{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/115787"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/115787","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Ovulatory response to GNRH agonist during early and late fall in mares","abstract":"Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2022-11-11 without embargo terms","abstract_html":"Submission original under an indefinite embargo labeled &#x27;Open Access&#x27;. The submission was exported from vireo on 2022-11-11 without embargo terms","abstract_has_math":false,"creators":["Spencer, Kianna M."],"institution":"University of Illinois at Urbana-Champaign","degree_name":"M.S.","degree_level":"Thesis","degree_discipline":"VMS-Veterinary Clinical Medcne","degree_department":null,"school":null,"contributors":["Canisso, Igor F","Marshall, Tessa S","Shipley, Clifford F","Garrett, Edgar F"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2022,"date_issued":"2022-05","date_published":"2022-05","updated_at":"2026-07-22T22:24:55Z","subjects":["ovulation","deslorelin acetate","progesterone","luteal function"],"languages":["en","eng"],"rights":["Copyright 2022 Kianna Spencer"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/2142/115787","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Canisso, Igor F","Marshall, Tessa S","Shipley, Clifford F","Garrett, Edgar F"]},{"key":"dc:creator","label":"Author","values":["Spencer, Kianna M."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2022-05","2022-04-29"]},{"key":"dc:type","label":"Dc Type","values":["text","Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["VMS-Veterinary Clinical Medcne"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.S."]},{"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":["ovulation","deslorelin acetate","progesterone","luteal function"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en","eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2022 Kianna Spencer"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://hdl.handle.net/2142/115787"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2022-11-11 without embargo terms","The student, Kianna Spencer, accepted the attached license on 2022-04-19 at 20:41.","The student, Kianna Spencer, submitted this Thesis for approval on 2022-04-27 at 12:04.","This Thesis was approved for publication on 2022-04-29 at 13:25.","DSpace SAF Submission Ingestion Package generated from Vireo submission #17824 on 2022-11-11 at 17:53:53","This study aimed to assess the ovulatory response of deslorelin acetate during the fall and the response to PGF2α 8 d post-ovulation. One hundred estrous cycles from 22 mares kept in 40o latitude were evaluated. Mares were checked by transrectal ultrasonography until a preovulatory follicle was detected and ovulation induced with deslorelin acetate. Ovulation was confirmed by ultrasonography performed at 24, 36 h post-induction and then repeated at 2-h intervals post-induction. Serum progesterone concentrations and luteal tissue area were determined daily to assess CL function. A dose of PGF2α was administered 8 d post-ovulation and interval to the subsequent ovulation was observed. Each mare repeated this cycle up to five times. The effects of local climate on endpoints were analyzed. Cycles were grouped as early (Sept. 13, 2020-Oct. 31, 2020; n=55) and late fall (Nov. 1, 2020- Dec. 31, 2020; n=45) based on the date of induction. The overall number of mare responding to deslorelin with ovulations between 24-48 h was 90%. Multiple ovulations were similar between early (n=5) and late (n=4) fall (P=0.87). There were no differences in spontaneous ovulations occurring before 24 h between early (n=6) and late (n=2) fall (P=0.29). Two failures to respond to deslorelin by 48 h were recorded in early fall and none in the late fall. The interval from induction to ovulation was similar in early (40.6±0.4 h) and late (41.2±0.5 h) fall (P=0.55). The percentage of mares ovulating between 36 and 48 h post-deslorelin did not vary between early and late fall (91 vs. 95 %, P=0.21), as did ovulation occurring between 38 h and 44 h (62 vs. 60%, P=0.69). Follicle size at induction tended to be smaller in early (36.4±0.4mm) than late (37.4±0.4mm) fall (P=0.07). Edema scores varied with time relative to ovulation (P<0.001) and were lower in late fall (P=0.01). Progesterone concentrations varied with time (P<0.001) but did not differ between early and late fall (P=0.73) and correlated weakly with the luteal area (r=0.13; P=0.031). Follicles < 35mm at the PGF2α had a shorter interval to the next ovulation than follicles ≥35mm (9.2±0.5 d vs. 10.6 ± 1.2 d) (P=0.03). Lower temperature led to a smaller follicle size at induction (P=0.0021) and ovulation (P=0.009) and lower relative humidity yielded a larger follicle size at ovulation (P=0.032). In conclusion, cycling mares displayed a highly efficacious response to deslorelin acetate and apparently normal luteal function during the fall, despite lower edema scores in late fall."