Qualitative characteristics of blood cells and evaluation of hematological parameters in Trichomycterus areolatus (Valenciennes, 1846) and Percilia gillissi (Girad, 1854) exposed to pulp mill effluent in the Itata River (Chile)

摘要

Ichthyohematology is a great tool to assess the physiological changes, as we could use the study of morphological, biochemical and functional differences of the several cell lines, as well as the hematopoietic organs and the diseases related to those responses. The study analyzed through relative count and morphometric characterization, the three blood lines, erythrocytes, leukocytes and trombocytes in two wild freshwater fish species populations (Trichomycterus areolatus & Percilia gillisssi), collected during summer 2009 in four sites upstream and three sites downstream a pulp mill effluent discharge in the Itata River (Biobio Region, Chile). As part of the study we calculated and assessed the fish condition factor, as general health status condition index. The results showed that the morphological characteristics of the blood lines of T. areolatus y P. gillissi are equivalent to the described characteristics of other teleosts. Condition Factor and the immature erythrocytes showed a significative reduction in the first site downstream the pulp mill effluent discharge for both species. On the other hand, significative increment on leukocytes and trombocytes were observed, showing possible immunological alterations. The hematological assessment for native fish shows no major differences in morphological characteristics from other teleosts and observed results in the three blood lines might be evidence of a possible anemia, along with immune alterations that might affect the condition factor downstream of the pulp mill effluent discharge, resulting in a stressed wild fish population.