Show simple item record

dc.contributor.authorRandi, Federico
dc.contributor.authorSánchez, José Maria
dc.contributor.authorHerlihy, Mary M.
dc.contributor.authorValenza, Alessio
dc.contributor.authorKenny, David A.
dc.contributor.authorButler, Stephen
dc.contributor.authorLonergan, P.
dc.date.accessioned2019-08-14T13:51:30Z
dc.date.available2019-08-14T13:51:30Z
dc.date.issued2018-08-23
dc.identifier.citationRandi, F., Sánchez, J., Herlihy, M., Valenza, A., Kenny, D., Butler, S. and Lonergan, P. (2018). Effect of equine chorionic gonadotropin treatment during a progesterone-based timed artificial insemination program on reproductive performance in seasonal-calving lactating dairy cows. Journal of Dairy Science, [online] 101(11), pp.10526-10535. Available at: https://dx.doi.org/10.3168/jds.2018-14495.en_US
dc.identifier.urihttp://hdl.handle.net/11019/1743
dc.descriptionpeer-revieweden_US
dc.description.abstractThe aim of this study was to investigate the effect of progesterone (P4)-based timed artificial insemination (TAI) programs on fertility in seasonal-calving, pasture-based dairy herds. A total of 1,421 lactating dairy cows on 4 spring-calving farms were stratified based on days in milk (DIM) and parity and randomly allocated to 1 of 3 treatments: (1) control: no hormonal treatment; cows inseminated at detected estrus; (2) P4-Ovsynch: cows received a 7-d P4-releasing intravaginal device (PRID Delta; CEVA Santé Animale, Libourne, France) with 100 μg of a gonadotropin-releasing hormone (GnRH) analog (Ovarelin; CEVA Santé Animale) at PRID insertion, a 25-mg injection of PGF2α (Enzaprost; CEVA Santé Animale) at PRID removal, GnRH at 56 h after device removal and TAI 16 h later; (3) P4-Ovsynch+eCG: the same as P4-Ovsynch, but cows received 500 IU of equine chorionic gonadotropin (eCG; Syncrostim; CEVA Santé Animale) at PRID removal. At 10 d before mating start date (MSD), all cows that were ≥35 DIM were examined by transrectal ultrasound to assess presence or absence of a corpus luteum; body condition score (BCS) was also recorded. Pregnancy diagnosis was performed by transrectal ultrasonography 30 to 35 d after insemination. Overall pregnancy/AI (P/AI) was not different between groups (50.9, 49.8, and 46.3% for control, P4-Ovsynch, and P4-Ovsynch+eCG, respectively) but the 21-d pregnancy rate was increased by the use of synchronization (35.0, 51.7, and 47.2%, respectively). Compared with the control group, synchronization significantly reduced the interval from MSD to conception (34.6, 23.0, and 26.5 d, respectively) and consequently reduced the average days open (98.0, 86.0, and 89.0 d). Across all treatment groups, DIM at the start of synchronization affected P/AI (42.3, 49.5, and 53.9% for <60, 60–80, and >80 DIM, respectively), but neither parity (46.5, 50.4, and 48.4% for parity 1, 2, and ≥3, respectively) nor BCS (44.0, 49.4, and 58.6% for ≤2.50, 2.75–3.25, and ≥3.50, respectively) affected the likelihood of P/AI. Two-way interactions between treatment and DIM, parity, or BCS were not detected. In conclusion, the use of TAI accelerated pregnancy establishment in cows in a pasture-based system by reducing days open, but eCG administration at PRID removal did not affect P/AI.en_US
dc.language.isoenen_US
dc.publisherElsevieren_US
dc.relation.ispartofseriesJournal of Dairy Science;Vol. 101 (11)
dc.rightsAttribution-NonCommercial-ShareAlike 3.0 United States*
dc.rights.urihttp://creativecommons.org/licenses/by-nc-sa/3.0/us/*
dc.subjecttimed artificial inseminationen_US
dc.subjectpasture-based dairy productionen_US
dc.subjectequine chorionic gonadotropinen_US
dc.subjectsubmission rateen_US
dc.subjectpregnancy/AIen_US
dc.titleEffect of equine chorionic gonadotropin treatment during a progesterone-based timed artificial insemination program on reproductive performance in seasonal-calving lactating dairy cowsen_US
dc.typeArticleen_US
dc.embargo.terms2019-08-23en_US
dc.identifier.doihttps://dx.doi.org/10.3168/jds.2018-14495
dc.contributor.sponsorDepartment of Agriculture, Food and the Marineen_US
dc.contributor.sponsorGrantNumber13S515en_US
dc.contributor.sponsorGrantNumber13S528en_US


Files in this item

Thumbnail
Name:
1-s2.0-S0022030218307604-main.pdf
Size:
466.5Kb
Format:
PDF
Description:
main article

This item appears in the following Collection(s)

Show simple item record

Attribution-NonCommercial-ShareAlike 3.0 United States
Except where otherwise noted, this item's license is described as Attribution-NonCommercial-ShareAlike 3.0 United States