Investigating Cardiovascular Disease and Associated Health Parameters and Pathologies of Bile-farmed Asiatic Black Bears (Ursus thibetanus)

• Main Author: Bando, Monica Kaho Herkules
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01-01-2019
• Subjects: Animal sciences; Aspiration; Disease; Disorders; Medicine; Veterinary medicine; Veterinary services; Wildlife Conservation
• ISBN: 9781687973061; 1687973067

Approximately 17,000 bears are farmed for bile across Asia for traditional medicine. Bears on farms are confined to small cages to facilitate bile extraction via needle aspiration or through surgically implanted catheters or transabdominal fistulas. Bears rescued from farms exhibit severe health problems including extreme abnormal behaviors, emaciation, abdominal infections, abscesses, and cholecystitis. Between 2009 and 2014, six rescued bears died from ruptured and/or dissecting aortic aneurysms, conditions not previously reported in bears. We identified a high prevalence of aortic dilation (>50%) in bile-extracted Asiatic black bears consistent with systemic hypertension. A high prevalence of other validated lesions of systemic hypertension were subsequently identified in this group of bears, such as left ventricular hypertrophy (74%) and retinal pathology (54%). Systemic hypertension often develops secondary to renal disease in other species. The objectives of this study were to test our hypothesis that a high incidence of renal disease is present in bile-extracted bears and is positively correlated with lesions of systemic hypertension. Medical records and archived laboratory samples from over 300 rescued bears were analyzed. Bile-extracted bears exhibited the highest values in laboratory parameters compared to all non-extracted bears particularly for liver and renal enzymes. Bile extracted bears arriving from farms with azotemia had a median survival time of 1 year, and biochemical derangements persisted in surviving bears up to 14 years, suggestive of chronic renal disease. Bears with lesions of systemic hypertension had a higher renal histopathology score than bears without these lesions. Glomerular pathology, interstitial fibrosis, and hydronephrosis were common renal pathologies. Lesions of systemic hypertension were positively correlated to parameters of renal disease, particularly renal histopathology score and serum creatinine, but not symmetric dimethylarginine (SDMA). Due to the significant comorbidities caused by chronic systemic hypertension, including aortic aneurysm rupture, there is a critical need to elucidate the relationship between renal disease and lesions of systemic hypertension in bile-extracted bears as increasing numbers of bears are being rescued form bile farms with these conditions. Findings from this study will also raise awareness about the health and welfare consequences of bile farming and potentially impact bile-farming policy.