COMPARISON OF SUBCARAPACIAL SINUS AND BRACHIAL VEIN PHLEBOTOMY SITES FOR BLOOD COLLECTION IN FREE-RANGING GOPHER TORTOISES (GOPHERUS POLYPHEMUS).

Abstract

Paired blood samples were collected from the brachial vein and subcarapacial sinus of 42 wild gopher tortoises (Gopherus polyphemus) for comparison of hematological and plasma biochemical, vitamin, mineral, and protein electrophoresis parameters with general linear models with repeated measures designs. Comparisons revealed higher brachial vein mean values for 38 of 42 parameters with significance (P ≤ 0.05) for 21 parameters. Significantly lower brachial vein means were noted for two parameters. Coefficients of variation for brachial vein samples were lower for 30 out of 42 parameters with significantly lower values for 11 parameters. Of the 12 parameters with lower coefficients of variation for subcarapacial sinus samples, significant differences were noted for four parameters. Both the lower coefficient of variation and the higher mean values for most parameters from brachial vein samples are attributed to greater hemodilution of subcarpacial samples with lymph compared to the paired brachial vein samples. To address the clinical relevance and reliability of the parameter ranges obtained from both paired phlebotomy sites, we compared these values to those obtained from other selected investigations of gopher tortoise and desert tortoise (Gopherus agassizii) clinicopathology. Although statistically significant differences were detected, available data demonstrated that most mean ± standard deviation values and/or ranges for both phlebotomy sites of our study are similar to those reported for the selected studies. Based on these results, utilization of either set of our study values in the assessment of a gopher tortoise population or individual gopher tortoises would be acceptable for clinical or management decisions. It is also advisable that investigators develop institutional blood parameter ranges for healthy individuals by phlebotomy site when possible in addition to maintaining standardized sample collection and handling protocols.