladesh (Sundarbans). Approximately 5700 images taken for photo-identification studies in 2004 to 2013 were examined for skin disorders. Nodules were detected in 6 populations. They appeared as circumscribed elevations of the skin and varied in size from 2 to >30 mm, were sparse or numerous and occurred on all visible body areas. In 8 photo-identified (PI) dolphins from India and Malaysia, the lesions remained stable (N = 2) or progressed (N = 6) over months but did not regress. The 2 most severely affected individuals were seen in Kuching and the Chilika Lagoon. Their fate is unknown. Cutaneous nodules were sampled in a female that died in a gillnet in Kuching in 2012. Histologically, the lesions consisted of thick collagen bundles covered by a moderately hyperplasic epithelium and were diagnosed as fibropapillomas. Whether the nodules observed in the other O. brevirostris were also fibropapillomas remains to be investigated. Disease prevalence ranged from 2.2% (N = 46; Bintulu-Similajau) to 13.9% (N = 72; Chilika) in 4 populations from Malaysia and India. It was not significantly different in 3 study areas in eastern Malaysia. In Chilika, prevalence was significantly higher (p = 0.00078) in 2009 to 2011 (13.9%) than in 2004 to 2006 (2.8%) in 72 PI dolphins. The emergence of a novel disease in vulnerable O. brevirostris populations is of concern. Inter-Research 2014 Article PeerReviewed Van Bressem, Marie-Francoise and Minton, Gianna and Sutaria, Dipani and Kelkar, Nachiket and Peter, Cindy and Mohammad, Zulkarnaen and Rubaiyat, M. Mansur and Porter, Lindsay and Rodriguez Vargas, Luz H. and Rajamani, Leela (2014) Cutaneous nodules in Irrawaddy dolphins: an emerging disease in vulnerable populations. Diseases Of Aquatic Organisms, 107 (3). pp. 181-189. doi: 10.3354/dao02689
spellingShingle QH301 Biology
QL Zoology
Van Bressem, Marie-Francoise
Minton, Gianna
Sutaria, Dipani
Kelkar, Nachiket
Peter, Cindy
Mohammad, Zulkarnaen
Rubaiyat, M. Mansur
Porter, Lindsay
Rodriguez Vargas, Luz H.
Rajamani, Leela
Cutaneous nodules in Irrawaddy dolphins: an emerging disease in vulnerable populations
title Cutaneous nodules in Irrawaddy dolphins: an emerging disease in vulnerable populations
title_full Cutaneous nodules in Irrawaddy dolphins: an emerging disease in vulnerable populations
title_fullStr Cutaneous nodules in Irrawaddy dolphins: an emerging disease in vulnerable populations
title_full_unstemmed Cutaneous nodules in Irrawaddy dolphins: an emerging disease in vulnerable populations
title_short Cutaneous nodules in Irrawaddy dolphins: an emerging disease in vulnerable populations
title_sort cutaneous nodules in irrawaddy dolphins: an emerging disease in vulnerable populations
topic QH301 Biology
QL Zoology
url http://ir.unimas.my/id/eprint/6589/
http://ir.unimas.my/id/eprint/6589/