- Number 318 |
- August 16, 2010
Livermore Lab’s work with marine mammals gets ‘seal of approval’
Two harbor seals engage in
rest and relaxation. Scientists
from Lawrence Livermore
National Laboratory and the
Mammal Center are trying
to diagnose several diseases
that have struck the sea lions
and harbor seals.
Scientists from DOE's Lawrence Livermore National Laboratory and the Sausalito, Calif. -based Marine Mammal Center are working together to diagnose several diseases that have struck California sea lions and harbor seals.
In recent months, about 17 percent of the adult sea lions that have died at the Marine Mammal Center have succumbed to cancer, and others have become ill because of the bacterial disease leptospirosis, said Frances Gulland, the center’s director of veterinary science.
In June 2009, about 20 harbor seals died in Northern California from brain lesions, consisting of the premature death of living cells.
“The brain lesions are rare and unusual,” Gulland said. “We don’t understand why it happened. We are looking at two very different problems (in the brain lesions of the seals and the cancer of the sea lions).”
Gulland and her Livermore collaborator, biologist Crystal Jaing, are trying to determine whether there is a bacterial or viral basis for the brain lesions and cancer through the use of a new LLNL detection technology.
They are utilizing the Lawrence Livermore Microbial Detection Array (LLMDA), a device that can detect within 24 hours any virus or bacteria that has been sequenced and included among the array’s probes. The current operational version of the LLMDA contains 388,000 probes that can detect more than 2,000 viruses and about 900 bacteria.
Already, Livermore scientists have shown that their LLMDA device is excellent at detecting known viruses and bacteria, said team leader Tom Slezak, the head of the Lab’s Pathogen Bioinfomatics Group.
By working with the Marine Mammal Center to diagnose the causes of the sea lion and seal diseases, the team is attempting to determine how well they can perform pathogen discovery of as-yet-unsequenced viruses or bacteria, Slezak said.
To date, Livermore researchers have used the LLMDA to analyze frozen tissue samples from two deceased sea lions that were forwarded to them by the Marine Mammal Center.
One sample was found to have calicivirus, which would not have caused cancer, and the other sample had no virus or bacteria that could be positively identified and will now be sequenced by a company that assists LLNL, Jaing said.
Frozen tissue samples from eight other marine mammals, four from sea lions and four from harbor seals, will be analyzed in the coming months for bacterial or viral pathogens.
The cancer among sea lions is probably the most common cancer among wild animals in the United States, said Gulland, who expressed concern whether the cancer is caused by environmental exposures or infections.
In 2009, the Sausalito-based nonprofit center, which was established in 1975 as a hospital for sick marine mammals, treated about 1,700 such animals, including sea lions, harbor seals, elephant seals and dolphins.
The Marine Mammal Center’s mission is to expand knowledge about marine mammals, their health and the ocean environment. Its core work is the rescue and rehabilitation of sick and injured marine mammals.
Submitted by DOE's Lawrence Livermore National Laboratory