NONPIGMENTED VERSUS PIGMENTED: HEALTH VARIABLES AND GENETICS OF ALBINO FLORIDA GREEN TURTLE (CHELONIA MYDAS) HATCHLINGS COMPARED WITH NORMALLY PIGMENTED HATCHLINGS FROM THE SAME CLUTCH.

ABSTRACT

At the time of hatchling emergence from a nest laid on Juno Beach, Florida, US, by a normally pigmented green turtle (Chelonia mydas), 23 albino hatchlings and 75 normally pigmented hatchlings were observed. This condition is rarely seen in sea turtles, and little is known about blood analytes and genetics of albino wildlife to date. Therefore, the objective of our study was to assess and compare morphometric measurements (mass, minimum straight carapace length, body condition index), carapacial scute anomalies, a suite of hematologic and plasma biochemical analytes, and two glucose analysis methodologies (glucometer and dry chemistry analysis) in albino (n=20) versus normally pigmented (n=24) hatchlings from this nest. Genetic analyses were completed to identify paternal contributions of hatchlings and to test Mendelian inheritance assumptions. Although morphometric measurements, scute anomalies, and leukocyte morphology were similar between albino and normally pigmented hatchlings, several differences were observed in blood analyte data immature erythrocytes, packed cell volume, heterophillymphocyte ratio, and glucose concentrations (by both methodologies) were significantly higher, whereas absolute immature heterophils, absolute lymphocytes, number of erythrocyte micronuclei, sodium, and chloride were significantly lower in albino hatchlings compared with normally pigmented hatchlings. Considerations for these differences include a stress response from sampling (e.g., timing of procedures or possibly from photosensitivity or reduced visual acuity in albinos) and different osmoregulation, which may reflect physiologic variations or stress. There was a small positive bias (0.10 mmol/L) with glucose by glucometer, similar to reports in other sea turtle species and confirming its suitability for use in hatchlings. All albino hatchlings analyzed (n=10) were from the same father, but the normally pigmented hatchlings (n=24) were from two other fathers. These findings provide insight into the physiology and genetics of albinism in sea turtles.