Five-day resynch programs in dairy cows including controlled internal drug release at two stages post-artificial insemination

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dc.contributor.author Pulley, Stephanie Leeann
dc.contributor.author Hill, Scott L.
dc.contributor.author Stevenson, Jeffrey S.
dc.date.accessioned 2014-03-26T18:01:43Z
dc.date.available 2014-03-26T18:01:43Z
dc.date.issued 2014-03-26
dc.identifier.uri http://hdl.handle.net/2097/17269
dc.description Dairy Research, 2013 is known as Dairy Day, 2013 en_US
dc.description.abstract Two experiments were conducted to assess pregnancy outcomes after a 5-day Ovsynch-56 Resynch (RES; gonadotropin-releasing hormone injection 5 days before [GnRH-1; d 0] and 56 hours (GnRH-2) after PGF2α [PG] injections on day 5 and 6, timed artificial insemination [TAI] on day 8) with and without a progesterone-releasing intravaginal controlled internal drug release (CIDR) 5-day insert. In Exp. 1, nonpregnant cows were enrolled on day 34 post- AI: day 34 RES-CON (n = 528) or day 34 RES-CIDR (n = 503). Blood was collected for progesterone assay. Pregnancy per AI (P/AI) was diagnosed by uterine palpation per rectum at 34 and 62 days post-TAI. Only 76% of 1,031 cows had high progesterone (≥1 ng/mL) on day 34 at the nonpregnant diagnosis. No differences in P/AI were detected between treatments. The day-34 RES-CIDR cows with low (<1 ng/mL) progesterone, however, had greater (P = 0.036) P/AI than day-34 RES-CON cows (37.7 vs. 29.4%), whereas day-34 RES-CIDR cows with high progesterone had lesser P/AI than day-34 RES-CON (27.4 vs. 34.3%). In Exp. 2, cows were enrolled on day 31 post-AI after a nonpregnant diagnosis: (1) day 31 PG-3-G (n = 102): Pre-PG on day 31, Pre-GnRH on day 34, and RES on day 41 (n = 102); (2) day 41 RES-CON (n = 108) as Exp. 1, but on day 41; and (3) day 41 RES-CIDR (n = 101) as Exp. 2, but on day 41. Blood was collected for progesterone assay and ovarian structures were mapped by ultrasonography on days 31, 34, 41, 46, and 48. Pregnancy was diagnosed by ultrasonography on days 31 and 59 post-TAI. The proportion of cows with high progesterone on day 31 was 70.6%. More (P < 0.001) cows ovulated after Pre-GnRH on day 31 PG-3-G (60.4%) than for day 41 RES-CON (12.5%) or day 41 RES-CIDR (17.1%). More (P < 0.001) PG-3-G cows had luteolysis after Pre-PG on day 31 than other treatments (73.7 vs. < 11%). The proportion of cows with high progesterone on day 41 at GnRH-1 tended (P = 0.10) to be greater for PG-3-G (75.6%) than for other treatments (65 to 70%). The P/AI was greater in cows starting RES on day 41 when progesterone was low (44%) than when it was high (33%), but no treatment differences were detected 31 days after TAI (PG-3-G = 33.3%; d 41 RES-CON = 38.9%; d 41 RES-CIDR = 35.6%). We concluded that improved P/AI for cows initiating the 5-day RES on day 34 without a corpus luteum is progesterone-dependent because addition of the CIDR insert to the RES treatment improved P/AI in cows with low progesterone (Exp. 1). Although day-31 PG-3-G increased luteolysis and produced greater ovulation rates before the onset of RES, no increase in P/AI was detected compared with RES started on day 41 with or without a CIDR insert. en_US
dc.language.iso en_US en_US
dc.publisher Kansas Agricultural Experiment Station and Cooperative Extension Service en_US
dc.relation.isPartOf Dairy Day, 2013 en_US
dc.relation.isPartOf Kansas Agricultural Experiment Station contribution; no. 14-179-S en_US
dc.relation.isPartOf Report of progress (Kansas Agricultural Experiment Station and Cooperative Extension Service);1093 en_US
dc.subject CIDR en_US
dc.subject Resynch en_US
dc.subject Pregnancy en_US
dc.title Five-day resynch programs in dairy cows including controlled internal drug release at two stages post-artificial insemination en_US
dc.type Conference paper en_US
dc.date.published 2013 en_US
dc.description.conference Dairy Day, 2013, Kansas State University, Manhattan, KS, 2013
dc.contributor.authoreid spulley en_US
dc.contributor.authoreid scotth22 en_US
dc.contributor.authoreid jss en_US


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