Response of broiler chickens to low level intake of polychorinated biphenyl isomers

Commercial-type broiler starter and finisher feeds containing 0, .1, 1.0, 5.0, 10.0, or 20.0 ppm of polychlorinated biphenyl isomers (PCBs) as Aroclor 1254 (Monsanto) were fed to male broiler chicks (Arbor Acres 70 X Cobb) from hatching to 8 weeks of age. Feed intake and body weights were recorded on a weekly basis. The birds were killed at 8 weeks of age and samples of leg and breast muscle and adipose tissue were removed from each bird for PCBs analysis by gas chromatography (Pesticide Anal. Manual, FDA, '74). Linear log-log dose response curves with confidence limits were fitted to all data. There was a progressive, significant reduction in growth in response to increasing levels of PCBs fed. PCBs toxicity symptoms were seen at 10 and 20 ppm levels. All tissues showed significant, progressive accumulations of PCBs in response to increased dose.