Incidence and treatment of inadequate postovulatory progesterone concentrations in repeat breeder cows.

School of Veterinary Medicine and Science University of Nottingham, Sutton Bonington Campus, Loughborough LEI2 5RD, UK.
The Veterinary Journal (Impact Factor: 2.42). 07/2008; 181(2):158-62. DOI: 10.1016/j.tvjl.2008.02.015
Source: PubMed

ABSTRACT 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.

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