Biomarcadores histopatológicos na espécie Hoplias malabaricus (Pisces, Osteichthyes, Erythrinidae) em uma Unidade de Conservação de São Luís (MA)

Abstract

RESUMONeste estudo objetivou-se validar dois órgãos (brânquia e fígado) de Hoplias malabaricus para análise de biomarcadores de contaminação aquática na Área de Proteção Ambiental (APA) do Maracanã em São Luís-MA. Exemplares de traíra foram capturados em uma lagoa de policultivo e no Rio Ambude, localizados na APA do Maracanã. A biometria foi realizada em laboratório. Brânquias e o fígado de cada espécime foram fixados em formol a 10% e mantidos em álcool a 70% até a execução da técnica histológica usual. Cortes de aproximadamente 5µm de espessura foram corados em hematoxilina e eosina (HE). Os resultados referentes à biometria dos peixes capturados durante o período de estiagem indicaram que o comprimento total e padrão dos exemplares foram maiores quando comparados com os indivíduos do período chuvoso. As alterações hepáticas identificadas foram: lipidose, necrose, infiltração leucocitária, vacuolização do citoplasma, hemossiderina e centro de melanomacrófagos. Constataram-se as seguintes lesões branquiais: fusão lamelar, aneurisma lamelar, deslocamento e necrose do epitélio, proliferações de células do muco e dilatação capilar. As respostas biológicas de H. malabaricus, registradas em nível branquial e hepático, podem ser caracterizadas como biomarcadores de contaminação aquática. As brânquias mostraram-se como os melhores órgãos para esse tipo de análise na espécie. Esses resultados indicam que os peixes da região apresentam a saúde comprometida por poluentes presentes nos ambientes analisados. Palavras-chave: biomarcadores, lesões histológicas, monitoramento ambiental ABSTRACT The aim of the present work was to validate two organs (liver and gill) of Hoplias malabaricus for analysis of aquatic contamination biomarkers in the Maracanã Environmental Protected Area (APA) in

Histopathological and hematological biomarkers in tambaqui Colossoma macropomum (Cuvier, 1816) from an environmental protection area of Maranhão, Brazil

“…Fortes Carvalho Neta et al (2015) affirm that pollution in this region has intensified in recent years, both by the agropastoral systems and by the large industries installed around this Environmental Protection Area, causing serious problems in the aquatic environment, such as the decrease of dissolved oxygen, temperature oscillation, lack of nutrients and also the eutrophication of these environments. Our results are in agreement with the data found by Fortes Carvalho Neta et al (2015) and Castro et al (2014) and indicate that all these problems can cause stress to the fish and cause changes in their morphological structures, such as the severe branchial lesions found in the specimens analyzed in the Ambude River. Studies performed by Nogueira et al (2008), using the species Pimelodus maculatus captured in the Furnas-MG reservoir (Brazil), identified the following lesions: aneurysm, cell proliferation in the secondary lamella and branchial filament, epithelial displacement in the branchial filament, hypertrophy, blood congestion in the marginal bloodstream and lamellar fusion; these injuries are related to the development of agricultural activities that are being carried out near the reservoir banks, contributing to an increase in the entrance of fertilizers and raw sewage in several areas.…”

“…The fish from the Ambude River presented the highest percentage of branchial alterations; this factor could be related to the leaching process of the pollutants, which are carried by the rain to the rivers. Castro et al (2014) when analyzing the H. malabaricus species collected in the same region, identified lesions similar to those found in this study.The authors suggest the hypothesis that such lesions were caused by the release of rural and industrial effluents in the aquatic bodies of this region. Fortes Carvalho Neta et al (2015) affirm that pollution in this region has intensified in recent years, both by the agropastoral systems and by the large industries installed around this Environmental Protection Area, causing serious problems in the aquatic environment, such as the decrease of dissolved oxygen, temperature oscillation, lack of nutrients and also the eutrophication of these environments.…”

“…In addition, this species is considered a bioindicator due to the ease of handling and maintenance in the laboratory and has been used to evaluate the quality of aquatic environments (Fortes Carvalho Neta et al, 2015). A study carried out by Castro et al (2014) revealed that the use of biomarkers in fish is efficient in support of public bodies' decisions, in order to carry out monitoring actions in these environments.…”

Evidence of cytogenetic and histological damage in specimens of Astyanax lacustris (Pisces, Characidae) exposed to the hydrogen cyanide-based herbicide Dormex®

“…Lamellar edemas (aneurysms) were also observed, albeit less frequently, in the gills of all the specimens exposed to Dormex ® (Figure 4D). The histopathological effects of pesticides on fish have been studied widely, and include alterations to the gills, liver, blood vessels, and kidney (Castro, Silva, Freitas, & Carvalho-Neta, 2014;El-Sharaby et al, 2018;Velmurugan, Cengiz, Yolcu, Uğurlu, & Selvanayagam, 2020). In fish, the gills initially respond through hyperplasia, which results in increased cell and tissue function, caused by physiological changes (Takashima & Hibiya, 1995).…”

Evaluation of aquatic contamination in an urban lagoon environment in a coastal region in the north of Brazil

“…The secretion of mucus by the mucosal cells in the gills is known to be a defense mechanism against toxic substances (BOSI et al, 2005, COVELLO et al, 2009, MARCATO et al, 2014. Mucosal cell proliferation has been observed in different species of fish exposed to metal and herbicide contamination in situ (PAULINO et al, 2012;2014).…”