Incidence and treatment of inadequate postovulatory progesterone concentrations in repeat breeder cows.
The incidence of low day 5 milk progesterone in dairy cows has been investigated and the efficacy of treating the problem assessed. The incidence of inadequate milk progesterone (empirically defined as <3ng/mL) in repeat breeder cows was 34% compared with 11.4% in first insemination cows. Treatment with an intravaginal progesterone device for 7 days starting from day 5 or 6 did not improve pregnancy rate. Treatment with 1500 iu human chorionic gonadotrophin (hCG) on day 5 gave an increase in pregnancy rate that was dependent on initial progesterone concentration and significant (P<0.05) in multiparous but not primiparous cows. While the incidence of inadequate day 5 progesterone was high in repeat breeder cows, it was responsive to hCG treatment, although only in multiparous and not primiparous animals.
Kendall
N R
NR
School of Veterinary Medicine and Science University of Nottingham, Sutton Bonington Campus, Loughborough LEI2 5RD, UK.
Flint
A P F
AP
Mann
G E
GE
D000818:Animals; D001947:Breeding; D002417:Cattle; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D003612:Dairying; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D008892:Milk / Q000737:chemistry* / Q000187:drug effects; D010060:Ovulation / Q000502:physiology*; D010298:Parity; D011247:Pregnancy; D011374:Progesterone / Q000032:analysis* / Q000172:deficiency / Q000378:metabolism
D006063:Chorionic Gonadotropin; D011374:Progesterone