Case Study 1: What is killing CA sea otters?

What was found in the sea otters' autopsies?

Cysts in brain originally thought to be new pathogen

Generally, what was causing mass sea otter death?

Neurological disorder, getting disoriented, killed by sharks more

What molecular techniques were used to study?

PCR, genetic typing, etc.

What was the real pathogen?

Toxoplasma gondii - not new, been studied for a while

Toxoplasma Gondii

Protists found in land mammals, esp CATS, also rodents and birds

Main question about Toxoplasma Gondii

Pathogen of land mammals, how did it get into aquatic animal sea otters? born live die in water.

Route of transmission

Land mammals feces contain protists, dump into drains, got into water where animals never seen pathogen, no natural immunity, kills

Second issue

Need a lot of cysts ingested before does anything, how? Not water, but another component of diet

Diet of Sea Otters

Sea urchins, crabs, clams, mussels, octopus, fish, and other marine invertebrates >> filter feeders

Filter feeders

organism that takes in water to filter out the food and then releases the extra water (clam, oysters, sponge) >> filtering toxoplasma gondii cysts in water

Takeaways of Case Studies

Water quality is very important for all

Interdisciplinary Standpoint: Environment, Animal, and Human health are all connected

Changes made after this case study

Legislation prohibit dumping feces into drains