Effects of treatment with buserelin on plasma concentrations of oestradiol and progesterone and cycle length in the cow.
Treatment of cows with 10 micrograms of the gonadotrophin releasing hormone (GnRH) analogue, Buserelin (Receptal; Hoechst) 12 days after mating results in a 12% improvement in conception rate (Drew & Peters, 1991). We have now investigated the endocrine effects and possible mechanism of action underlying this effect. Treatment of cyclic cows (n = 5) with Buserelin on days 11 and 13 did not affect cycle length or plasma concentration of progesterone, but did significantly (P < 0.05) reduce plasma oestradiol concentration from day 12-16. We conclude that the Buserelin treatment acts by causing a fall in plasma oestradiol which results in a reduction in the strength of the luteolytic drive, improving the chance of an embryo being able to prevent luteal regression.
Mann
G E
GE
Department of Physiology and Environmental Science, University of Nottingham Sutton, Bonington, Loughborough, UK.
Lamming
G E
GE
D000818:Animals; D002064:Buserelin / Q000494:pharmacology*; D002417:Cattle / Q000097:blood* / Q000502:physiology; D004958:Estradiol / Q000097:blood*; D004971:Estrus / Q000187:drug effects*; D005260:Female; D005298:Fertility / Q000187:drug effects; D011374:Progesterone / Q000097:blood*
D011374:Progesterone; D004958:Estradiol; D002064:Buserelin