Toxicological effects of trichlorfon on hematological and biochemical parameters in Cyprinus carpio L. following thermal stress.

Trichlorfon is a moderately toxic organophosphate pesticide that is widely used in aquaculture. This study investigated the effects of trichlorfon on hematological parameters, biochemical factors, and stress reaction in Cyprinus carpio L. The fish were exposed to acute concentrations of trichlorfon (0, 0.5, 1.0, 2.0, and 4.0 mg L-1) at 25 °C and 15 °C for 1 and 2 weeks, after which several parameters were evaluated to assess the effects of the pesticide. Significant decreases were observed in red blood cell (RBC) Count, hemoglobin (Hb) level, hematocrit (Ht), and plasma protein levels after each exposure period. In contrast, notable increases in mean corpuscular volume (MCV), mean cell hemoglobin (MCH), calcium, and glucose levels were observed in the trichlorfon-treated groups. Additionally, there were significant increases in the plasma levels of glutamate-oxaloacetate transaminase (GOT), glutamate-pyruvate transaminase (GPT), and alkaline phosphatase (ALP) following the exposure to trichlorfon. Furthermore, the results showed a relationship between toxic stress and increment in HSP70 and cytochrome P450 1A (CYP1A) expression over time. Ht, MCV, MCH, and the value of other biochemical parameters were quite lower at 15 °C than their corresponding values were at 25 °C, which indicated the decreased physical activity at 15 °C. The results of the present work indicate that acute exposure to trichlorfon and thermal stimulus could damage erythropoietic tissue. Additionally, hepatocytes function and physiological mechanisms could be impaired. Ht, glucose, GOT, GPT, HSP70, and CYP1A levels might be useful biomarkers of trichlorfon toxicity in contaminated aquatic ecosystems.

The toxic effects of ammonia exposure on antioxidant and immune responses in Rockfish, Sebastes schlegelii during thermal stress.

Rockfish, Sebastes schlegelii (mean weight 14.53 ± 1.14 cm, and mean weight 38.36 ± 3.45 g) were exposed for 4 weeks (2 weeks and 4 weeks) with the different levels of ammonia in the concentrations of 0, 0.1, 0.5, 1.0mg/L at 19 and 24°C. The ammonia exposure induced significant alterations in antioxidant responses. The activities of SOD, CAT, and GST were considerably increased by the ammonia exposure depending on water temperature, whereas the GSH level was notably decreased after 2 and 4 weeks. In the stress indicators, the cortisol and HSP 70 were significantly elevated by the exposure to ammonia depending on water temperature. In innate immune responses, the phagocytosis and lysozyme activity were notably decreased by ammonia exposure depending on water temperature after 2 and 4 weeks. The results suggest that ammonia exposure depending on water temperature can induce the considerable alterations in antioxidant responses, stress, and immune inhibition.