Synchronization of Estrus in Beef Cattle with PGF2 α and Estradiol Benzoate
- 31 July 1977
- journal article
- research article
- Published by Oxford University Press (OUP) in Journal of Animal Science
- Vol. 45 (2) , 230-235
- https://doi.org/10.2527/jas1977.452230x
Abstract
Five trials were conducted to compare the efficacy of one or two intramuscular injections of PGF2 α, with or without subsequent treatment with estradiol benzoate, for synchronization of estrus in beef cows and heifers with palpable corpora lutea. Intramuscular injection of 400 µg estradiol benzoate 48 hr after PGF2α increased the precision of synchronization of estrus in both lactating beef cows and heifers (P<.05). Onset of estrus within a target period 56 to 86 hr after PGF2 α was increased by 23 and 15 percentage points, in the cows and heifers respectively, by the estrogen treatment. Response was not altered when estradiol benzoate was given 40 vs 48 hr after PGF2 α. Conception and pregnancy rates were not altered by estradiol benzoate. A second injection of PGF2 α 12 days after the first gave no advantage in synchronization of estrus in animals with palpable corpora lutea at the time of the first injection. Copyright © 1977. American Society of Animal Science . Copyright 1977 by American Society of Animal Science.This publication has 0 references indexed in Scilit: