Project description:Cardiomyopathy is a heart muscle disease and diagnosis relies on radiography and echocardiography, while blood-based markers are lacking. Development of a non-invasive test would be useful when imaging is not possible (e.g., prenatal diagnosis). In southern sea otters (Enhydra lutris nereis), cardiomyopathy is a prevalent cause of mortality and antemortem diagnosis is challenging. Sea otters requiring clinical care are at significant anesthetic risk if cardiomyopathy is present. A blood-based assay would improve triage decisions, case management, and treatment protocols to safeguard against co-morbidities. With support from the Oiled Wildlife Care Network, we analyzed undepleted sea otter serum using mass spectrometry-based proteomics. Though the larger sample set included 63 sera (that included a validation set of 22 sera with class labels blinded to the data collector), we a priori compared only samples from wild otters. Additionally, we generated proteomic data for four heat tissues with paired sera. These results demonstrate the utility of proteomic analysis, offer a glimpse into the sea otter proteome, and serve as a reference data set for relative protein abundance in sera and cardiac tissue.
Project description:Ancient mitogenomes from Oregon sea otters (Enhydra lutris): genetic and archaeological contributions to the historical ecology of an extirpated population.
Project description:Parasitism, particularly in concert with other sublethal stressors, may play an important, yet underappreciated role in morbidity and mortality of threatened species. During necropsy of southern sea otters (Enhydra lutra nereis) from California submitted to the Marine Wildlife Veterinary Care and Research Center's Sea Otter Necropsy Program between 1999 and 2017, pathologists occasionally observed nasopulmonary mites infesting the respiratory tracts. Infestation was sometimes accompanied by lesions reflective of mite-associated host tissue damage and respiratory illness. Our objectives were to estimate prevalence of nasopulmonary mites, determine the taxonomic identity of the observed mites, and create a DNA reference for these organisms in southern sea otters as an aid in population management. Using unique morphological characteristics discerned via light and scanning electron microscopy (SEM), we identified the mites as Halarachne halichoeri, a species typically associated with harbor seals (Phoca vitiluna). The 18S, 16S, 28S and ITS1-2 genetic regions were sequenced and submitted to GenBank. We observed H. halichoeri mites in 25.6% (95% CI 19.9-33.4%). of southern sea otters from a subset of necropsies performed between 2012 and 2017. This is the first documentation of H. halichoeri in southern sea otters and is suggestive of parasite exchange between sea otters and harbor seals.