Brucella ceti Surveillance in Stranded Hawaiian Cetaceans

• Main Author: Warner, Angela
• Other Authors: Odani, Jenee, Human Nutrition, Food and Animal Sciences
• Format: Text
• Language: unknown
• Published: University of Hawaii at Manoa 2020
• Subjects: Humpback Whale; Killer Whale; Megaptera novaeangliae; Sperm whale; Killer whale
• Online Access: https://hdl.handle.net/10125/104432

This project surveys nine stranded Hawaiian cetaceans for Brucella ceti, a bacterial pathogen recognized within the genus Brucella. Brucella spp. can cause brucellosis, which has emerged as a disease of concern in marine mammals in the last two decades. Despite host-based segregation, Brucella spp. have proven challenging to differentiate using molecular techniques. The techniques utilized in this project are both conventional and real-time PCR. The project aims to find successful primers and probes for PCR and determine which tissues would be most successful for targeted testing. Samples were chosen based on the animal’s history, condition, and tissue availability. The positive control used in this study is from the only confirmed cetacean with Brucella in Hawaii, Physeter macrocelphaus, the sperm whale, which stranded on Oahu in 2011. The following species are examined: Lagenodelphis hoseii, Fraser’s Dolphin; Peponocephala electra, Melon-headed Whale; Feresa attenuata, Pygmy Killer Whale; Megaptera novaeangliae, Humpback Whale fetus; and Stenella coeruleoalba, Striped Dolphin. The target tissues included the cerebrum, lung, spleen, marginal or mediastinal lymph nodes, and the liver. Samples were retrieved from the University of Hawaii Marine Mammal Stranding Program. The sperm whale samples that produced amplification of the DNA sequence were the spleen, and mediastinal and tracheobronchial lymph nodes. The unknown samples from the various species tested negative for Brucella spp. The real-time PCR did not detect amplification in any of the samples, including the positive controls; the primers were possibly not specific for the B. ceti strain studied.