Trace Element Levels in the Serum of Hermann´s Tortoises (Testudo hermanni)

Abstract

Up to now, blood reference values for trace elements (zinc, copper, iodine, iron, selenium and manganese) in the serum of Testudo spp. have not been established. Most studies concerning trace element levels in blood of reptile’s regard environmental pollution esp. concerning selenium. In the present study levels of iron, copper, iodine, zinc, selenium and manganese were evaluated in 130 blood samples of clinically healthy Hermann´s Tortoises (Testudo hermanni), originating from pet tortoises in Germany (n= 64), extensively kept captive-hatched tortoises from Turkey (n=20), and from free-ranging specimens of two locations in France (n=46). The French habitats differ in the nature of the soils, one being low in lime and another high in lime. The levels of trace elements in the blood were compared between the different groups and to the levels of trace elements in the respective feed rations resp. food plants. The aim was to check the correlation between origin, husbandry, feeding and sex on the levels of trace elements in the blood. Blood levels of trace elements, regardless of origin, gender, or diet, generally showed a wide range. Also there existed a poor correlation to contents in diet concerning iron, selenium, and manganese, but a statistically significant correlation to zinc, copper and iodine. Preliminary reference values of zinc, iodine and copper can be a useful tool to diagnose nutrient deficiencies, poisoning and deficiency symptoms in Testudo hermanni.