dc.contributor | Univ Florida | |
dc.contributor | Universidade Estadual Paulista (Unesp) | |
dc.contributor | Univ Estado Santa Catarina | |
dc.date.accessioned | 2014-12-03T13:08:56Z | |
dc.date.available | 2014-12-03T13:08:56Z | |
dc.date.created | 2014-12-03T13:08:56Z | |
dc.date.issued | 2014-06-01 | |
dc.identifier | Journal Of Dairy Science. New York: Elsevier Science Inc, v. 97, n. 6, p. 3558-3569, 2014. | |
dc.identifier | 0022-0302 | |
dc.identifier | http://hdl.handle.net/11449/111742 | |
dc.identifier | 10.3168/jds.2013-7533 | |
dc.identifier | WOS:000336192100031 | |
dc.description.abstract | The objective of the current study was to evaluate the effect of GnRH early postpartum on induction of ovulation, uterine health, and fertility in dairy cows. Holstein cows without a corpus luteum (CL) at 17 +/- 3 DIM were assigned randomly to receive i.m. GnRH (n = 245) at 17 +/- 3 and 20 +/- 3 DIM or remain as controls (n = 245). Ovaries were scanned by ultrasonography twice weekly totaling 4 examinations. Ovulation was characterized by the appearance of a CL >= 20 mm at any ultrasound or CL <20 mm in 2 consecutive examinations. Clinical and cytological endometritis were diagnosed at 35 DIM. Compared with control, GnRH increased ovulation up to 3.5 d after the last treatment (78.7 vs. 45.0%) and did not affect the prevalence of clinical endometritis (23.9 vs. 18.6%) or cytological endometritis (30.9 vs. 32.8%). Prevalence of clinical endometritis increased in cows that had calving problems (32.6 vs. 15.9%) and metritis (40.6 vs. 15.8%). Metritis increased prevalence of cytological endometritis (50.7 vs. 23.5%). Treatment with GnRH did not affect pregnancy per artificial insemination at 32 (37.6 vs. 38.6%) or 74 d after artificial insemination (35.0 vs. 31.5%), but reduced pregnancy loss (6.8 vs. 18.1%). No overall effect of GnRH treatment on hazard of pregnancy was observed; however, an interaction between GnRH treatment and ovulation showed that GnRH-treated cows that ovulated had increased hazard of pregnancy by 300 DIM compared with GnRH-treated and control cows that did not ovulate (hazard ratio = 2.0 and 1.3, respectively), but similar to control cows that ovulated (hazard ratio = 1.1). Gonadotropin-releasing hormone early postpartiim induced ovulation without affecting uterine health, but failed to improve pregnancy per artificial insemination or time to pregnancy, although it reduced pregnancy loss. | |
dc.language | eng | |
dc.publisher | Elsevier B.V. | |
dc.relation | Journal of Dairy Science | |
dc.relation | 2.749 | |
dc.relation | 1,350 | |
dc.rights | Acesso restrito | |
dc.source | Web of Science | |
dc.subject | dairy cow | |
dc.subject | ovulation postpartum | |
dc.subject | GnRH | |
dc.subject | uterine health | |
dc.subject | fertility | |
dc.title | Inducing ovulation early postpartum influences uterine health and fertility in dairy cows | |
dc.type | Artículos de revistas | |