Journal Article

Ingestion of fishing gear and Anisakis sp. infection in a beached Indo-Pacific finless porpoise (Neophocaena phocaenoides) in the Jeju Island, Republic of Korea: findings from post-mortem computed tomography and necropsy

Yuen, Adams Hei Long, Kim, Sang Wha, Kim, Sang Guen, Park, Se Chang, Giri, Sib Sankar, Baeck, Gun Wook, Hwang, Mae Hyun, Choe, Seongjun, Park, Dasol, Park, Eun Jae, Cho, Han Seok, Poon, Cherry Tsz Ching, Lee, Sung Bin, Kim, Sunmin, Jo, Su Jin, Kim, Byung Yeop, Park, Jae Hong, Lee, Young Min, Seo, Jong-pil, Kim, Do-Gyun, Jung, Won Joon

2024

Overview

Background Human fishing activities have significantly affect environmental concern for marine ecosystems, conservation of marine mammals, and human health. Coastal cetaceans are highly vulnerable to ingestion of fishing gear, bycatching, or entanglement, all of which can be fatal for these animals. In particular, certain coastal dolphins and porpoises are heavily impacted by fishing gear such as angling gear or stownet, as their food often overlap with the target fish species of human fisheries. Case presentation This study presents a case of an Indo-Pacific finless porpoise ( Neophocaena phocaenoides ) beached on the coast of Jeju Island, Republic of Korea, with ingestion of fishing gear and severe Anisakis infection. Although this species inhabits waters ranging from the Persian Gulf to Taiwan, several stranded carcasses have been reported on Jeju Island in recent years. Post-mortem computed tomography revealed a bundle of four fishing hooks in the forestomach, along with nylon lines and steel lines with connectors, which were assumed to be angling gear for Jeju hairtail ( Trichiurus lepturus ). Further necroscopic investigation revealed that the forestomach contained a large number of Anisakis spp. (Nematoda: Anisakidae). Histological examination revealed a thickened forestomach wall with pinpoint and volcanic ulcerations, a thickened layer of stratified squamous epithelium, and infiltrated stroma in the squamous epithelium. conclusions This study emphasizes the urgent need to address the impact of fishing activities on marine mammals, marine litter pollution, and the bycatch problem in Korean seawater. In addition, the occurrence of N. phocaenoides in seawater around Jeju Island should be raised in future geographical ecology or veterinary pathology studies and when its distribution is updated.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: animal pathology / Animals / Anisakiasis - parasitology / Anisakiasis - veterinary / Anisakis / Anisakis - isolation & purification / Autopsy / Bycatch / Case Report / Cetacea / Coasts / Computed tomography / Diagnostic imaging techniques / ecology / Ecosystems / Environmental aspects / Epithelium / fish / Fisheries / Fishing / Fishing equipment / Fishing hooks / Foreign bodies / Foreign body ingestion / forestomach / Health aspects / histology / human health / humans / Infections / ingestion / Liver / Lungs / Male / marine debris / Marine ecosystems / Marine litter / Marine mammals / Marine pollution / Medicine / Medicine & Public Health / Methods / Morphology / Necropsy / Neophocaena phocaenoides / nylon / Parasites / Persian Gulf / pollution / Porpoises / Porpoises - parasitology / Postmortem Imaging / Republic of Korea / seawater / South Korea / species / steel / Stranding / Stroma / Taiwan / Tomography / Tomography, X-Ray Computed - veterinary / Transgenics / Trichiurus lepturus / Ulceration / Veterinary Medicine/Veterinary Science / Veterinary public health and food security / Zoology