Hematological and Plasma Biochemical Trends by Trimester in Healthy Pregnant Bottlenose Dolphins (Tursiops truncatus)
Abstract
In terrestrial animals and humans, maternal expansion of plasma volume and resource demands of the fetus can produce species-specific and trimester-specific alterations in hematological and biochemical analytes.1-5 To more effectively interpret blood results throughout pregnancy, a retrospective analysis of 15 bottlenose dolphins (33 successful pregnancies, 347 blood samples) was conducted to compare blood values among trimesters. During the third trimester compared to the first and second trimesters, MCH, protein, albumin, and GFR were higher and MCHC, platelets, lymphocytes, creatinine, inorganic phosphate, and alkaline phosphatase were lower. Liver transaminase (AST, ALT, LDH and GGT) and iron levels decreased during pregnancy, with significantly lower values during the third trimester. Neutrophils and segmented neutrophils were higher in the third trimester compared to the second trimester, but the total white blood cell count was not significantly different. Although the red blood cell count was lower in the second trimester compared to the first trimester, there was no significant difference in hematocrit between trimesters. The most pronounced changes in pregnant dolphin blood values occurred during the third trimester, which is similar to the results seen in killer whale pregnancies.4 These results indicate that similar hemodynamic shifts occur in bottlenose dolphin pregnancies as seen in other mammalian species. The most clinically relevant finding from this study is that indications of an inflammatory hemogram (increased segmented neutrophil count, decreased alkaline phosphatase and decreased iron) in the third trimester may be a normal expectation and not manifestation of a disease process.
Acknowledgments
The authors thank Kevin Carlin for his support with data management and statistical analyses. We also thank the numerous veterinarians, technicians, and trainers involved with the acquisition of these data at the U.S. Navy Marine Mammal Program and National Marine Mammal Foundation.
* Presenting author
+ Student presenter
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