Birds are the first victims of exposure to toxic chemical agents through all ecosystems, so that it is very interest to study the xenobiotic biotransformation in birds. However, environment is continuously loading by several thousands of organic pollutants by many ways, which released into the environment by industrialization. β-methylcholanthrene (MC) is one of the polycyclic aromatic hydrocarbon (PAH), an experimental carcinogenic agent. The present study aimed to understand the adverse influence of MC on chick embryo brain glutathione S-transferase (GSTs). In this study, chick embryo was administered by MC and evaluates the expressed brain GSTs. That GST isoenzymes were screened with model substrates; specific activities of them were increased in response to 2 ppm and 4 ppm MC, and decreased in response to 6 ppm MC. At histological level, 6 ppm MC administered brain cerebellar layers degeneration, molecular layer expansion towards granular layer and vacuolation were noticed in 24 hours interval; severe cerebral haemorrhage and vacuolation were noticed in 48 hours interval. So that, MC is a potent neurotoxin for developing chick embryo and care should be need to produce healthy poultry.
Key words: β-methylcholanthrene, chick embryo, glutathione S-transferses, western blot, brain degeneration.