title: Effect of GnRH analogs in postnatal domestic cats.
abstract: The aim of this study was to reproductively assess the clinical and hormonal effects of a GnRH agonist (AG) and an antagonist (AN) administered during the postnatal period in domestic cats. Forty-eight male and female postnatal kittens were randomly assigned to deslorelin acetate 1.6 mg subcutaneous (AG; n = 16), acyline 33 μg/100 g subcutaneous weekly for 3 months (AN; n = 16), or control (CO; n = 16) which remained untreated. The cats were followed up (behavioral observation, physical examination, fecal sexual steroid determinations, mating test, and pregnancy diagnosis) up to puberty. Puberty was delayed (weeks) in the AG animals (62.9 ± 3.5; P < 0.01) but not in the AN (15.5 ± 1.7; P > 0.05) when they were compared with CO kittens (13.4 ± 0.4). Fifteen (15/16) of the AN and CO animals, and only 11 of 16 cats of the AG group were fertile (P > 0.1). No differences were found in body weight (P > 0.1) and measurements (P > 0.1), libido (P > 0.1) and in the appearance of side effects (P > 0.1; except a pyometra in an AG female) among groups. In both AG- and AN-treated males (testosterone; P < 0.01) and females (estradiol-17β; P < 0.01) fecal hormone concentrations were lower than in CO group during the first five postnatal weeks but not later. It is concluded that the neonatal administration of these AG and AN decreased fecal sexual steroids during the first postnatal weeks causing, the agonists but not the antagonist, a significant, reversible delay in puberty appearance.
authors.affiliation: Laboratory of Reproductive Physiology, Faculty of Veterinary Medicine, National University of La Plata, La Plata, Argentina.
authors.forename: A
authors.initials: A
authors.lastname: Carranza
authors.affiliation: Laboratory of Reproductive Physiology, Faculty of Veterinary Medicine, National University of La Plata, La Plata, Argentina; Small Animal Clinics, Catholic University of Cordoba - CONICET, Cordoba, Argentina.
authors.forename: M
authors.initials: M
authors.lastname: Faya
authors.affiliation: Laboratory of Reproductive Physiology, Faculty of Veterinary Medicine, National University of La Plata, La Plata, Argentina.
authors.forename: M Lopez
authors.initials: ML
authors.lastname: Merlo
authors.affiliation: Laboratory of Reproductive Physiology, Faculty of Veterinary Medicine, National University of La Plata, La Plata, Argentina.
authors.forename: P
authors.initials: P
authors.lastname: Batista
authors.affiliation: Laboratory of Reproductive Physiology, Faculty of Veterinary Medicine, National University of La Plata, La Plata, Argentina. Electronic address: cgobello@fcv.unlp.edu.ar.
authors.forename: C
authors.initials: C
authors.lastname: Gobello
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001835:Body Weight; D002415:Cats; D003267:Contraception / Q000379:methods / Q000662:veterinary*; D005260:Female; D012739:Gonadal Steroid Hormones / Q000378:metabolism; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists / Q000037:antagonists & inhibitors; D008297:Male; D009842:Oligopeptides / Q000494:pharmacology*; D012741:Sexual Maturation / Q000187:drug effects; D013997:Time Factors; D017329:Triptorelin Pamoate / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D012739:Gonadal Steroid Hormones; D009842:Oligopeptides; D017329:Triptorelin Pamoate; D007987:Gonadotropin-Releasing Hormone; C109238:acyline; C066438:deslorelin
keywords: Feline; GnRH agonist; GnRH antagonist; Neonate