{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/19637"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/19637","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Postweaning anestrus in the sows: Effect of the low-energy diet during lactation","abstract":"Low energy (LE) intake during lactation results in a delay in the onset of estrus following weaning in primiparous sows. Our first goal was to determine whether LE intake during lactation causes a postweaning imbalance in reproductive and metabolic hormones. Effects of a decreased level of dietary energy intake during lactation on plasma concentrations of estradiol (E$\\sb2$), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), growth hormone (GH), thyroxine (T4), triiodothyronine (T3), progesterone (P$\\sb4$), cortisol, urea, and glucose were investigated in 16 primiparous crossbred sows. Mean daily concentrations of plasma FSH, E$\\sb2$ and LH were lower in LE sows than control (CO) fed sows. Thyroxine concentration was higher in the anestrous sows than the estrous sows during anestrus period. The postweaning high concentrations of T4 in plasma of the LE sows may be one of the factors that mediates the effect of LE diet during lactation on subsequent estrous cycle. The other goal was to determine whether inhibition of gonadotropin releasing hormone (GnRH) and/or LE secretion is the cause for the lower plasma LH concentrations in postweaning anestrous sows. Results suggest that the postweaning decrease of LH secretion caused by LE intake during 28 days of lactation may be mediated through inactivation of the NMA receptors and an increase in the sensitivity of the hypothalamic-pituitary axis to the negative feedback effect of E$\\sb2$. The mechanism by which LE diet causes an extended postweaning anestrus may be through an increase in the number of NMA receptors and sensitivity of the hypothalamic-pituitary to negative feedback effect of E$\\sb2$ to decrease LH secretion in postweaning anestrous sows. An increase in TRH release as suggested indirectly by the presence of high concentration of plasma T4, may inhibit GnRH release and LH secretion. This suggested mechanism may be a system through which LE diet causes postweaning anestrus in the sow. (Abstract shortened with permission of author.)","abstract_html":"Low energy (LE) intake during lactation results in a delay in the onset of estrus following weaning in primiparous sows. Our first goal was to determine whether LE intake during lactation causes a postweaning imbalance in reproductive and metabolic hormones. Effects of a decreased level of dietary energy intake during lactation on plasma concentrations of estradiol (E$\\sb2$), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), growth hormone (GH), thyroxine (T4), triiodothyronine (T3), progesterone (P$\\sb4$), cortisol, urea, and glucose were investigated in 16 primiparous crossbred sows. Mean daily concentrations of plasma FSH, E$\\sb2$ and LH were lower in LE sows than control (CO) fed sows. Thyroxine concentration was higher in the anestrous sows than the estrous sows during anestrus period. The postweaning high concentrations of T4 in plasma of the LE sows may be one of the factors that mediates the effect of LE diet during lactation on subsequent estrous cycle. The other goal was to determine whether inhibition of gonadotropin releasing hormone (GnRH) and/or LE secretion is the cause for the lower plasma LH concentrations in postweaning anestrous sows. Results suggest that the postweaning decrease of LH secretion caused by LE intake during 28 days of lactation may be mediated through inactivation of the NMA receptors and an increase in the sensitivity of the hypothalamic-pituitary axis to the negative feedback effect of E$\\sb2$. The mechanism by which LE diet causes an extended postweaning anestrus may be through an increase in the number of NMA receptors and sensitivity of the hypothalamic-pituitary to negative feedback effect of E$\\sb2$ to decrease LH secretion in postweaning anestrous sows. An increase in TRH release as suggested indirectly by the presence of high concentration of plasma T4, may inhibit GnRH release and LH secretion. This suggested mechanism may be a system through which LE diet causes postweaning anestrus in the sow. (Abstract shortened with permission of author.)","abstract_has_math":true,"creators":["Khazali, Homayoun"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Animal Sciences","degree_department":null,"school":null,"contributors":["Bahr, Janice M."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T12:13:46Z","date_published":"2011-05-07T12:13:46Z","updated_at":"2026-07-22T22:25:14Z","subjects":["Biology, Neuroscience","Biology, Animal Physiology","Engineering, Biomedical"],"languages":["eng"],"rights":["Copyright 1992 Khazali, Homayoun"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9236499","(UMI)AAI9236499"],"render_values":[{"text":"AAI9236499","href":null,"code":true},{"text":"(UMI)AAI9236499","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/19637","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Bahr, Janice M."]