An investigation of factors influencing erythrocyte morphology of red-backed salamanders (Plethodon cinereus) (original) (raw)
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Integrative Zoology, 2013
Blood cell morphology and count are not uniform across species. Recently, between-species comparisons revealed that the size of red blood cells is associated with body size in some lizard taxa, and this finding was interpreted in the context of the metabolic theory. In the present study, we examined the numbers and the size of blood cells in 2 species of monitor lizards, the mangrove-dwelling monitor (Varanus indicus) and the savannah monitor (V. exanthematicus), and we compared these traits in individuals of different body size. The results revealed that during the course of ontogeny, the size of red blood cells increases with body mass. Because the mass-specific metabolic rate decreases with body size and the cell volume-to-surface ratio decreases with the cell size, changes in the erythrocyte size might be the result of oxygen transport adjustment. P. Frýdlová et al. P. Frýdlová et al.
Russian Journal of Theriology, 2020
The size of erythrocytes varies widely across mammals. Previously, deviations from allometric relationships and existence of factors regulating erythrocyte size other than body mass have been shown. The contribution of factors such as habitat and taxonomy are still under discussion. In the present study we examined the morphology of erythrocytes in rodent species and determined their diameter, and for Ondatra zibethicus and Sciurus vulgaris this was done for the first time. We discovered that erythrocyte diameter of the investigated rodent species ranged from 5.5 to 8.4 μm, varying by a factor of more than 1.5. We analyzed our own data obtained for 10 species as well as data from the literature for 22 species. We found that the size of erythrocytes depended on the phylogenetic position, environmental conditions and body mass.
Hematology of the Lycian Salamander, Lyciasalamandra fazilae
North-Western Journal of Zoology, 2009
Abstract. We examined some hematological parameters and the cytomorphometry of blood cells (erythrocyte, leucocyte and thrombocyte) in 10 (5♂♂, 5♀♀) adult Lycian salamanders, Lyciasalamandra fazilae, from İztuzu-Muğla, Turkey. In 1 mm3 of blood, we estimated the erythrocyte count as 1.06 x105 (0.73 x105-1.40 x105), leucocyte count as 2.14 x103 (1.60 x103–2.87 x103), haemoglobin amount as 5.00 (4.80-5.20) g/dl, hematocrit value as 36.66 (36.00-38.00)%, mean cell volume as 3281.2 (2714.3-3600.0) fl, mean cell ...
Current Zoology, 2010
Throughout the animal kingdom there are species that have two or more phenotypic forms or 'morphs', and many of these are amphibians. In North America, the red-backed salamander Plethodon cinereus can have either a red dorsal stripe or no dorsal stripe (lead-phase form), and evidence to date indicates the lead-phase form incurs a greater number of attacks from predators. In a recent collection of 51 P. cinereus, blood smears of both color morphs (35 red-stripe, 16 lead-phase) were examined to obtain numbers of circulating leukocytes (via light microscopy), which can be used to indirectly estimate levels of stress hormones in vertebrates via a 'hematological stress index', which is the ratio between the number of two leukocyte types (neutrophils and lymphocytes). Our results showed that lead-phase salamanders tended to have greater numbers of circulating neutrophils and lower numbers of circulating lymphocytes than red-stripe morphs, leading to higher average neutrophil-lymphocyte ratios in lead-phase individuals. Since the salamanders were held (refrigerated) for 7 days before sampling, we cannot be certain if this effect is a stress reaction to the captivity or the normal level for this morph. However comparison with two sets of related salamanders that were captured and sampled immediately indicates the red-stripe salamanders were either not stressed from the captivity at all, or their white blood cell distributions had returned to normal after 7 days of captivity. Taken together, our results indicate that lead-phase forms of P. cinereus have higher stress levels than the red-stripe forms, which may be a consequence of their higher exposure to, and/or attacks from, predators. They may also indicate that the lead-phase form is less-suited to captivity than the red-stripe form of this species [Current Zoology 56 (2): 238-243, 2010].
