title: Progesterone supplementation during the time of pregnancy recognition after artificial insemination improves conception rates in high-producing dairy cows.
abstract: This study examines the possible effects of progesterone (P4) supplementation during the time of pregnancy recognition, from Days 15 to 17 post-artificial insemination (AI), on reproductive performance in high-producing dairy cows. Cows in their 15th day post-AI were alternately assigned to a control, no-treatment group (C: n = 257) or treatment group (P4: n = 287) on a weekly rotational basis according to the chronologic order of their gynecologic visit. On the basis of the odds ratio, the interaction treatment × previous placenta retention had a significant effect (P = 0.02) on conception rate. Thus, cows in P4 that had not suffered a retained placenta were 1.6 times more likely to conceive 28 to 34 days post-AI than the remaining cows. In nonpregnant cows, treatment had no effect on subsequent return to estrus or AI interval and neither were any effects of treatment observed on twin pregnancy and early fetal loss rates. The results of this study demonstrate the efficacy of P4 supplementations during the time of pregnancy recognition after AI in cows without a clinical history of placenta retention.
authors.affiliation: Department of Animal Production, Agotecnio Centre, University of Lleida, Lleida, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Garcia-Ispierto
authors.affiliation: Department of Animal Production, Agotecnio Centre, University of Lleida, Lleida, Spain.
authors.forename: I
authors.initials: I
authors.lastname: López-Helguera
authors.affiliation: Department of Animal Production, Agotecnio Centre, University of Lleida, Lleida, Spain.
authors.forename: B
authors.initials: B
authors.lastname: Serrano-Pérez
authors.affiliation: Department of Animal Production, Agotecnio Centre, University of Lleida, Lleida, Spain.
authors.forename: V
authors.initials: V
authors.lastname: Paso
authors.affiliation: Department of Animal Production, Agotecnio Centre, University of Lleida, Lleida, Spain.
authors.forename: T
authors.initials: T
authors.lastname: Tuono
authors.affiliation: Department of Animal Production, Agotecnio Centre, University of Lleida, Lleida, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Ramon
authors.affiliation: Department of Animal Production, Agotecnio Centre, University of Lleida, Lleida, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Mur-Novales
authors.affiliation: Department of Animal Production, Agotecnio Centre, University of Lleida, Lleida, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Tutusaus
authors.affiliation: Department of Animal Production, Agotecnio Centre, University of Lleida, Lleida, Spain. Electronic address: flopez@prodan.udl.cat.
authors.forename: F
authors.initials: F
authors.lastname: López-Gatius
mesh_terms: D000818:Animals; D002417:Cattle / Q000502:physiology*; D005260:Female; D005306:Fertilization / Q000187:drug effects*; D007315:Insemination, Artificial / Q000662:veterinary*; D016017:Odds Ratio; D011247:Pregnancy; D011374:Progesterone / Q000008:administration & dosage / Q000494:pharmacology*; D011372:Progestins / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D011372:Progestins; D011374:Progesterone
keywords: Bovine; Fertility; Preimplantation period