},{"key":"dc:creator","label":"Author","values":["Khazali, Homayoun"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T12:13:46Z","10000-01-01","1992"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Animal Sciences"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Biology, Neuroscience","Biology, Animal Physiology","Engineering, Biomedical"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 1992 Khazali, Homayoun"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9236499","(UMI)AAI9236499","http://hdl.handle.net/2142/19637"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Low energy (LE) intake during lactation results in a delay in the onset of estrus following weaning in primiparous sows. Our first goal was to determine whether LE intake during lactation causes a postweaning imbalance in reproductive and metabolic hormones. Effects of a decreased level of dietary energy intake during lactation on plasma concentrations of estradiol (E$\\sb2$), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), growth hormone (GH), thyroxine (T4), triiodothyronine (T3), progesterone (P$\\sb4$), cortisol, urea, and glucose were investigated in 16 primiparous crossbred sows. Mean daily concentrations of plasma FSH, E$\\sb2$ and LH were lower in LE sows than control (CO) fed sows. Thyroxine concentration was higher in the anestrous sows than the estrous sows during anestrus period. The postweaning high concentrations of T4 in plasma of the LE sows may be one of the factors that mediates the effect of LE diet during lactation on subsequent estrous cycle. The other goal was to determine whether inhibition of gonadotropin releasing hormone (GnRH) and/or LE secretion is the cause for the lower plasma LH concentrations in postweaning anestrous sows. Results suggest that the postweaning decrease of LH secretion caused by LE intake during 28 days of lactation may be mediated through inactivation of the NMA receptors and an increase in the sensitivity of the hypothalamic-pituitary axis to the negative feedback effect of E$\\sb2$. The mechanism by which LE diet causes an extended postweaning anestrus may be through an increase in the number of NMA receptors and sensitivity of the hypothalamic-pituitary to negative feedback effect of E$\\sb2$ to decrease LH secretion in postweaning anestrous sows. An increase in TRH release as suggested indirectly by the presence of high concentration of plasma T4, may inhibit GnRH release and LH secretion. This suggested mechanism may be a system through which LE diet causes postweaning anestrus in the sow. (Abstract shortened with permission of author.)","Made available in DSpace on 2011-05-07T12:13:46Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9236499.pdf: 3824171 bytes, checksum: 8acc497afb7ca8eb339084c0d0affeb8 (MD5) Previous issue date: 1992","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:38:24Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:16:01-05:00 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":["Postweaning anestrus in the sows: Effect of the low-energy diet during lactation"]}]}],"canonical_facts":{"dc:contributor":["Bahr, Janice M."],"dc:creator":["Khazali, Homayoun"],"dc:date":["2011-05-07T12:13:46Z","10000-01-01","1992"],"dc:description":["Low energy (LE) intake during lactation results in a delay in the onset of estrus following weaning in primiparous sows. Our first goal was to determine whether LE intake during lactation causes a postweaning imbalance in reproductive and metabolic hormones. Effects of a decreased level of dietary energy intake during lactation on plasma concentrations of estradiol (E$\\sb2$), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), growth hormone (GH), thyroxine (T4), triiodothyronine (T3), progesterone (P$\\sb4$), cortisol, urea, and glucose were investigated in 16 primiparous crossbred sows. Mean daily concentrations of plasma FSH, E$\\sb2$ and LH were lower in LE sows than control (CO) fed sows. Thyroxine concentration was higher in the anestrous sows than the estrous sows during anestrus period. The postweaning high concentrations of T4 in plasma of the LE sows may be one of the factors that mediates the effect of LE diet during lactation on subsequent estrous cycle. The other goal was to determine whether inhibition of gonadotropin releasing hormone (GnRH) and/or LE secretion is the cause for the lower plasma LH concentrations in postweaning anestrous sows. Results suggest that the postweaning decrease of LH secretion caused by LE intake during 28 days of lactation may be mediated through inactivation of the NMA receptors and an increase in the sensitivity of the hypothalamic-pituitary axis to the negative feedback effect of E$\\sb2$. The mechanism by which LE diet causes an extended postweaning anestrus may be through an increase in the number of NMA receptors and sensitivity of the hypothalamic-pituitary to negative feedback effect of E$\\sb2$ to decrease LH secretion in postweaning anestrous sows. An increase in TRH release as suggested indirectly by the presence of high concentration of plasma T4, may inhibit GnRH release and LH secretion. This suggested mechanism may be a system through which LE diet causes postweaning anestrus in the sow. (Abstract shortened with permission of author.)","Made available in DSpace on 2011-05-07T12:13:46Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9236499.pdf: 3824171 bytes, checksum: 8acc497afb7ca8eb339084c0d0affeb8 (MD5) Previous issue date: 1992","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:38:24Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:16:01-05:00 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":["AAI9236499","(UMI)AAI9236499","http://hdl.handle.net/2142/19637"],"dc:language":["eng"],"dc:rights":["Copyright 1992 Khazali, Homayoun"],"dc:subject":["Biology, Neuroscience","Biology, Animal Physiology","Engineering, Biomedical"],"dc:title":["Postweaning anestrus in the sows: Effect of the low-energy diet during lactation"],"dc:type":["text"],"thesis:degree_discipline":["Animal Sciences"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:14Z"}