Osmotic Fragility and Erythrocyte Size in Iguana iguana (Sauria – Iguanidae) in Captivity
The erythrocyte size and osmotic fragility were studied in blood samples from adult (n = 40) and juvenile (n = 40) specimens of Iguana iguana. In fresh preparations the erythrocytes were large, oval cells. The largest diameters were 17.06 ± 2.5 mm (juvenile) and 16.20 ± 1.25 mm (adults), and the smallest diameters were 8.23 ± 1.87 mm (juvenile) and 9.00 ± 1.00 mm (adults). In fixed and stained preparations, the largest erythrocyte diameters were 15.28 ± 3.3 mm (juvenile) and 15.51 ± 1.3 mm (adults), and the smallest were 7.82 ± 0.65 mm (juvenile) and 7.85 ± 0.8 mm (adults). The haematocrit value for both juvenile and adult specimens was 27 ± 2%; the red blood cell counts were 1.3 ± 0.43610 12 /l (juvenile) and 1.2 ± 0.35610 12 /l (adults). Although no significant differences were observed in the cumulative osmotic curves, the derivative curve of adult specimens indicates the presence of at least two erythrocyte populations with osmotic fragilities at about 70 and 60 mm NaCI, representing 27% and 73% of the total cells, respectively. In samples from juvenile specimens, a major peak at about 70 mm NaCI was observed, which represented 85% of the total cell population. The difference in osmotic resistance between these erythrocyte subpopulations is correlated with their respective geometrical parameters, and compared to that of erythrocytes from other vertebrates.
Acta Herpetologica, 2013
We studied the morphology and size of erythrocytes of H. cordobae, and analysed the geographic variation of this character along the distribution of the species, in relation to the latitudinal and altitudinal distances. Erythrocyte shape of the H. cordobae is ellipsoidal and the nuclei are also ellipsoidal and centrally oriented. Erythrocyte and nuclear size showed significant differences among populations, with the highest mean size corresponding to the population of Achiras (low altitude site) and the lowest mean size to Los Linderos (high altitude site). There was no significant relationship between the latitude of each population and the both erythrocyte and nuclear size. The altitudinal variation in erythrocyte cell size may be attributable to the surface available for gas exchange; a small erythrocyte offers a possibility of greater rate of exchange than a larger one. Our results are consistent with studies of other amphibians, where intraspecific comparisons of populations at different altitudes show that individuals at higher altitudes are characterized by smaller erythrocytes.
Comparative Haematology International, 1998
The osmotic fragility and erythrocyte size were studied on 80 blood samples (40 of each) obtained from both genus Caiman species present in Argentina, maintained in captive condition in the Northeastern region of the country (Province of Corrientes). The animals were of different size, age and sex, and were fed an artificial diet for five days a week. Samples were obtained by means of venepuncture of the caudal vein or by cardiac puncture, depending on the size of the animal. The osmotic fragility test was carried out according to Dacie's method. The maximum globular resistance was proved to be 20%, the minimum 40%, and the median was 28%. The cunmlative and derivative osmotic fragility curves were constructed. No significant differences were observed in the osmotic fragility from either species or sex, nor for differing ages. In addition, the erythrocyte diameter was measured, recording the largest and smallest diameters. The largest diameter was 17.00 + 3.5 #m and the smallest 9.00 + 1.8 #m in both species. Finally, the values obtained for osmotic fragility and erythrocyte diameters were compared with other vertebrate species, especially mammals and reptiles.
The aim of this study was to determine the erythrocyte and nucleus sizes of two species of Agamidae (Laudakia nupta and Trapelus lessonae), one species of Scincidae (Mabuya aurata) and one species of Lacertidae (Ophisops elegans) from Iran by means of blood smears stained with Giemsa. The sizes of erythrocytes and their nuclei were measured using an ocular micrometer at a magnification of 6300x. The longest, widest and largest erythrocytes were found in Laudakia nupta. The shortest and narrowest erythrocytes and nuclei were found in Trapelus lessonae. The longest, widest and largest nuclei were found in Mabuya aurata. The study revealed significant variation between Iranian species and others indicating the significant affect of environmental conditions.