{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/80240"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/80240","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Influence of energy level during gestation on the postpartum endocrine system in the mare","abstract":"Eight pregnant mares were randomly allotted to receive 100 and 120% of the recommended digestible energy (DE) (NRC, 1978), respectively, for the last 90 d of gestation. During the first 30 d of lactation, all mares were fed the NRC (1978) recommendations for lactation. The 120% DE-fed mares had an advantage of .18 kg (P<. 03) ADG during the last 90 d of gestation. The length of gestation and foal birth weight were unaffected by treatment. During 30 d postpartum, 120% DE-fed mares lost .16 kg/d while 100% DE-fed mares gained .33 kg/d (P<.04). Postpartum mare ADG were supported by foal ADG, with foals on 120% DE-fed mares having gained .37 kg/d more (P<.06) than 100% DE foals. Pooled data for all mares showed that day to first postpartum ovulation and follicle size on the eighth day postpartum were negatively (r=-.80; P<.05) correlated. First estrus postpartum was negatively correlated (r=-.69; P<.01) to follicle size at the eighth day postpartum and was positively correlated (r=.91; P<.01) to the day of first postpartum ovulation. Serum progesterone (P₄) and luteinizing hormone (LH) values were obtained at 3 d intervals starting 3 wk prepartum through 30 d postpartum with daily values 1 wk pre- and postpartum. No treatment differences within period in hormone concentrations were seen. However, the curvilinear effects of day for LH concentration up to and including the fifth order (r²=.73) and the seventh order for P₄ concentrations (r²=.59) were highly significant (P<.01). All mares received 100 µg gonadotropin releasing hormone (GnRH) on d 6 postpartum. Seven of 8 mares exhibited an LH response (P<.01) within 6 h post-administration. The 120% DE-fed mares experienced an advantage of weight gain during gestation and their foals gained faster during 30 d postpartum. No treatment differences were found for pre- and postpartum hormone concentrations or for the responsiveness of the pituitary as determined by GnRH administration.","abstract_html":"Eight pregnant mares were randomly allotted to receive 100 and 120% of the recommended digestible energy (DE) (NRC, 1978), respectively, for the last 90 d of gestation. During the first 30 d of lactation, all mares were fed the NRC (1978) recommendations for lactation. The 120% DE-fed mares had an advantage of .18 kg (P&lt;. 03) ADG during the last 90 d of gestation. The length of gestation and foal birth weight were unaffected by treatment. During 30 d postpartum, 120% DE-fed mares lost .16 kg/d while 100% DE-fed mares gained .33 kg/d (P&lt;.04). Postpartum mare ADG were supported by foal ADG, with foals on 120% DE-fed mares having gained .37 kg/d more (P&lt;.06) than 100% DE foals. Pooled data for all mares showed that day to first postpartum ovulation and follicle size on the eighth day postpartum were negatively (r=-.80; P&lt;.05) correlated. First estrus postpartum was negatively correlated (r=-.69; P&lt;.01) to follicle size at the eighth day postpartum and was positively correlated (r=.91; P&lt;.01) to the day of first postpartum ovulation. Serum progesterone (P₄) and luteinizing hormone (LH) values were obtained at 3 d intervals starting 3 wk prepartum through 30 d postpartum with daily values 1 wk pre- and postpartum. No treatment differences within period in hormone concentrations were seen. However, the curvilinear effects of day for LH concentration up to and including the fifth order (r²=.73) and the seventh order for P₄ concentrations (r²=.59) were highly significant (P&lt;.01). All mares received 100 µg gonadotropin releasing hormone (GnRH) on d 6 postpartum. Seven of 8 mares exhibited an LH response (P&lt;.01) within 6 h post-administration. The 120% DE-fed mares experienced an advantage of weight gain during gestation and their foals gained faster during 30 d postpartum. No treatment differences were found for pre- and postpartum hormone concentrations or for the responsiveness of the pituitary as determined by GnRH administration.","abstract_has_math":false,"creators":["Fennell, Michael Joseph"],"institution":"Virginia Polytechnic Institute and State University","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Animal Science (Reproductive Physiology)","degree_department":"Animal Science (Reproductive Physiology)","school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1982,"date_issued":"1982","date_published":"1982","updated_at":"2026-07-22T22:20:37Z","subjects":[],"languages":["en_US"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10919/80240","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.department","label":"Department","values":["Animal Science (Reproductive Physiology)"]},{"key":"dc:creator","label":"Author","values":["Fennell, Michael Joseph"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2017-11-09T21:31:59Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2017-11-09T21:31:59Z"]},{"key":"dc:date.issued","label":"Date","values":["1982"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Polytechnic Institute and State University"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.dcmitype","label":"Dc Type Dcmitype","values":["Text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Animal Science (Reproductive Physiology)"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]},{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/80240"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Eight pregnant mares were randomly allotted to receive 100 and 120% of the recommended digestible energy (DE) (NRC, 1978), respectively, for the last 90 d of gestation. During the first 30 d of lactation, all mares were fed the NRC (1978) recommendations for lactation. The 120% DE-fed mares had an advantage of .18 kg (P<. 