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Ovulatory response to GNRH agonist during early and late fall in mares"]}]}],"canonical_facts":{"dc:contributor":["Canisso, Igor F","Marshall, Tessa S","Shipley, Clifford F","Garrett, Edgar F"],"dc:creator":["Spencer, Kianna M."],"dc:date":["2022-05","2022-04-29"],"dc:description":["Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2022-11-11 without embargo terms","The student, Kianna Spencer, accepted the attached license on 2022-04-19 at 20:41.","The student, Kianna Spencer, submitted this Thesis for approval on 2022-04-27 at 12:04.","This Thesis was approved for publication on 2022-04-29 at 13:25.","DSpace SAF Submission Ingestion Package generated from Vireo submission #17824 on 2022-11-11 at 17:53:53","This study aimed to assess the ovulatory response of deslorelin acetate during the fall and the response to PGF2α 8 d post-ovulation. One hundred estrous cycles from 22 mares kept in 40o latitude were evaluated. Mares were checked by transrectal ultrasonography until a preovulatory follicle was detected and ovulation induced with deslorelin acetate. Ovulation was confirmed by ultrasonography performed at 24, 36 h post-induction and then repeated at 2-h intervals post-induction. Serum progesterone concentrations and luteal tissue area were determined daily to assess CL function. A dose of PGF2α was administered 8 d post-ovulation and interval to the subsequent ovulation was observed. Each mare repeated this cycle up to five times. The effects of local climate on endpoints were analyzed. Cycles were grouped as early (Sept. 13, 2020-Oct. 31, 2020; n=55) and late fall (Nov. 1, 2020- Dec. 31, 2020; n=45) based on the date of induction. The overall number of mare responding to deslorelin with ovulations between 24-48 h was 90%. Multiple ovulations were similar between early (n=5) and late (n=4) fall (P=0.87). There were no differences in spontaneous ovulations occurring before 24 h between early (n=6) and late (n=2) fall (P=0.29). Two failures to respond to deslorelin by 48 h were recorded in early fall and none in the late fall. The interval from induction to ovulation was similar in early (40.6±0.4 h) and late (41.2±0.5 h) fall (P=0.55). The percentage of mares ovulating between 36 and 48 h post-deslorelin did not vary between early and late fall (91 vs. 95 %, P=0.21), as did ovulation occurring between 38 h and 44 h (62 vs. 60%, P=0.69). Follicle size at induction tended to be smaller in early (36.4±0.4mm) than late (37.4±0.4mm) fall (P=0.07). Edema scores varied with time relative to ovulation (P<0.001) and were lower in late fall (P=0.01). Progesterone concentrations varied with time (P<0.001) but did not differ between early and late fall (P=0.73) and correlated weakly with the luteal area (r=0.13; P=0.031). Follicles < 35mm at the PGF2α had a shorter interval to the next ovulation than follicles ≥35mm (9.2±0.5 d vs. 10.6 ± 1.2 d) (P=0.03). Lower temperature led to a smaller follicle size at induction (P=0.0021) and ovulation (P=0.009) and lower relative humidity yielded a larger follicle size at ovulation (P=0.032). In conclusion, cycling mares displayed a highly efficacious response to deslorelin acetate and apparently normal luteal function during the fall, despite lower edema scores in late fall."],"dc:format":["application/pdf"],"dc:identifier":["https://hdl.handle.net/2142/115787"],"dc:language":["en","eng"],"dc:rights":["Copyright 2022 Kianna Spencer"],"dc:subject":["ovulation","deslorelin acetate","progesterone","luteal function"],"dc:title":["Ovulatory response to GNRH agonist during early and late fall in mares"],"dc:type":["text","Thesis"],"thesis:degree_discipline":["VMS-Veterinary Clinical Medcne"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["M.S."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:24:55Z"}