Effect of a GnRH antagonist on GnRH agonist?implanted anestrous bitches

VALIENTE C, DIAZ JD, ROSA DE, MATTIOLI G, GARCÍA ROMERO G, GOBELLO C.

THERIOGENOLOGY

ELSEVIER SCIENCE INC

Lugar: Amsterdam; Año: 2009 vol. 72 p. 926 - 929

0093-691X

Various combinations of gonadotropin-releasing hormone (GnRH) antagonists and long-acting GnRH agonists have been assessed in several species to prevent the "flare-up" effect that agonists cause on the pituitary-gonadal axis. To determine the effect of a single administration of the GnRH antagonist acyline in anestrous GnRH agonist-implanted domestic bitches, 19 dogs (canis familiaris) were randomly assigned to receive either 10mg sc deslorelin acetate (DA; n=6) or DA combined with 330 microg/kg sc acyline within the first 48 h (DA & ACY; n=13). These bitches were examined daily for detection of posttreatment flare-up, manifested as an estrous response during the month after treatment. In the DA and DA&ACY groups, an estrous response was detected in 6 of 6 and 9 of 12 (P0.1). It was concluded that the current antagonist protocol prevented initial ovarian stimulation in one quarter of the treated dogs, whereas the stimulation period was postponed and ovulation was inhibited in approximately half of the remainder.