Effect of a GnRH Antagonist on Anti-Müllerian Hormone and Follicular Population in Anestrous Bitches

The objective of this study was to describe the effect of the third-generation GnRH antagonist, acyline, on ovarian follicular population and serum anti-Müllerian hormone (AMH) concentrations in female dogs. Four late anestrous bitches were administered 330 μg/kg SC acyline every 10 days for 60 days and followed up for 45 days. Blood samples were drawn on days −1, 15, 30, 45, 60, 75, 90 and 105 for AMH determination. Then, the females were ovariectomized and the excised ovaries were gross and histologically evaluated. The total ovarian follicles were counted. None of the female dogs presented estrus during treatment. Only one bitch presented an ovulatory estrus 20 days after treatment. The total number of ovarian follicles in these bitches was 96,200.10 ± 26,125.12, with 84.13%, 11.36%, 7.8% and 0.01% corresponding to primordial, primary, secondary and antral structures, respectively. Pretreatment AMH concentrations were 0.62 ± 0.17 ng/mL. This hormone varied throughout the study period (p < 0.01), diminishing to nadir values during treatment to then rapidly recover after its effect (0.2 ± 0.05 vs. 0.67 ± 0.22 ng/mL; p < 0.01). Acyline rapidly and reversibly prevented the initiation of cycling without affecting follicle count but diminishing serum AMH concentrations.Fil: Marchetti, Cynthia Dayana. Universidad Nacional de La Plata; Argentina. Universidad Católica de Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J.; ArgentinaFil: Grisolia Romero, Mariela Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Priotto, Marcelo Adrián. Universidad Católica de Córdoba; ArgentinaFil: Faya, Marcela Inés. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Católica de Córdoba; ArgentinaFil: Gobello, María Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata; Argentin

Long-term reproductive evaluation of a bitch neonatally treated with a gonadotropin-releasing hormone agonist

In mammals, high concentrations of gonadotropins are necessary early in life to reach a full-sized pool of ovarian follicles at the age of puberty. This case report describes the reproductive status of a 28-month-old, 9.1 kg, crossbred bitch (Bitch 1) which had been treated neonatally with 18.8 deslorelin acetate subcutaneously for contraceptive purposes. The female had just passed pubertal oestrus when hormones were measured and then spayed. The ovaries were histologically assessed. Two crossbred bitches were used for comparisons. Bitch 1's anti-Müllerian hormone (AMH) and progesterone serum concentrations were 0.35 and 16.7 ng/ml, respectively. The total number of ovarian follicles and proportions were normal and the number of primary and antral follicles was increased. These findings might suggest an enhanced recruitment of the follicle pool to the growing population which could be related to the relatively low AMH concentrations.Fil: Marchetti, Cynthia Dayana. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Católica de Córdoba; ArgentinaFil: Faya, Marcela Inés. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Priotto, Marcelo Adrián. Universidad Católica de Córdoba; Argentina. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Grisolia Romero, Mariela Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata; Argentina. Universidad Católica de Córdoba; ArgentinaFil: Gobello, María Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata; Argentin

Postponement of canine puberty by neonatal administration of a long term release GnRH superagonist

The objective of this study was to assess the efficiency and clinical safety of postnatal administration of a GnRH agonist on canine puberty postponement. Sexual steroids and histological gonadal changes were also described. Twenty-four littermate puppies were randomly assigned to: Deslorelin acetate 18.8 mg sc (DESLO; n = 12) or Placebo: sc (PLACE; n = 12) postnatally. The dogs were clinically and endocrinologically followed up until puberty when they were gonadectomized and their gonads histomorphometrically studied. Deslorelin postponed the age of puberty (72.7 ± 4.8 vs. 35.8 ± 1.9 weeks; P 0.1) independently of their group and pubertal status. None of the females had side effects while the 2 non pubertal DESLO males presented bilateral cryptorchydism. All the bitches ovulated at puberty (P > 0.1) and the 2 DESLO that were mated became pregnant. Deslorelin postponed basal serum sexual steroids up to puberty in both genders (P 0.05). It was concluded that postnatal deslorelin decreased sexual steroids reversibly postponing puberty in both genders without side effects in bitches and causing 2/6 of cryptorchydism and impairment of testicular histomorphometry in male dogs.Fil: Faya, Marcela Inés. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Marchetti, Cynthia Dayana. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Priotto, Marcelo Adrián. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Ciencias Básicas. Laboratorio de Nutrición Mineral y Fisiología Reproductiva; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Grisolía, M.. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Ciencias Básicas. Laboratorio de Nutrición Mineral y Fisiología Reproductiva; Argentina. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: D Francisco, Florencia Alina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Ciencias Básicas. Laboratorio de Nutrición Mineral y Fisiología Reproductiva; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Gobello, María Cristina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de Ciencias Básicas. Laboratorio de Nutrición Mineral y Fisiología Reproductiva; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin

