Long-term-release GnRH agonists postpone puberty in domestic cats.

The aim of this study was to assess the efficacy and safety of deslorelin acetate implants on domestic queen puberty postponement. Thirty, 114.4 ± 12.7 days old, 1.5 ± 0.1 kg prepubertal crossbred female cats were included in this study. The animals were kept under a positive photoperiod and randomly assigned to deslorelin acetate 4.7 mg SC implants (n = 15) or to a non-treated control group (n = 15). The queens were followed up daily and weighed weekly until puberty. Vaginal cytology was also carried out three times a week. Puberty was diagnosed by the presence of the typical oestrous behaviour and vaginal cytology findings. At puberty, ovariectomy was performed and the gonads grossly described. Age (281.2 ± 21.6 vs 177.8 ± 10.8; p < 0.01) but not weight (2.6 ± 0.1 vs 2.5 ± 0.1; p > 0.1) at puberty differed between the deslorelin and control groups, respectively. One deslorelin-treated female showed an oestrous response and another showed clinical signs of pyometra after the implants. Deslorelin-treated ovaries appeared small, while control gonads were normal. It was concluded that long-term-release deslorelin, administered at approximately 50% adult body weight, postponed feline puberty without altering growing rate.

[1]  M. Driancourt,et al.  Controlled delivery of a GnRH agonist by a silastic implant (Gonazon) results in long-term contraception in queens. , 2009, Reproduction in domestic animals = Zuchthygiene.

[2]  S. Bertelloni,et al.  Treatment of central precocious puberty by GnRH analogs: long-term outcome in men. , 2008, Asian journal of andrology.

[3]  C. Gobello New GnRH analogs in canine reproduction. , 2007, Animal reproduction science.

[4]  M. Driancourt,et al.  Treatment with a subcutaneous GnRH agonist containing controlled release device reversibly prevents puberty in bitches. , 2006, Theriogenology.

[5]  T. Trigg,et al.  Short-term progestin treatments prevent estrous induction by a GnRH agonist implant in anestrous bitches. , 2006, Theriogenology.

[6]  D. Thompson,et al.  Prolonged interovulatory interval and hormonal changes in mares following the use of Ovuplant™ to hasten ovulation , 2000 .

[7]  P. Roche,et al.  GnRH Antagonist Effects on Follicle Number and Size in Rat Neonates and Infants , 1999 .

[8]  H. Fraser,et al.  Blockade of the neonatal rise in testosterone by a gonadotrophin-releasing hormone antagonist: effects on timing of puberty and sexual behaviour in the male marmoset monkey. , 1994, The Journal of endocrinology.

[9]  L. Janssens,et al.  Bilateral flank ovariectomy in the dog -surgical technique and sequelae in 72 animals , 1991 .

[10]  H. Dijkstra,et al.  Effects of LHRH antagonist administration to immature male rats on sexual development , 1989, Physiology & Behavior.

[11]  J E Rivier,et al.  Gonadotropin-releasing hormone analog design. Structure-function studies toward the development of agonists and antagonists: rationale and perspective. , 1986, Endocrine reviews.