Comparative leukocyte blood profile and size of blood cells of tortoises from the Samara Zoo

A comparative analysis of leukograms and morphometric features of blood cells of three species of tortoises from the Samara Zoo was carried out: Testudo horsfieldii Gray, 1844; Geochelone elegans (Schoepff, 1795); Chelonoidis carbonarius (Spix, 1824). Interspecies statistically significant differences in the total content of agranulocytes and granulocytes were revealed. The leukocyte profile indicated a pronounced innate immune response in tortoises and a more active cell-mediated adaptive response in C. carbonarius. According to the totality of integral indicators of the leukocyte profile, the most stable and balanced immune response was noted in T. horsfieldii. The variability of karyocytometric parameters of turtle blood cells was revealed. The share of variability in the area of cell nuclei, depending on the area of the cell itself, was the highest for different cells in different species: T. horsfieldii (basophils), G. elegans (platelets), C. carbonarius (eosinophils). The area of blood cells (with the exception of eosinophils) and the nuclear-cytoplasmic ratios of cells of the same type in different turtle species varied. A higher metabolic activity of blood cells of T. horsfieldii was established in comparison with G. elegans and C. carbonarius.