Differences in Response of Caged White Leghorn Layers to Various Polychlorinated Biphenyls (PCBs) in the Diet

The PCBs tested with caged White Leghorn hens were Aroclors 1221, 1232, 1242, 1248, 1254, 1268, 5542 and BP-6 fed at the 20 p.p.m. level. In addition, 1242, 1248 and 1254 were also fed at the 2 p.p.m. level. None of these pollutants exerted any adverse effects on adult body weight gain, livability, egg weight, egg shell thickness or fertility after 9 weeks of PCB feeding. Egg production was significantly reduced by 1232, 1242, 1248, 1254 and BP-6, all at the 20 p.p.m. level. Feed consumption per hen-day was significantly reduced by 20 p.p.m. 1242, 1248, 1254 and BP-6. Hatchability of fertile eggs was significantly affected by the 20 p.p.m. level of 1232, 1242, 1248 and 1254; the hatchability of eggs laid by hens fed 20 p.p.m. 1248 declined to 1.8% by the 9th week of feeding, as compared with 95% for the control group. Progeny growth was significantly depressed by the feeding of 1232, 1242, 1248, 1254 and BP-6 in the maternal diet; only one PCB (Aroclor 1248) in the maternal diet produced a significant increase in mortality of progeny.