Blood volume in hooded seals: implications for diving capacity

• Published in: Canadian Journal of Zoology
• Main Author: Cabanac, A J
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 2000
• Subjects: Animal Science and Zoology; Ecology, Evolution, Behavior and Systematics; Cystophora cristata; Greenland; Sea ice
• Online Access: http://dx.doi.org/10.1139/z00-077; http://www.nrcresearchpress.com/doi/pdf/10.1139/z00-077

Plasma volumes of seven adult hooded seals, Cystophora cristata (two males and five females; body mass (M) range = 110-234 kg), captured on sea ice off east of Greenland during breeding (March-April), ranged between 35 and 54 mL/kg M (median = 46.5 mL/kg M). Linear regression analysis of haemoglobin (Hb) concentrations (g/dL) and hematocrit (Hct; %) levels in venous blood yielded: Hb = 0.296Hct + 5.53 (r 2 = 0.96, n = 7). Aortic Hct of 11 adult and juvenile seals with contracted and dilated spleens ranged between 62 and 67% (median = 66.5%, n = 5) and 50 and 67.5% (58.5%, n = 6), respectively, with the differences between groups being significant (p < 0.05). The calculated blood volume range was 104-162 mL/kg M (median = 139 mL/kg M, n = 7). The skeletal muscle mass of two adult females represented 30.8 and 28.1% of their M. Based on this, the body oxygen store of a 150-kg seal was estimated to be 9.8 L O 2 , of which only about 0.9 L O 2 (9%) could be stored in the fully dilated spleen. In assuming a diving aerobic metabolic rate of 1-2 times the predicted basal metabolic rate, the calculated aerobic dive limit was estimated to be 11.3-22.6 min.