The goal of this study was to examine the effect of oxidative stress (OS) induced with hydrogen
peroxide (H2O2) on the anaesthetic properties of ketamine in seven and 14 day-old broiler chicks. Spectrophotometric
analysis revealed that H2O2 (0.5%) induced OS through significant inhibition of glutathione (GSH) and
elevation of malondialdehyde (MDA) concentrations in the brain of chicks in comparison to control (tap water)
group. The hypnotic and analgesic median effective doses (ED50s) decreased by 44% and 19%, respectively, in the
stressed group compared to control group of chicks. On the other hand, the acute toxicity of ketamine increased
through decreasing the acute median lethal dose (LD50) (22%) in stressed chicks as determined by the up-anddown
method. Injection of multiple ketamine doses at 10, 20 and 40 mg/kg, i.m. produced hypnotic effects for
both groups of chicks depending on the dose, whereas H2O2 caused an increase in ketamine hypnotic efficacy
in comparison to the control group. In the same manner, the antinociceptive effect of ketamine increased in the
stressed chicks that underwent electrostimulation for pain induction. Both AST and ALT concentrations in the
plasma were significantly elevated in the stressed group when compared to the control group. The results of this
study suggest that H2O2-induced OS modifies the anaesthetic properties of ketamine in chicks by increasing its
efficacy and acute toxicity probably through its pharmacodynamic and pharmacokinetic interactions; thus, care
must be taken when stressed animals are undergoing anaesthesia with ketamine.
يعرب جعفر موسى | Yaareb Jaafar Mousa | 5707