Fecal Progestins Differentiate Pregnant From Nonpregnant Early Luteal Bitches

Considering the high perimplantation progesterone (P4) secretion that occurs in female domestic dogs, we hypothesize that fecal P4 concentrations distinguishes pregnant from nonpregnant early luteal bitches. The objective of this study was to compare fecal P4 metabolites in early pregnant vs. nonpregnant early luteal bitches. Eighteen 2-6 years of age, 5-15 kg, pure-bred bitches, that were followed up for breeding management, and 2 ovariectomized (OVX) bitches were included in this study. On pregnancy day 18-28, a single fecal sample was collected from each animal. Fecal samples were frozen at −20°C until analysis. Pregnancy diagnosis was carried out by ultrasonography on day 21. Fecal samples were also collected from the 2 OVX bitches. Fecal P4 metabolites were extracted as based on methods described by Brown et al. (2008) and, then, measured by an electrochemiluminescence immunoassay. Eleven bitches were pregnant (PREG) while 7 were non-pregnant (N-PR). Fecal P4 metabolites concentrations were 283.9 ± 60.4 and 102.7 ± 19.1 (ng/g; P < .05) for PREG and N-PR, respectively. Both values were higher than those of the OVX bitches (9.9±1.1; P < .05). This noninvasive technique to measure P4 metabolites in feces appears as a simple and noncostly alternative for early pregnancy diagnosis in the domestic dog. Further large scale studies are necessary before this test could be widely recommended.Fil: Faya, Marcela Inés. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Centro de Fisiología Reproductiva y Métodos Complementarios de Diagnóstico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Grisolia Romero, Mariela Eugenia. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Centro de Fisiología Reproductiva y Métodos Complementarios de Diagnóstico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Marchetti, Cynthia Dayana. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Centro de Fisiología Reproductiva y Métodos Complementarios de Diagnóstico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Priotto, Marcelo Adrián. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Ernst, Cecilia. Universidad Nacional de Río Cuarto; ArgentinaFil: Gobello, María Cristina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Centro de Fisiología Reproductiva y Métodos Complementarios de Diagnóstico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin

Testicular effects of a postnatal GnRH antagonist in domestic cats

The aim of this study was to describe the histological effects of two high postnatal doses of the potent third-generation GnRH antagonist, acyline in the domestic cat testicle. Secondly, the physical, endocrine, and steroidogenic findings of this pharmaceutical protocol are also reported. Twelve postnatal littermate male kittens were administered acyline in a dose of 2.2 mg/100 g SC weekly for 2 weeks (ACY; n = 6), or placebo (PL; n = 6). All the animals were followed up until puberty when they were castrated. Serial faecal samples were collected until the age of 10 weeks for testosterone (T) measurement. The kittens achieved puberty without either age (236.5 ± 19.7 vs. 221.7 ± 23.7 days) or body weight (3.05 ± 0.15 vs. 2.78 ± 0.28 kg, P > 0.05) differences between ACY and PL, respectively. Acyline suppressed faecal T concentrations for 3 weeks (P 0.05). Histological assessment of the testes showed that ACY cats presented a reduced height of the epithelium (P < 0.01) due to the diminished number of germinal cells accompanied by an enlarged luminal area (P < 0.01) with cellular debris (P < 0.01). The immunostaining of P450c17 also appeared partially diminished in ACY testes.Fil: Grisolia Romero, Mariela Eugenia. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Centro de Fisiologia Reproductiva y Metodos Complementarios de Diagnostico.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Faya, Marcela Inés. Universidad Católica de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Marchetti, Cynthia Dayana. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Centro de Fisiologia Reproductiva y Metodos Complementarios de Diagnostico.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Korber, Hanna. Leibniz Universitat Hannover.; AlemaniaFil: Goericke Pesch, Sandra. Leibniz Universitat Hannover.; AlemaniaFil: Gobello, María Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Centro de Fisiologia Reproductiva y Metodos Complementarios de Diagnostico.; Argentin

Anti-Müllerian hormone in queens: Serum concentrations and total ovarian follicle population

