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Background: The European hake ( Merluccius merluccius ) is a commercially valuable demersal species widely distributed in the Mediterranean Sea. Assessing the condition of fish populations in their natural habitats is challenging due to the lack of reliable reference points., Objective: This study aimed to utilize hematological analysis as an economical method to evaluate the physiological and health status of European hake, addressing the gap in hematological data for this species., Methods: Blood samples were collected from the caudal vein of 40 adult European hakes caught from the Toroneos Gulf (northern Greece) using a commercial bottom otter trawl. An automated hematological analyzer was used to assess hematological parameters alongside biometric and biological indices., Results: Female hakes showed significantly higher white blood cell (WBC) counts, thrombocyte (TC) counts, and red cell distribution width (RDW) than their male counterparts. Strong correlations were observed among various hematological parameters, notably between WBC and red blood cells (RBCs), hematocrit (Ht), and hemoglobin (Hb); between RBC and both Ht and Hb; between TC and both mean platelet volume and platelet distribution width (PDW); and between mean corpuscular Hb concentration and RDW. Significant differences were noted in RBCs, Hb, and Ht compared to data from wild-caught European hake populations in Argentina and Denmark. Both trawling depth and duration were found to significantly affect RBC, WBC, Hb, and Ht values, while having no notable impact on TC. Fish captured at an average depth of 80 m and with a trawling duration of 30 min exhibited significantly elevated hematological indices., Conclusion: This study demonstrates that hematological analysis is a valuable, cost-effective tool for assessing the physiological and health status of European hake populations in the Mediterranean. Notable differences in hematological parameters based on sex, as well as significant correlations among key blood metrics, underscore the importance of understanding species-specific hematological profiles. The influence of trawling depth and duration on certain blood parameters highlights the need for standardized sampling protocols in population health assessments. These findings contribute essential baseline hematological data for European hake, facilitating more informed fisheries management and conservation strategies., Competing Interests: The authors declare no conflict of interest. The funders had no role in the design of the study in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results., (© 2024 The Journal of Biological Methods, All rights reserved.)

The impact of fish farming on the physicochemical and biological parameters of the water column was investigated between July and October 2021, in Pagasitikos Gulf. For this purpose, a sampling strategy based on Geographical Information System (GIS) was developed and a grid of 28 sampling stations was created for in situ measurements. The method of spatial interpolation and especially the Radial Basis Function (RBF) was used to estimate the spatial distribution of DO, chl α and nutrients by means of GIS. General Linear Model (GLM) analysis showed significant differences for all measured parameters except for NO 3 . Nutrients remained at low concentrations without exceeding the permitted limits for eutrophication and welfare of cultivated organisms. GIS exhibited high usefulness for data analysis, with further studies warranted for its optimization on applications related to the environmental impact of fish farming., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Sixty-four samples from the groundwater resources of Trikala municipality, central Greece, were collected during two periods (2006 and 2007) and analyzed for physico-chemical parameters (temperature, pH, specific electrical conductivity, and total dissolved solids), major ions (Ca(2+), Cl(-), HCO(3)(-), K(+), Mg(2+), Na(+), NO(3)(-), SO(4)(2-)), and several potentially toxic elements (Al, B, Ba, Br, Ca, Ce, Cl, Cr, Cu, Fe, K, La, Li, Mg, Mn, Mo, Na, Nd, Ni, P, Pb, Rb, S, Sc, Si, Sn, Sr, U, V, Y, Zn). European Council directives and USEPA guidelines were used to assess the water quality. The results indicate that all samples are fresh water, suitable for human consumption. All basic ions and physico-chemical parameters have average concentrations below their recommended optimum limits with the exception of electrical conductivity, for January 2007, and nitrate for October 2006 and January 2007 sampling periods. This exceedance is the result of dissolution of minerals such as calcite and dolomite that are present in the surrounding rocks and the application of fertilizers, respectively. Lead is the only element with an average value that exceeds the recommended EC guideline, while special attention should be paid to one borehole (T9) which has elevated NO(3)(-) values which may pose a risk to human health.