title: Effects of 3,3',4,4',5-pentachlorobiphenyl (PCB 126) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) injected into the yolks of chicken (Gallus domesticus) eggs prior to incubation.
abstract: The yolks of White Leghorn chicken (Gallus domesticus) eggs were injected prior to incubation with either 3,3',4,4',5-pentachlorobiphenyl (PCB 126) at doses ranging from 0.1 to 12.8 microg/kg egg or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) at doses ranging from 0.04 to 0.64 microg/kg egg. Chicks were subjected to necropsy within 24 h of hatching. The brain, bursa, heart, liver, and spleen were removed and weighed. Assessment of the rate of hatching indicated an LD50+/-S.E. of 2.3+/-0.19 microg/kg egg (7. 1+/-0.58 nmol/kg egg) for PCB 126 and 0.15 +/- 0.012 microg/kg egg (0.47 +/- 0.037 nmol/kg egg) for TCDD. No significant differences in the incidence of developmental abnormalities (structural defects and edema) were observed in TCDD-exposed embryos, while PCB 126 caused significantly more developmental abnormalities at 3.2, 6.4, and 12.8 microg/kg egg than the vehicle control. PCB 126 caused lower hatchling weights and greater relative brain, heart, and liver weights when compared to the vehicle control group at a dose of 3.2 microg/kg egg which is greater than the LD50. TCDD at 0.08 microg/kg egg caused relative bursa weights to be less than those of the vehicle control. A toxic equivalency factor (TEF) of 0.07 was determined for PCB 126 in relation to TCDD based on overt lethality.
authors.affiliation: Department of Animal Science, Michigan State University, East Lansing, Michigan 48824, USA.
authors.forename: D C
authors.initials: DC
authors.lastname: Powell
authors.forename: R J
authors.initials: RJ
authors.lastname: Aulerich
authors.forename: J C
authors.initials: JC
authors.lastname: Meadows
authors.forename: D E
authors.initials: DE
authors.lastname: Tillitt
authors.forename: J P
authors.initials: JP
authors.lastname: Giesy
authors.forename: K L
authors.initials: KL
authors.lastname: Stromberg
authors.forename: S J
authors.initials: SJ
authors.lastname: Bursian
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D002060:Bursa of Fabricius / Q000187:drug effects / Q000378:metabolism; D002642:Chick Embryo; D002645:Chickens; D004305:Dose-Response Relationship, Drug; D004530:Egg Yolk / Q000187:drug effects* / Q000378:metabolism; D005314:Embryonic and Fetal Development / Q000187:drug effects*; D005315:Fetal Diseases / Q000401:mortality; D006321:Heart / Q000187:drug effects; D007928:Lethal Dose 50; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D009929:Organ Size / Q000187:drug effects; D011078:Polychlorinated Biphenyls / Q000008:administration & dosage / Q000633:toxicity*; D000072317:Polychlorinated Dibenzodioxins / Q000008:administration & dosage / Q000633:toxicity*; D013329:Structure-Activity Relationship
chemical_list: D000072317:Polychlorinated Dibenzodioxins; D011078:Polychlorinated Biphenyls; C023035:3,4,5,3',4'-pentachlorobiphenyl