Sensitivity of Japanese quail (Coturnix japonica), Common pheasant (Phasianus colchicus), and White Leghorn chicken (Gallus gallus domesticus) embryos to in ovo exposure to TCDD, PeCDF, and TCDF.
Egg injection studies were performed to confirm a proposed model of relative sensitivity of birds to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). In this model, species are classified as belonging to one of three categories of sensitivity based on amino acid substitutions in the ligand-binding domain of the aryl hydrocarbon receptor. Embryo lethality and relative potencies of 2,3,7,8-tetrachlorodibenzofuran (TCDF) and 2,3,4,7,8-pentachlorodibenzofuran (PeCDF) were compared with TCDD for Japanese quail (Coturnix japonica; least sensitive), Common pheasant (Phasianus colchicus; moderately sensitive), and White Leghorn chicken (Gallus gallus domesticus; most sensitive). Doses ranging from 0.044 to 37 pmol/g egg (0.015-12 ng/g egg) were injected into the air cell of eggs prior to incubation. LD(50) (95% confidence intervals) values, based on rate of hatching for TCDD, PeCDF, and TCDF, were 30 (25-36), 4.9 (2.3-9.2), and 15 (11-24) pmol/g egg for the quail, 3.5 (2.3-6.3), 0.61 (0.28-1.2), and 1.2 (0.62-2.2) pmol/g egg for pheasant, and 0.66 (0.47-0.90), 0.75 (0.64-0.87), and 0.33 (0.23-0.45) pmol/g egg for chicken, respectively. LD(50)-based relative potencies of PeCDF and TCDF were 6.1 and 2.0 for quail, 5.7 and 2.9 for pheasant, and 0.88 and 2.0 for chicken, respectively. TCDD was not the most potent compound among the species tested, with PeCDF and TCDF being more potent than TCDD in the quail and pheasant. TCDF was the most potent in chicken. Species sensitivity was as expected for TCDD and TCDF, whereas for PeCDF, the chicken and pheasant were similar in sensitivity and both were more sensitive than the quail. Results from companion in vitro studies are generally similar to those reported here with a few exceptions.
Cohen-Barnhouse
Andrew M
AM
Department of Animal Science, Michigan State University, East Lansing, Michigan 48824, USA.
Zwiernik
Matthew J
MJ
Link
Jane E
JE
Fitzgerald
Scott D
SD
Kennedy
Sean W
SW
Hervé
Jessica C
JC
Giesy
John P
JP
Wiseman
Steve
S
Yang
Yinfei
Y
Jones
Paul D
PD
Wan
Yi
Y
Collins
Brian
B
Newsted
John L
JL
Kay
Denise
D
Bursian
Steven J
SJ
D000818:Animals; D001572:Benzofurans / Q000633:toxicity*; D002642:Chick Embryo; D002645:Chickens / Q000254:growth & development; D003370:Coturnix / Q000196:embryology / Q000254:growth & development; D004625:Embryo, Nonmammalian / Q000187:drug effects* / Q000473:pathology; D046094:Galliformes / Q000196:embryology / Q000254:growth & development*; D007928:Lethal Dose 50; D008954:Models, Biological; D010063:Ovum / Q000187:drug effects*; D000072317:Polychlorinated Dibenzodioxins / Q000633:toxicity*; D013045:Species Specificity; D018675:Toxicity Tests
D001572:Benzofurans; D000072317:Polychlorinated Dibenzodioxins; C038890:2,3,4,7,8-pentachlorodibenzofuran; C014211:2,3,7,8-tetrachlorodibenzofuran