Histopathological Changes in Estuarine Catfish: A Temporal Approach in a Marine Protected Area

Abstract

The Cananéia-Iguape Estuarine-Lagoon Complex (CIELC) is an area of low anthropogenic impact; however, it is not completely isolated from human pressure, particularly in the northern sector. Considering this scenario, this study aims to identify the health of two catfish species Cathorops spixii and Genidens Genidens taking into account the hepatic pathological analysis and the accumulation of iron in the form of hemosiderin considering a temporal approach. Biometric measurements were taken, and the condition factor was obtained. The main liver alterations found in the two catfish species were necrosis, inflammation, hemorrhage, cytoplasmatic vacuolization, and pyknosis nuclei. Necrosis (2014: 57%; 2017: 71 %; and 2018: 20%) and pyknosis nuclei (2014: 86%; 2017: 43%; and 2018: 40%) was the most frequent alteration. However, cytoplasmatic vacuolization was the only change that was statistically significant over time. Regarding hemosiderin, catfish livers mostly presented a minimum degree of accumulation, which represents healthy results. Finally, histopathological observations in C. spixii and G. genidens catfish tissues are confirmed to be an efficient tool to evaluate the health of these fish and the changes induced by environmental conditions over the years. However, the absence of significant differences on the histopathological changes over time can suggest a physiological equilibrium of these fish in the CIELC.

Keywords:
Biomarker; Cathorops spixii ; Genidens genidens ; Biomonitoring; Cananéia

HIGHLIGHTS

Hepatic changes in catfish bioindicator were effectiveness to indicate the ecosystem health.

Human risk to resident fish population must monitored.