NSB DWM

Marine mammal subsistence hunting has sustained the Tissues from subsistence harvested seals North Slope Iñupiat Eskimos for thousands of years. The and walruses were collected by CSU ringed seal (Phoca hispida), bearded seal (Erignathus veterinary student Greta M. Krafsur barbatus) and walrus (Odobenus rosmarus divergens) are during the summers of 2008 and 2009. very important subsistence resources. Diminishing sea ice, Routine formalin-fixed tissues were increased ship traffic and expanding oil and gas prepared and examined at the Colorado Greta M. Krafsur 1,2, Terry R. Spraker1, Billy Adams2, Craig C. George2, Cyd Hanns2, Robert Suydam2, Taqulik Hepa2 development in the Chukchi and Beaufort Seas have the State University Diagnostic Medicine ,Harry Brower, Jr.2. 1CSU Veterinary Diagnostic Medicine Center, Fort Collins, CO, 2North Slope Borough Department potential to devastate habitat critical to the survival of the of Wildlife Management, Barrow, AK. Center. These slides were read by Greta animals that feed and clothe subsistence hunters and their with the guidance of a marine mammal families. Scientists with the North Slope Borough pathologist, Terry R. Spraker, DACVP. Abstract Department of Wildlife Management in Barrow, Alaska are Routine histological examination of formalin-fixed tissues obtained from subsistence harvested seals and working closely with community members from the North walruses taken near the North Slope Borough villages of Barrow and Wainwright, Alaska was conducted in Photos below demonstrate mild exertional rhabdomyolysis, a Slope Borough villages to monitor the health of subsistence order to survey these important subsistence resources for evidence of contaminant exposure, disease common histological finding in sections of skeletal muscles resources with the intent of generating baseline datasets surveillance, and infection with zoonotic pathogens. Mild exertional rhabdomyolysis with loss of from ringed and bearded seals and walruses. Rhabdomyolysis from areas not yet impacted by industrial development. sarcoplasmic detail, fragmentation, myositis, repair and healing was consistently observed. Sarcocysts describes damage to skeletal muscle fibers that may provide a were identified in the skeletal muscles of seals, but not walruses. Endoarteritis in ringed seals with useful tool for documenting the negative impact of receding moderate to severe myointimal proliferation, fragmentation of the internal elastic membrane, and sea ice and ice platforms critical for mating, birthing and thrombi formation indicative of Acanthocheilonema spirocauda infection was repeatedly observed. resting. Parafilaroides spp were positively identified in sections of lungs from ringed seals and were implicated in the presence of verminous pneumonia in bearded seals. A consistent finding among all sections of liver examined from seals and walruses was focal areas of hypertrophied Kupffer cells, occasional neutrophils and lymphoplasmacytic infiltration suggestive of parasitic migration through the liver parenchyma. Positive identification of eggs and flukes consistent with Orthosplanchnus spp infection along with moderate to severe chronic active cholangitis, cholangiohepatitis and hepatocellular necrosis caused by fluke presence was a common finding. The same flukes were responsible for inflammation and fibrosis of the pancreatic ducts and periportal fibrosis. One seal had a focus of severe chronic granulomatous pancreatitis with focal peritonitis. There was no histopathological evidence of renal colonization with Hypercontracted Segment of Loss of Sarcoplasmic Detail, Mixed Mononuclear Healing and Repair with Removal Leptospira spp. Histological evidence of immunosuppression or endocrine disruption associated with Bearded Seal Myofiber-Note Myofiber Fragmentation, Inflammatory Infiltrate of Necrotic Myofibers environmental contaminant exposure was not observed. Rounded Appearance Cleavage

Small and large variant sarcocysts were repeatedly Parafilaroides spp in Bearded Seal Digestive Lung identified in bearded and ringed seal skeletal muscle Tract sections, but not walrus skeletal muscle. Protozoal Female infections of the skeletal muscles of domestic and wildlife Male Periductular Fibrosis, species is not an uncommon finding, these species are Female Verminous Chronic Intrahepatic Dilated Bile Duct, Biliary intermediate hosts for Sarcocystis spp, becoming infected Pneumonia Cholangitis Fluke Hyperplasia upon ingestion of sporulated oocysts. Sporozoites are released upon ingestion, migrating to muscle tissue where Occasional lungworms were identified in the alveolar spaces of they encyst, largely evading host defense mechanisms, ringed and bearded seals with rare verminous pneumonia. Limited inflammation is generally limited. IHC and PCR techniques host reaction suggests a parasite well adapted to the host lung are underway to determine if indeed this particular tissues. Additionally, the parasite is viviparous, failing to produce sarcocyst is different from others described in existing Hepatocellular Necrosis antigenic debris from embryonating eggs. Greater cause for marine mammal literature. 10X 20X 40X concern is the risk for Brucella transmission to seals infected with The principal investigator wishes to acknowledge the overwhelming kindness the lungworm- IHC staining for immunoreactivity to Brucella Gross and histological lesions pathognomonic for liver fluke disease in and generosity extended to her by members of the North Slope villages, antibodies is planned in those sections of lung tissues positive for bearded seals were repeatedly observed, ranging from mild neutrophilic allowing her to examine and collect tissues from their seals and walruses and Parafilaroides spp because the microorganism has been positively and lymphoplasmacytic infiltration consistent with immature fluke inviting her into their homes and lives to share in the fruits of their harvests. identified in the lungs of a harbor seal infected with the parasite. migrational tracts throughout the hepatic parenchyma to chronic active The contributions these people have made to the investigator’s veterinary cholangitis, cholestasis, cholangiohepatitis, and hepatocellular necrosis. pathology training and the marine mammal scientific community exemplify Adult flukes consistent with Orthosplanchnus spp were identified in the the potential for cooperation and collaboration between susbistence intrahepatic and extrahepatic bile ducts. Despite the untoward hunters, traditional knowledge and the scientific community. Quyanaqpak!

NSB DWM pathological sequelae associated with fluke infection, body condition of infected bearded seals remained excellent. Myointimal Proliferation Ringed Seal Lung, 10x 20x 40x Pulmonary lesions associated with the presence of heartworm, Acanthocheilonema spirocauda were routinely identified in sections from ringed seal lungs and included moderate to severe endoarteritis of Large Variant Sarcocyst Mature Sarcocyst medium-sized arteries with myointimal proliferation, fragmentation of Funding was provided by the the internal elastic membrane and thrombosis. The seal louse, William Inskeep Pathology Scholarship, Morris Animal Echinophthirius horridus serves as the intermediate host for the first Foundation, National Petroleum Reserve, Alaska State Department of three larval stages of the parasite. This sucking louse transmits the Echinophthirius Community and Economic infective L3 stage to the ringed seal with adult worms maturing in the horridus Development, North Slope Borough, right heart. In Kind Suppport from Terry R. Rare Eosinophilic Rare Myositis-Parasitic Spraker and the CSU Diagnostic Medicine Center Myositis-Parasitic Death Death