{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/23286"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/23286","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"The physiological role of relaxin in the pregnant gilt: The effects of relaxin on the physical and biochemical properties of the cervix and on mammary development in ovariectomized hormone-treated pregnant gilts","abstract":"The purpose of this research was to determine the physiological roles of relaxin in pregnant gilts by ovariectomizing gilts during the last third of gestation followed by hormone replacement therapy. Nara and coworkers demonstrated that in pigs ovariectomized in late pregnancy a prolonged delivery and a low incidence of live births occurred in the absence of relaxin replacement. Eldridge-White and coworkers demonstrated that in intact pregnant pigs beginning about day 80 of pregnancy and continuing until term, cervical extensibility and size increased coinciding with rising relaxin and estrogen levels.","abstract_html":"The purpose of this research was to determine the physiological roles of relaxin in pregnant gilts by ovariectomizing gilts during the last third of gestation followed by hormone replacement therapy. Nara and coworkers demonstrated that in pigs ovariectomized in late pregnancy a prolonged delivery and a low incidence of live births occurred in the absence of relaxin replacement. Eldridge-White and coworkers demonstrated that in intact pregnant pigs beginning about day 80 of pregnancy and continuing until term, cervical extensibility and size increased coinciding with rising relaxin and estrogen levels.","abstract_has_math":false,"creators":["Bowman, Mary Bridget"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Molecular and Integrative Physiology","degree_department":null,"school":null,"contributors":["Sherwood, O. David"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T14:08:46Z","date_published":"2011-05-07T14:08:46Z","updated_at":"2026-07-22T22:25:21Z","subjects":["Biology, Animal Physiology"],"languages":["eng"],"rights":["Copyright 1991 Bowman, Mary Bridget"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9136549","(UMI)AAI9136549"],"render_values":[{"text":"AAI9136549","href":null,"code":true},{"text":"(UMI)AAI9136549","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/23286","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Sherwood, O. 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Nara and coworkers demonstrated that in pigs ovariectomized in late pregnancy a prolonged delivery and a low incidence of live births occurred in the absence of relaxin replacement. Eldridge-White and coworkers demonstrated that in intact pregnant pigs beginning about day 80 of pregnancy and continuing until term, cervical extensibility and size increased coinciding with rising relaxin and estrogen levels.","In the first study I explored the hypothesis that the deleterious effects on birth seen in the absence of relaxin were, at least partially, attributable to a failure of the cervix to grow and soften. This study demonstrated that in ovariectomized pregnant pigs increases in extensibility and growth of the cervix occurred only in the presence of relaxin. The second study demonstrated that the growth and softening of the cervix promoted by relaxin in ovariectomized pregnant pigs is accompanied by a decrease in collagen concentration and increases in water content, dry weight, and the glycosaminoglycan:collagen ratio. These results support the hypothesis that relaxin-induced changes in cervical connective tissue components may account, in part, for relaxin's effects on cervical extensibility, cervical growth and normal birth in pigs.","The third study examined relaxin's influence on mammary gland development. In ovariectomized pregnant pigs, growth of the mammary parenchymal tissue during the last third of gestation occurred only with relaxin administration. These results suggest that relaxin' s stimulation of mammogenesis may be important for normal lactation in pigs.","In conclusion, this research demonstrates two important physiological roles for relaxin during pregnancy in pigs. Relaxin promotes increased cervical extensibility and growth, as well as, mammary gland development.","Made available in DSpace on 2011-05-07T14:08:46Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9136549.pdf: 5662857 bytes, checksum: 94b6b3c5e4cda62f612d8dc8e5a0f0f3 (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:03:27Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:30:14-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"]},{"key":"dc:title","label":"Title","values":["The physiological role of relaxin in the pregnant gilt: The effects of relaxin on the physical and biochemical properties of the cervix and on mammary development in ovariectomized hormone-treated pregnant gilts"]}]}],"canonical_facts":{"dc:contributor":["Sherwood, O. David"],"dc:creator":["Bowman, Mary Bridget"],"dc:date":["2011-05-07T14:08:46Z","10000-01-01","1991"],"dc:description":["The purpose of this research was to determine the physiological roles of relaxin in pregnant gilts by ovariectomizing gilts during the last third of gestation followed by hormone replacement therapy. Nara and coworkers demonstrated that in pigs ovariectomized in late pregnancy a prolonged delivery and a low incidence of live births occurred in the absence of relaxin replacement. Eldridge-White and coworkers demonstrated that in intact pregnant pigs beginning about day 80 of pregnancy and continuing until term, cervical extensibility and size increased coinciding with rising relaxin and estrogen levels.","In the first study I explored the hypothesis that the deleterious effects on birth seen in the absence of relaxin were, at least partially, attributable to a failure of the cervix to grow and soften. This study demonstrated that in ovariectomized pregnant pigs increases in extensibility and growth of the cervix occurred only in the presence of relaxin. The second study demonstrated that the growth and softening of the cervix promoted by relaxin in ovariectomized pregnant pigs is accompanied by a decrease in collagen concentration and increases in water content, dry weight, and the glycosaminoglycan:collagen ratio. These results support the hypothesis that relaxin-induced changes in cervical connective tissue components may account, in part, for relaxin's effects on cervical extensibility, cervical growth and normal birth in pigs.","The third study examined relaxin's influence on mammary gland development. In ovariectomized pregnant pigs, growth of the mammary parenchymal tissue during the last third of gestation occurred only with relaxin administration. These results suggest that relaxin' s stimulation of mammogenesis may be important for normal lactation in pigs.","In conclusion, this research demonstrates two important physiological roles for relaxin during pregnancy in pigs. Relaxin promotes increased cervical extensibility and growth, as well as, mammary gland development.","Made available in DSpace on 2011-05-07T14:08:46Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9136549.pdf: 5662857 bytes, checksum: 94b6b3c5e4cda62f612d8dc8e5a0f0f3 (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:03:27Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:30:14-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"],"dc:identifier":["AAI9136549","(UMI)AAI9136549","http://hdl.handle.net/2142/23286"],"dc:language":["eng"],"dc:rights":["Copyright 1991 Bowman, Mary Bridget"],"dc:subject":["Biology, Animal Physiology"],"dc:title":["The physiological role of relaxin in the pregnant gilt: The effects of relaxin on the physical and biochemical properties of the cervix and on mammary development in ovariectomized hormone-treated pregnant gilts"],"dc:type":["text"],"thesis:degree_discipline":["Molecular and Integrative Physiology"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:21Z"}