03) ADG during the last 90 d of gestation. The length of gestation and foal birth weight were unaffected by treatment. During 30 d postpartum, 120% DE-fed mares lost .16 kg/d while 100% DE-fed mares gained .33 kg/d (P<.04). Postpartum mare ADG were supported by foal ADG, with foals on 120% DE-fed mares having gained .37 kg/d more (P<.06) than 100% DE foals. Pooled data for all mares showed that day to first postpartum ovulation and follicle size on the eighth day postpartum were negatively (r=-.80; P<.05) correlated. First estrus postpartum was negatively correlated (r=-.69; P<.01) to follicle size at the eighth day postpartum and was positively correlated (r=.91; P<.01) to the day of first postpartum ovulation. Serum progesterone (P₄) and luteinizing hormone (LH) values were obtained at 3 d intervals starting 3 wk prepartum through 30 d postpartum with daily values 1 wk pre- and postpartum. No treatment differences within period in hormone concentrations were seen. However, the curvilinear effects of day for LH concentration up to and including the fifth order (r²=.73) and the seventh order for P₄ concentrations (r²=.59) were highly significant (P<.01). All mares received 100 µg gonadotropin releasing hormone (GnRH) on d 6 postpartum. Seven of 8 mares exhibited an LH response (P<.01) within 6 h post-administration. The 120% DE-fed mares experienced an advantage of weight gain during gestation and their foals gained faster during 30 d postpartum. No treatment differences were found for pre- and postpartum hormone concentrations or for the responsiveness of the pituitary as determined by GnRH administration."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Influence of energy level during gestation on the postpartum endocrine system in the mare"]}]}],"canonical_facts":{"dc:contributor.department":["Animal Science (Reproductive Physiology)"],"dc:creator":["Fennell, Michael Joseph"],"dc:date.accessioned":["2017-11-09T21:31:59Z"],"dc:date.available":["2017-11-09T21:31:59Z"],"dc:date.issued":["1982"],"dc:description.abstract":["Eight pregnant mares were randomly allotted to receive 100 and 120% of the recommended digestible energy (DE) (NRC, 1978), respectively, for the last 90 d of gestation. During the first 30 d of lactation, all mares were fed the NRC (1978) recommendations for lactation. The 120% DE-fed mares had an advantage of .18 kg (P<. 03) ADG during the last 90 d of gestation. The length of gestation and foal birth weight were unaffected by treatment. During 30 d postpartum, 120% DE-fed mares lost .16 kg/d while 100% DE-fed mares gained .33 kg/d (P<.04). Postpartum mare ADG were supported by foal ADG, with foals on 120% DE-fed mares having gained .37 kg/d more (P<.06) than 100% DE foals. Pooled data for all mares showed that day to first postpartum ovulation and follicle size on the eighth day postpartum were negatively (r=-.80; P<.05) correlated. First estrus postpartum was negatively correlated (r=-.69; P<.01) to follicle size at the eighth day postpartum and was positively correlated (r=.91; P<.01) to the day of first postpartum ovulation. Serum progesterone (P₄) and luteinizing hormone (LH) values were obtained at 3 d intervals starting 3 wk prepartum through 30 d postpartum with daily values 1 wk pre- and postpartum. No treatment differences within period in hormone concentrations were seen. However, the curvilinear effects of day for LH concentration up to and including the fifth order (r²=.73) and the seventh order for P₄ concentrations (r²=.59) were highly significant (P<.01). All mares received 100 µg gonadotropin releasing hormone (GnRH) on d 6 postpartum. Seven of 8 mares exhibited an LH response (P<.01) within 6 h post-administration. The 120% DE-fed mares experienced an advantage of weight gain during gestation and their foals gained faster during 30 d postpartum. No treatment differences were found for pre- and postpartum hormone concentrations or for the responsiveness of the pituitary as determined by GnRH administration."],"dc:description.degree":["Master of Science"],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["http://hdl.handle.net/10919/80240"],"dc:language.iso":["en_US"],"dc:publisher":["Virginia Polytechnic Institute and State University"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:title":["Influence of energy level during gestation on the postpartum endocrine system in the mare"],"dc:type":["Thesis"],"dc:type.dcmitype":["Text"],"thesis:degree_discipline":["Animal Science (Reproductive Physiology)"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:20:37Z"}