Translator Disclaimer
1 April 2017 Season, Sex and Age Variation in the Haematology and Body Condition of Geometric Tortoises Psammobates geometricus
Margaretha D Hofmeyr, Brian T Henen, Shasheen Walton
Author Affiliations +

Body condition and haematological indices provide powerful information when assessing wildlife health. Reference intervals for these indices can facilitate wildlife management, and would benefit initiatives to save the Critically Endangered geometric tortoise (Psammobates geometricus). We collected data from 126 geometric tortoises to establish baseline values reflecting variation over four seasons (spring 2000 to winter 2001) and among three groups (female, male and juvenile). We measured body condition index (BCI; mass to shell volume), blood urea nitrogen (BUN), plasma chloride, packed cell volume (PCV), haemoglobin concentration (Hb) and red blood cell count (RBC), and used PCV, Hb and RBC to calculate erythrocyte indices. BCI correlated poorly with haematological measures but had a strong inverse relationship with BUN. BCI did not vary among groups, but all groups had low condition indices in autumn, the end of the dry season. High BUN and chloride values in autumn indicate dehydration, particularly in males. Males had the highest PCV, Hb and RBC values, especially during summer and autumn when they moved long distances, likely pursuing mates. Female and juvenile indices were similar, except that female Hb was higher than juvenile Hb, possibly to meet female energy needs associated with their large size and reproductive metabolism. Low Hb levels in winter coincided with low temperatures and reduced movements. Our results illustrate how intrinsic and extrinsic factors influence the physiology of geometric tortoises and provide reference intervals to monitor their health.

© Zoological Society of Southern Africa
Margaretha D Hofmeyr, Brian T Henen, and Shasheen Walton "Season, Sex and Age Variation in the Haematology and Body Condition of Geometric Tortoises Psammobates geometricus," African Zoology 52(1), 21-30, (1 April 2017).
Received: 28 August 2016; Accepted: 1 January 2017; Published: 1 April 2017

blood urea nitrogen
erythrocyte indices
packed cell volume
red blood cell count
reference intervals
Get copyright permission
Back to Top