Department of Physiology and Biophysics, University of Southern California, School of Medicine.
UNDERSTANDING AND INTERPRETING HEMATOCRIT MEASUREMENTS IN PINNIPEDS
Article first published online: 26 AUG 2006
Marine Mammal Science
Volume 12, Issue 2, pages 251–264, April 1996
How to Cite
Castellini, J. M., Meiselman, H. J. and Castellini, M. A. (1996), UNDERSTANDING AND INTERPRETING HEMATOCRIT MEASUREMENTS IN PINNIPEDS. Marine Mammal Science, 12: 251–264. doi: 10.1111/j.1748-7692.1996.tb00574.x
- Issue published online: 26 AUG 2006
- Article first published online: 26 AUG 2006
- Received: 15 March 1995 Accepted: 26 June 1995
- Coulter counter;
- cell volume
Hematocrit data are relatively easily obtained from blood samples of pinnipeds but differences in methodology and variable physiological conditions of the subjects can significantly alter their values. This two-fold problem makes comparative data and modeling efforts difficult. To quantify the difficulty of obtaining accurate and representative hematocrit values in pinnipeds, hematocrit was measured by both microcentrifugation and Coulter counter methods in a range of pinnipeds under a variety of physiological and handling conditions. The data show that the Coulter counter hematocrit values were 4%-15% higher than those measured by microcentrifugation. In addition, blood samples from restrained animals showed consistently elevated hematocrit values relative to resting subjects. A significant difference was also found between hematocrit values from pups and adults. Finally, hematocrit was shown to decline over the course of isofluorane anesthesia. Taken together, these results suggest that laboratory methodology, developmental state, and animal handling techniques can significantly alter hematocrit values in pinnipeds. Thus, modeling efforts that require representative hematocrit values, such as calculations of total blood oxygen stores, can be markedly impacted by variations in hematocrit measurement techniques and sampling regimes.