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Effects on the reproductive system in domestic dowl (Gallus domesticus) after embryonic exposure to estrogenic substances

Hermansson, Alexandra (2007). Effects on the reproductive system in domestic dowl (Gallus domesticus) after embryonic exposure to estrogenic substances. Diss. (sammanfattning/summary) Uppsala : Sveriges lantbruksuniv., Acta Universitatis agriculturae Sueciae, 1652-6880 ; 2007:20
ISBN 978-91-576-7319-0
[Doctoral thesis]

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Abstract

Environmental pollutants with estrogenic activity have a potential to disrupt oestrogen-dependent developmental processes. Thus, the aim of this thesis was to investigated how embryonic exposure to the estrogenic pollutants EE2 (17 alpha- ethynyloestradiol) and o,p´-DDT (1-[2-chlorophenyl]-1-[4-chlorophenyl]-2,2,2-trichloro-ethane) affects the reproductive system in the domestic hen (Gallus domesticus). Hens exposed in ovo to 20 or 60 ng EE2/g egg or 37 or 75 micro g o,p´-DDT/g egg produced a normal number of eggs but with thinner shells as adults. These hens also showed a reduction of shell gland capillaries with carbonic anhydrase (CA) activity. CA is considered a key enzyme in shell formation and the developmentally induced disruption of this enzyme may explain the observed eggshell thinning. Left oviduct and infundibulum was shortened in exposed hens and severely malformed in hens exposed to 150 or 300 micro g o,p´-DDT/g egg, which likely explained the inhibited egg production in these birds. Semen output was significantly reduced in both o,p´-DDT and EE2 exposed roosters, whereas sperm quality was unaffected. The left testis was deformed with an atrophied epididymis. Altered plasma inhibin concentration and histological evaluation implied a disturbed Sertoli cell function resulting in reduced germ cell production. Structural malformations in the epididymis indicating disrupted fluid transfer and transport of spermatozoa are possible contributors to the reduced semen output. Exposure to o,p´-DDT resulted in a wider range of effects than EE2 such as feminisation of the cloaca at hatch, cloacal deformation in adult roosters and a reduced comb weight, while hens showed retained right oviducts. Right spur diameter was affected by both substances.Localisation of epididymal progesterone receptors and cytoplasmic and membrane associated oestrogen receptor alfa in late spermatids, spermatozoa and epididymal tissues were novel findings in rooster. Embryonic exposure of domestic fowl to o,p´-DDT or EE2 resulted in persistent malformations of the reproductive organs of both sexes, with eggshell thinning and reduced semen production as a consequence. The results provide a possible explanation for how eggshell thinning may be induced in wild birds and show that also male birds may suffer from reduced reproductive success due to oestrogen-like pollutants.

Authors/Creators:Hermansson, Alexandra
Title:Effects on the reproductive system in domestic dowl (Gallus domesticus) after embryonic exposure to estrogenic substances
Year of publishing :April 2007
Volume:2007:20
Number of Pages:62
Papers/manuscripts:
NumberReferences
ALLI. Berg, C., Blomqvist, A., Holm, L., Brandt, I., Brunström, B., Ridderstråle, Y. 2004. Embryonic exposure to oestrogen causes eggshell thinning and altered shell gland carbonic anhydrase expression in the domestic hen. Reproduction 128, 455-61. II. Holm, L., Blomqvist, A., Brandt, I., Brunström, B., Ridderstråle, Y., Berg, C. 2006. Embryonic exposure to o,p´-DDT causes eggshell thinning and altered shell gland carbonic anhydrase expression in the shell gland in the domestic hen. Environmetal Toxicology and Chemistry 25, 2787-93. III. Blomqvist, A., Berg, C., Holm, L., Brandt, I., Ridderstråle, Y., Brunström, B. 2006. Defective reproductive organ morphology and function in domestic rooster after embryonically exposed to o,p´-DDT or ethynylestradiol. Biology of Reproduction 74, 481-6 IV. Hermansson, A., Ridderstråle, Y., Aire, T.A., Madej, A., Berg, C., Holm, L. Embryonic exposure to ethynyloestradiol or o,p´-DDT disturbs germ cell production and epididymal function of the adult domestic rooster. (Manuscript)
Place of Publication:Uppsala
ISBN for printed version:978-91-576-7319-0
ISSN:1652-6880
Language:English
Publication Type:Doctoral thesis
Full Text Status:Public
Agrovoc terms:layer chickens, cocks, oviducts, carbonate dehydratase, oestrogens, reproduction, progesterone, testes, semen, egg shell, quality, reproductive disorders, pollutants, environmantal impact
Keywords:carbonic anhydrase, cloaca, comb, eggshell, EE2, embryonic exposure, epididymis, oestrogen, oestrogen receptor alpha, o, p´-DDT, oviduct, progesterone receptor, semen output, Sertoli cell, shell gland, sperm transport, spur, testis.
URN:NBN:urn:nbn:se:slu:epsilon-1542
Permanent URL:
http://urn.kb.se/resolve?urn=urn:nbn:se:slu:epsilon-1542
ID Code:1375
Department:(VH) > Dept. of Anatomy, Physiology and Biochemistry
Deposited By: Alexandra Hermansson
Deposited On:26 Apr 2007 00:00
Metadata Last Modified:02 Dec 2014 10:11

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