I used blood chemistry and hematology to evaluate the physical condition of black bears (Ursus americanus). Analyses were performed on 70 blood samples taken from 55 live-captured black bears in the redwood (Sequoia sempervirens) region in northcoastal California. Blood parameters analyzed included calcium, inorganic phosphorus, total protein, albumin, creatinine, blood urea nitrogen (BUN), glucose, cholesterol, triglycerides, uric acid, total bilirubin, direct bilirubin, alkaline phosphatase, GGT, SGOT, SGPT, LDH, sodium, potassium, chloride, ferrous, total globulins, WBC, RBC, HGB, HCT, MVC, MCH, and MCHC. Bears captured in Aldrich foot-snares, chased up trees with trained dogs, or immobilized with sedative darts while free-roaming had significantly greater (P < 0.01) WBC and serum levels of uric acid, SGOT, SGPT, and LDH, and lower levels of inorganic phosphorus than bears captured in culvert traps. Male bears had significantly (P < 0.01) less MCH than female bears. Additional significantly different (P < 0.05) blood values between sexes suggest a differential stress response of females to immobilization and handling procedures. Adult bears had significantly (P < 0.01) higher MCV, MCH, and serum levels of triglycerides and lower levels of alkaline phosphatase than subadults or cubs. Seasonal differences were observed for inorganic phosphorus, total protein, creatinine, total globulins, MCH, and MCHC. These latter differences were probably a result of adult male capture bias in spring and subadult capture bias in fall. Six indices of physical condition were developed. Each bear was assigned a condition evaluation index (CEI) value based on subjective assessment of body fat deposits, number and types of parasites, and pelage condition. Five physical condition ratio (PCR) values were calculated by dividing body weight by each of 5 somatic measurements (total length, girth, height at shoulder, head circumference, and head length). The CEI did not reflect physical condition as well as the PCR values. The ratio body weight/total length (PCR-A) permitted objective physical condition comparisons between sex and age classes. These comparisons suggest relationships between and within sex and age classes based on intraspecific competition for available resources. Blood parameters significantly correlated (P < 0.005) with PCR-A (total protein, albumin, total globulins, triglyceride, glucose, RBC, HGB, HCT, MCH, and MCHC) may be used to monitor the nutritional status of black bear populations under a variety of conditions.
- Volume 7
- Issue
- Pages 333-349
- Publication Date 1 January 1987
- DOI 10.2307/3872641
- File Size 569.70 KB
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