The foraging success, and thus the survival and reproductive success, of deep-diving pinnipeds such as the northern elephant seal, Mirounga angustirostris, depends on the ability to withstand repetitive breath-hold dives. Health parameters can be incorporated as potential explanatory variables for differences observed in diving and migratory performance of individual seals. Furthermore, biomedical samples from apparently healthy individuals can provide valuable baseline data for evaluating effects of natural or anthropogenic threats to individuals and populations. We evaluated 42 blood parameters in 134 northern elephant seals during the breeding and molting seasons (1992–1999) to test for age, sex, and seasonal differences and to develop reference ranges. Adult males sampled during the breeding season differed from all other adult groups for a suite of parameters often associated with inflammation, infection, or other stressors: lower hematocrit, higher white blood cell count, higher band neutrophils, higher neutrophil count, lower albumin, and lower serum iron. Adult females during the breeding season differed from all other adult categories for two parameters (lower platelet counts, lower alanine aminotransferase activity). Molting males had higher blood urea nitrogen than all other classes; creatinine did not differ between breeding and molting adult males, but was higher in males than in females in both seasons. We found significant differences among age classes for 24 of 42 parameters measured, including higher levels of triglycerides, total protein, calcium, and iron in pups than we found in juveniles or adults. Unlike other mammals which undergo substantial decreases in energy expenditure during prolonged fasting (e.g., hibernation), northern elephant seals defend territories, give birth and suckle large offspring, mate, and molt during their bi-annual fasts. Nonetheless, many studies have described physiologic homeostasis during fasting in elephant seals. The genus Mirounga is superbly adapted to going without feeding for extended periods, and this is reflected in our hematologic and serum biochemical profiles.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 44 • No. 4