Effect of Age, Sex, Weight, and Rearing Condition on Blood Analytes in Juvenile Zebra Sharks (Stegostoma tigrinum)
Abstract
Despite zebra sharks’ (Stegostoma tigrinum) commonality within zoological institutions, conservation status,1 and subsequent captive breeding programs,2–4 information regarding bloodwork in juveniles is lacking. In addition, analytes may be affected by environmental factors5 or venipuncture site,6,7 complicating their clinical interpretation. The objective of this study was to determine the impact of age, sex, weight, and rearing condition on routinely examined blood analytes in juvenile zebra sharks. Weight and blood (caudal vein) were obtained from ten related sharks (4 females, 6 males) in two different systems once monthly for routine CBCs and plasma biochemistries. Mixed model regressions, with animal ID as level 2, were used to evaluate the effects of age, sex, weight, and system on 24 blood analytes. Significance was set at p=0.05. Sixteen (70%) analytes differed by age. Hematocrit, absolute lymphocytes, absolute monocytes, urea, triglycerides, total protein, globulins, calcium, phosphorus, sodium, chloride, and potassium all increased with age and absolute granulocytes, cholesterol, aspartate aminotransferase (AST), and lactate dehydrogenase (LD) decreased. Females had higher sodium and chloride compared to males. Twelve (52%) analytes were affected by weight. Absolute granulocytes, creatinine, cholesterol, AST, and LD increased with weight and absolute lymphocytes and monocytes, urea, calcium, sodium, chloride, and potassium decreased. Nine (39%) analytes were affected by system including hematocrit, absolute granulocytes, lymphocytes, monocytes, glucose, urea, triglycerides, calcium, and CO2. This dataset describes hematological values for juvenile zebra sharks and highlights the impact of age, sex, weight, and their environment over the course of early development.
Acknowledgements
The authors wish to thank the dedicated aquarists in the Aquarium Department and medical technologists in the veterinary services laboratory at SeaWorld Orlando for their time and significant efforts in helping to facilitate this project.
*Presenting author
+Student presenter
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