Biochemical targets of chick embryos affected by sub-lethal concentrations of lambda-cyhalothrin and imidacloprid

The insecticides Lambda-cyhalothrin (LCT) and imidacloprid (IMD) are extensively utilized in Egyptian agriculture. Embryonic chicken is a readily accessible model organism commonly employed in various studies. Eggs of (Gallus Gallus) chicken were immersed in an aqueous solution of two sub-lethal concentrations (0.375 and 0.0375 mg/L for LCT; 0.05 and 0.005 mg/L for IMD) for 30  sec on the fourth day of incubation of chick embryos. Significant reductions of acetylcholinesterase (AChE) activity of brain 18- and 21-day chicks were observed in the groups treated with LCT and IMD dependent on concentrations. There were significant changes (reduction or enhancement) in serum activity of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) by LCT and IMD at the used concentrations, while non-significant stimulation in the AST/ALT ratio (AAR) was found. In 18th - day embryos, the activities of glutathione S-transferase (GST) and acid phosphatase (ACP) were not significantly changed by LCT but were significantly increased by IMD. Liver alkaline phosphatase (ALP) activity showed no significant change except IMD at 0.05 mg/L. However, serum enzyme activity was significantly reduced in all groups. In addition, the tested insecticides caused notable increases in the creatinine and total protein content. The protein profile; proteins separation with sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) showed an increase in four bands that are consistent with the results of the biomarkers level. Findings indicate that even the pesticide's low concentrations are not safe and may lead to severe damage to the embryos and may lead to significant harm or developmental disruption in the embryos.