Biological activity of technical Aroclor 1254 compared to Aroclor 1254 residues: Swine fat residues fed to boiler cockerels

Fat from Aroclor 1254-treated swine was rendered and incorporated into the diets of broiler chicks for 3–4 weeks. The technical Aroclor 1254 which was fed to the swine was also mixed into control lard for comparison at dietary concentrations of 0.07–9.0 mg/kg. The swine-residue PCB seemed to have a higher proportion of strong microsomal inducers, but the technical PCB was slightly more effective in inducing ethoxy resorufin and $\text{p-}\text{nitroanisole}$ (pNA) $\text{O-}\text{dealkylases}$ than the swine-residue PCB. No overt signs of toxicosis were apparent and one of the diets resulted in changes in growth, relative organ weights, microsomal protein or high affinity pNA $\text{O-}\text{dealkylase}$. Increases in cytochrome(s) $\text{P-450}$ were significant only at the higher dietary concentrations (approx. 9 mg/kg) while ethoxyresorufin $\text{O-}\text{dealkylase}$ was induced at dietary concentrations below 1 mg/kg.