🇺🇸 영어 원문
Pygmy sperm whales (Kogia breviceps) are some of the least understood mammals in the ocean. They spend most of their lives far from shore, usually traveling in small groups and diving deep to hunt squid and fish. Because they are quiet, secretive, and rarely seen at the surface, scientists have had few opportunities to observe them in the wild.
Much of what researchers know about pygmy sperm whales has come from animals that wash ashore. Strandings are especially common along the southeastern United States, where this species appears more frequently than almost any other large marine mammal.
Examinations of stranded whales have uncovered several recurring medical problems, including stomach ulcers. These ulcers are sometimes associated with Helicobacter, a group of bacteria that can live in the stomach and intestines of many animals, including humans and whales.
After reviewing more than 20 years of stranding records and preserved tissue samples, researchers at Florida Atlantic University’s Harbor Branch Oceanographic Institute and collaborating institutions identified three Helicobacter genotypes that had never been documented before.
The study, published in the Journal of Wildlife Diseases, marks the first confirmed discovery of these bacterial genotypes in pygmy sperm whales. The researchers named them Kogia Helicobacter 1, 2 and 3. Beyond offering new insight into an elusive whale species, the findings raise broader questions about how bacterial infections may affect marine wildlife and ocean health.
“Helicobacter bacteria have long been associated with gastrointestinal disorders in humans and other animals, including chronic gastritis, ulcers, and even gastric cancer,” said Annie Page, D.V.M., Ph.D., senior author, an associate research professor and clinical veterinarian at FAU Harbor Branch. “To find novel strains of these bacteria in a deep-diving whale species is intriguing.”
From 1999 through 2020, FAU Harbor Branch responded to 59 pygmy sperm whale strandings. Post-mortem examinations were completed on 80% of those animals.
In four cases, scientists found spiral-shaped, “spirilliform” bacteria within stomach tissue. The team later reexamined the preserved samples using histopathology, molecular testing and DNA sequencing. That analysis revealed several previously unknown Helicobacter genotypes.
“Two of the genotypes, Kogia Helicobacter 1 and 2, are genetically similar to known Helicobacter species previously found in other cetaceans — such as dolphins and porpoises — and in humans,” said Wendy Marks, corresponding author and a research coordinator of the marine wildlife veterinary medicine and research lab at FAU Harbor Branch. “But Kogia Helicobacter 3 belongs to a more divergent lineage, which emphasizes the possibility that there are far more undiscovered bacteria in the ocean than we realize.”
Researchers found both Kogia Helicobacter 1 and 3 in the forestomach tissue of one whale.
Each of the four whales that tested positive also showed clear signs of gastrointestinal disease.
“All four whales that tested positive for Helicobacter had visible gastric pathology,” said Page. “We saw signs of gastritis, gastric ulcers, fibrosis and nematode infestations. In one case, there was also colitis, which suggests that the infection may not be limited to the stomach. While Helicobacter wasn’t listed as the cause of death in any of the whales, these lesions indicate significant health impacts.”
🇰🇷 한국어 요약
작은 돌고래와 비슷한 크기인 왜소 수염고래는 바다에서 가장 이해하기 어려운 포유류 중 하나입니다. 이 고래들은 주로 깊은 바다에 살며 표면으로 잘 나오지 않아 관찰하기 어렵습니다. 과학자들은 주로 해변에 떠밀려 온 고래들을 연구해 왔는데, Florida Atlantic University 연구팀은 20 년 이상의 기록을 분석한 결과, 이 고래들의 위장에서 새로운 종류의 헬리코박터균을 발견했습니다. 특히 Kogia Helicobacter 3 은 다른 종과 유전적으로 많이 달라, 해양 생물과 인간의 건강에 대한 새로운 질문을 제기하고 있습니다.
🔑 핵심 단어 (Vocabulary)
- Elusive – 회피하기 쉬운, 찾기 어려운 – Scientists have had few opportunities to observe them because they are elusive.
- Stranding – (고래 등의) 좌초 – Strandings are especially common along the southeastern United States.
- Helicobacter – 헬리코박터 (세균의 일종) – These ulcers are sometimes associated with Helicobacter.
- Genotypes – 유전자형 – Researchers identified three Helicobacter genotypes that had never been documented before.
- Gastrointestinal – 위장관의 – Helicobacter bacteria have long been associated with gastrointestinal disorders.
- Pathology – 병리학, 병변 – All four whales that tested positive had visible gastric pathology.
- Histopathology – 조직병리학 – The team reexamined samples using histopathology and DNA sequencing.
- Lineage – 계통, 가계 – Kogia Helicobacter 3 belongs to a more divergent lineage.
- Cetaceans – 고래목 동물 – Helicobacter species previously found in other cetaceans.
- Novel – 새로운, 낯선 – To find novel strains of these bacteria in a deep-diving whale species is intriguing.
🔗 원문 링크
https://www.sciencedaily.com/releases/2026/07/260721000847.htm