Carica papaya and Mangifera indica modulate haematological, biochemical and histological alterations in atrazine-intoxicated fish, Clarias gariepinus (Burchell 1822)

Abstract

Abstract Background Atrazine has impacted negatively on fish by inducing significant alterations in their haematological, biochemical and histological parameters. Mitigating such alterations to enhance fish survival becomes pertinent. Unfortunately, readily available and eco-friendly remedies are scarce. The study, therefore, investigated the potential ameliorative effects of dietary supplementation of aqueous Carica papaya and Mangifera indica leaf extracts on atrazine-induced toxicity and oxidative damage in the tissues of Clarias gariepinus. Fish (average weight: 10.57 ± 1.69 g, and average length: 10. 36 ± 1.26 cm) were randomly divided into six groups of ten samples each. Group I served as control and administered borehole water only, group II was exposed to 8.50 µg/l atrazine corresponding to ¼ of 96 h LC50, group III was treated with low (0.25 mg/g) concentration of each extract alone, group IV was exposed to 8.50 µg/l atrazine and treated with the low concentration of each extract, group V was administered with high (0.75 mg/g) concentration of each extract alone, and group VI was exposed to 8.50 µg/l atrazine and treated with the high concentration of each extract. The experiment spanned 28 days after which the haematological, biochemical and histopathological alterations were assayed. Results Atrazine intoxication significantly induced oxidative damage in the gill and liver, culminating into different histopathological disorders, decreased haematological parameters, increased serum, gill and liver levels of malondialdehyde and enzyme biomarkers (alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and acetylcholinesterase). On the other hand, atrazine exposure caused decreased levels of glucose, protein and superoxide dismutase in the tissues. Treatment with diets fortified with both extracts significantly increased all the decreased haematological parameters, reduced the serum levels of the elevated malondialdehyde and tissues enzyme biomarkers in a concentration-dependent manner. Biochemical parameters in the tissues were also improved with dietary supplementation of the extracts. Histopathological examination of both tissues showed ameliorating effects of both extracts in restoring the structural and functional integrity of each tissue. Conclusions These results suggest that the extracts have ameliorative potentials against atrazine-induced peroxidative injury in C. gariepinus. The utilisation of these extracts could enhance better health management practices, particularly in a rice-cum fish culture, where atrazine application is common.