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Zhelev Z.M.,Plovdiv University | Popgeorgiev G.S.,Bulgarian Society for the Protection of Birds BSPB Birdlife Bulgaria | Mehterov N.H.,Medical university-Plovdiv
Acta Zoologica Bulgarica | Year: 2015

Basic haematological parameters such as erythrocyte count, leukocyte count, haemoglobin concentration, haematocrit value, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, mean corpuscular volume, and differential blood formula of adults, of Pelophylax ridibundus from the Studen Kladenets Reservoir near the Lead and Zink Plant "Kardzhali" were studied. The data were compared with those of populations from biotopes with various levels of anthropogenic pollution in Southern Bulgaria. Based on the results, an evaluation of the ecological status of the Studen Kladenets Reservoir was made. The information value of the haematological parameters as bioindicators was confirmed by a general assessment of changes occurring in P. ridibundus populations from polluted biotopes, which showed specificity depending on the type and concentration of toxic agents. © 2015, Bulgarian Academy of Sciences. All rights reserved. Source


Zhelev Z.M.,Plovdiv University | Mehterov N.H.,Medical university-Plovdiv | Popgeorgiev G.S.,Bulgarian Society for the Protection of Birds BSPB Birdlife Bulgaria
Ecotoxicology and Environmental Safety | Year: 2016

The purpose of this research work is to present data that show the seasonal changes (spring-summer-autumn) of basic erythrocyte-metric parameters (Ye{cyrillic}L: Erythrocyte length, Ye{cyrillic}W: Erythrocyte width, Ye{cyrillic}L/Ye{cyrillic}W, ES: Erythrocyte size; NL: Nucleus length, NW: Nucleus width, NL/NW; NS: Nucleus size, NS/ES: Nucleus-cytoplasmic ratio) in Pelophylax ridibundus populations from three biotopes located on two rivers in Southern Bulgaria (less disrupted biotope, with domestic sewage pollution and heavy metal pollution). Differences of high statistical significance were found among the different populations. Within the population living in conditions of domestic sewage pollution, for the entire period of the investigation the erythrocytes and their nuclei had an elliptical shape (a slight elongation of ellipses in autumn) and the biggest sizes (EL, EW, ES, NL and NS were constantly higher than the less disrupted biotope), NS/ES, became significantly smaller in autumn. Throughout the period of investigation, the values of all nine cellular and nuclear parameters were statistically-significantly the lowest in the population from the biotope with heavy metal pollution. The parameters: EL, Ye{cyrillic}W, NL, NW and ES became significantly lower, progressively and statistically, during seasonal transitions. Cells and nuclei grew ovular in shape in comparison to the populations from the other two biotopes (this process was most pronounced in autumn) and NS/ES numbers were significantly decreased in summer and autumn. © 2015 Elsevier Inc. Source


Zhelev Z.M.,Plovdiv University | Popgeorgiev G.S.,Bulgarian Society for the Protection of Birds BSPB Birdlife Bulgaria | Arnaudov A.D.,Plovdiv University | Georgieva K.N.,Medical university-Plovdiv | Mehterov N.H.,Medical university-Plovdiv
Archives of Biological Sciences | Year: 2015

The aim of this study was to investigate the integral indicator for developmental stability, the fluctuating asymmetry (FA), in the marsh frog Pelophylax ridibundus populations that inhabit biotopes of different types (running rivers and still, dam lakes), when exposed to different types of anthropogenic pollution (domestic sewage pollution and heavy metal pollution) in south Bulgaria. A total of 920 P. ridibundus individuals were used for FA analyses over three years (2009-2011). Fluctuating asymmetry was defined by 10 morphological traits, using the index frequency of asymmetric manifestation of an individual (FAMI). In closed water basins, regardless of the nature of toxicants, the FA values in P. ridibundus populations were statistically lower than those in river populations. The FA values were constantly the highest under conditions of sustained anthropogenic pollution, with high concentrations of toxicants in rivers with domestic sewage pollution and heavy-metal pollution. The results provide better opportunities to use FA in P. ridibundus populations for bioindication and biomonitoring, and for parallel and independent analyses of the physicochemical assessment of the environmental condition. Source

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