The objectives of this study were: a) To report anti-Müllerian hormone (AMH) serum concentrations in neonatal, pre and postpubertal female cats. b) To establish the relationship between serum AMH with either age and estrous cycle c) To correlate the total number of different ovarian follicle types with AMH in adult queens. A single blood sample was collected from 10 neonates (including 5 male), 15 prepubertal and 48 postpubertal female cats to measure AMH. Eight, 10, and 18 of this latter group were in follicular (FP), luteal phase (LP), and anestrus (AN), respectively. The total number of each follicle type was histologically counted using the Gougeon and Chainy (1987) formula in a subgroup of 10 adult queens. Overall AMH mean of these the female cats was 6.31 ± 0.54 ng/mL. The neonatal females had lower AMH serum concentrations than their male littermates (2.56 ± 0.49 vs. >23 ng/mL; P 0.05). A high correlation was only found between small antral follicles and AMH concentrations (r = 0.85; P < 0.01). It was concluded, that AMH can provide an indirect, reliable marker for the assessment of ovarian follicle size and functionality. Age as well as pubertal state should be considered when evaluating AMH concentrations in this species.Fil: Lapuente Romero, Camila. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Centro de Fisiologia Reproductiva y Metodos Complementarios de Diagnostico.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Faya, Marcela Inés. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Blanco, Paula Graciela. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Centro de Fisiologia Reproductiva y Metodos Complementarios de Diagnostico.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Grisolia Romero, Mariela Eugenia. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Centro de Fisiologia Reproductiva y Metodos Complementarios de Diagnostico.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Marchetti, Cynthia Dayana. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Centro de Fisiologia Reproductiva y Metodos Complementarios de Diagnostico.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Gobello, María Cristina. Universidad Nacional de la Plata. Facultad de Cs.veterinarias. Centro de Fisiologia Reproductiva y Metodos Complementarios de Diagnostico.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin

Evaluation of Long-Term Effects of the Gonadotrophin-Releasing–Hormone Antagonist Acyline on Domestic-Cat Growth

Acyline contraception has been described in cats, but few data are available on the drug's long-term effect on growth. The relevant data cover until puberty with no radiographic description. We investigated the radiographic parameters throughout bone growth in order to more completely determine the drug's safety. Thirteen male and 12 female cats were studied, with the kittens being randomly assigned to one of the following groups within the first 24 hours of birth: ACY, subcutaneous acyline, 33 µg/100 g, which injection was repeated weekly until age 3 months; or CO, untreated control. Body measurements were recorded weekly and radiographic parameters obtained from monthly radiographs of the antebrachium. In the ACY and CO male and female kittens, the body weight, withers height, and body length plus the age at the end of body growth and radial growth remained similar throughout the study (P>.05). Both female groups finished radial growth before the males (P<.05). The ACY females evidenced a longer radial length between the eighth and 28th weeks (P<.05). All groups closed their proximal and distal physes within the normal ranges described for the species. The bone-cortex width was lower in the ACY vs. the CO animals at weeks 52 and 60 in the males and at weeks 24, 48, 52, and 56 in the females (P<.05) The transient greater radial length and lower bone-cortex thickness observed in the treated cats were compensated for at the end of growth with no adverse clinical effects being observed. In conclusion, acyline as a contraceptive did not evidence a permanent or severe effect on domestic-cat growth.Fil: Grisolia Romero, Mariela Eugenia. Universidad Católica de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Marchetti, Cynthia Dayana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Católica de Córdoba; ArgentinaFil: Priotto, Marcelo Adrián. Universidad Católica de Córdoba; ArgentinaFil: Rodríguez, Marcelo. Universidad Nacional del Centro de la Provincia de Buenos Aires; ArgentinaFil: Gobello, María Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Furlan, Paulina. Universidad Católica de Córdoba; ArgentinaFil: Faya, Marcela Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Católica de Córdoba; Argentin

Physical, histological, endocrinological and steroidogenical evaluation of male cats postnatally exposed to sexual steroids

To test the hypothesis that postnatal sexual steroids induce an impairment of domestic male cat reproductive function, this study describes the physical, endocrine, steroidogenical and histological effects of a single, high dose of a postnatal sexual steroid in this species. Twenty male kittens were randomly assigned within the first 24 h of birth to: Testosterone enanthate 12.5 mg sc (TE; n = 8), medroxyprogesterone acetate 10 mg sc (MA; n = 6), or Placebo sc (PL; n = 6). The cats were followed until puberty when they were castrated. Kittens achieved puberty without age differences among groups (P > 0.05). Two MA cats presented abnormal testicular descent. Histological evaluation of the MA (P 0.05). It was concluded that the postnatal progestagen initially suppressed the gonadal axis and caused an impairment of spermatogenesis and testicular descent at puberty. Androgen treatment caused downregulation of the final steroidogenic cascade.Fil: Grisolia, M.. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Faya, Marcela Inés. Area de Ciencias Agrarias, Ingeniería, Ciencias Biológicas y de la Salud de la Universidad Católica de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Marchetti, Cynthia Dayana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: López Merlo, Mariana Lucía. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: D Francisco, Florencia Alina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Bellini, Maria Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Gobello, María Cristina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin