title: Evaluation of different protocols for prostaglandin synchronization to improve reproductive performance in dairy herds with low estrus detection efficiency.
abstract: The objective of this study was to evaluate different PGF2 alpha protocols against control protocols for herds with estrus detection efficiencies of 35, 55, and 75% using modeling and simulation: 1) PGF2 alpha treatments based on the presence of a corpus luteum diagnosed by rectal palpation, 2) PGF2 alpha treatments based on the presence of a corpus luteum diagnosed by an on-farm milk progesterone enzyme immunoassay, and 3) PGF2 alpha treatments based on a 14-d fixed treatment schedule without prior screening for ovarian status. After the start of each protocol, estrus detection efficiency was 75% for 7 d after treatment and 35 or 0% for the following week. For the third protocol, an additional modification at estrus detection efficiencies of 85 and 55%, respectively, in the 1st and 2nd wk after treatment was evaluated to establish a protocol for best case assumptions. All protocols improved reproductive performance relative to that of controls with estrus detection efficiencies of 35 and 55%. The mean number of days open was reduced from 124.3 d in the control herd to 95.9, 95.0, and 92.7 for the protocols based on rectal palpation, milk progesterone test, and the fixed treatment schedule, respectively. The protocols based on a fixed treatment schedule were superior to protocols based on rectal palpation and on-farm milk progesterone tests and resulted in better reproductive performance and a higher increase in net return per cow per year. Relative to a control herd with an estrus detection efficiency of 55%, it was cost effective to spend up to $10 per dose of PGF2 alpha, $9 per milk progesterone test, and $6 per rectal palpation.
authors.affiliation: Clinic of Reproduction, Free University of Berlin, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Heuwieser
authors.forename: P A
authors.initials: PA
authors.lastname: Oltenacu
authors.forename: A J
authors.initials: AJ
authors.lastname: Lednor
authors.forename: R H
authors.initials: RH
authors.lastname: Foote
mesh_terms: D000818:Animals; D002417:Cattle / Q000502:physiology*; D003338:Corpus Luteum; D003362:Cost-Benefit Analysis; D015237:Dinoprost / Q000008:administration & dosage*; D004972:Estrus Detection / Q000191:economics; D004973:Estrus Synchronization; D005260:Female; D008892:Milk / Q000737:chemistry; D010173:Palpation; D011247:Pregnancy; D011374:Progesterone / Q000032:analysis; D012007:Rectum; D012098:Reproduction
chemical_list: D011374:Progesterone; D015237:Dinoprost