Cristina Gobello

Universidad Nacional de La Plata | UNLP · Center of Reproductive Physiology

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 d...

Domestic felids (Felis catus) have been traditionally categorized as seasonal polyestrous with induced ovulation. Thus, the ability to augment or distribute the number of litters born throughout the year would offer a desirable advantage. Artificial-light regimens have been used to overcome seasonal variations in this species. Understanding the mec...

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...

The jaguar (Panthera onca), the largest felid in the Americas, has been classified by IUCN as ‘near-threatened’. The purpose of this review was to gather the current knowledge on jaguar reproduction. Information from over forty-five sources has been selected. Jaguars have been classified as polyestrous with generally an induced ovulation, with a mo...

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 we...

Monitoring the treatment outcome of canine cystic endometrial hyperplasia‐pyometra complex (CEH‐P) is essential to identify nonresponding patients who might require a rapid intervention to avoid life‐threatening conditions. Uterine artery Doppler characterization may contribute to monitoring medically treated CEH‐P, but published studies are curren...

In mammals, spermatogenesis is a complex and cyclic process in which a spermatogonia turns into a highly differentiated cell: the spermatozoa. Spermatogenesis comprises proliferation of spermatogonia (spermatocytogenesis), meiosis of spermatocytes, and finally differentiation of spermatids into spermatozoa (spermiogenesis). This review summarizes t...

Objectives The aim of this study was to evaluate two-dimensional and Doppler ultrasonographic changes of the ovary and uterus during estrus and the early post-estrus period in domestic cats. Methods Two-dimensional and Doppler ultrasonographic evaluations of the ovaries and uterus were performed in seven queens on days 1, 3 and 5 of estrus, and 5...

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 a...

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 postnatally with 18.8 deslorelin acetate SC for contraceptive purposes. The...

Canine (Canis familiaris) pseudocyesis, pseudopregnancy, false pregnancy or nervous lactation is a frequent syndrome observed in non-pregnant, late diestrous or early anestrous females that is characterized by different degrees of mammary gland enlargement, maternal behavior and lactation. Further education about this frequent canine physiological...

Introduction The aim of this study was to evaluate cardiac morphology, indices of systolic and diastolic function, systolic blood pressure (SBP), and uterine artery resistance index (RI) during normal feline pregnancy. Animals; Materials and Methods Twenty domestic short-hair pregnant queens, weighing 2.4–3.9 kg. Animals were assessed by two-dimen...

Considering the high perimplantation progesterone (P4) secretion that occurs in female domestic dogs, we hypothesize that fecal P4 concentrations distinguishes pregnant from non-pregnant early luteal bitches. The objective of this study was to compare fecal P4 metabolites in early pregnant vs. non pregnant early luteal bitches. Eighteen 2 to 6 year...

The aims of this study were: to ultrasonograhically describe and compare testicular parenchyma echogenicity and heterogeneity using digital image analysis in: I) prepubertal (PREP), peripubertal (PERI) and mature (MAT) cats; II) Normal and abnormal mature felids. Secondary, the relationships between histomorphological and ultrasonographic attribute...

The aim of this study was to compare uterine and umbilical artery blood flow and fetal heart rate (FHR) in small, medium and large body weight (BW) dogs during the second half of pregnancy. Purebred pregnant bitches were assigned to one of the following groups according to their BW: small (S; ≤10 kg), medium (M; 11-25 kg) and large (L; >25-45 kg)....

The objectives of this article were: a) To describe the effect of a single administration of the third generation GnRH antagonist, acyline, on canine benign prostatic hyperplasia (BPH) b)To quantitatively compare parenchyma echogenicity, heterogeneity (SD echogenicity) and blood flow in hyperplastic and treated prostate glands. Seven mixed bred dog...

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...

The aim of this study was to describe the seminal, histomorphological and hormonal effects of the oral indenopyridine RTI-4587-073(l) on feline testicle. Clinical side effects were also recorded. Sixty testicles of 30 adult cats that had been treated (d 0) with RTI-4587-073(l) 12.5 mg/kg PO and randomly hemiorchiectomized twice on: day -14 (n = 8),...

The aim of this study was to evaluate two‐dimensional and Doppler ultrasonographic changes of feline ovaries before and during puberty. Nine, 3‐month‐old female cats were followed until puberty (Day 1). Two‐dimensional and Doppler ultrasound evaluations of the ovaries were carried out on Days ‐50, ‐20, ‐7 and 1. Longitudinal and transverse sections...

Contents The aim of this study was to compare uterine two‐dimensional and Doppler ultrasonographic parameters in queens suffering from pyometra from those in early pregnancy. Secondly, the effect of the presence of clinical signs of systemic illness on these parameters was also described. Fourteen post‐oestrous queens, with uterine luminal content...

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...

The objectives of this study were to evaluate the uterine artery blood flow during the second half of normal pregnancy in small breed dogs and to determine the RI reference values of this artery in these bitches. Fifty-two, 1.5-6.5 kg, purebred healthy pregnant bitches were included in this study. Doppler ultrasonographic examinations of the uterus...

The aim of this study was to evaluate echocardiographic and electrocardiographic parameters during the normal canine postpartum period. Twenty clinically healthy pregnant bitches of toy breeds (11 Miniature poodles, five Yorkshire terriers, two Maltese terriers and two Bichons Frises) were evaluated on days −3, 3, 10, 17, 24, 38, 52 and 80 relative...

In this study it was determined the progression of uterine gland development from late gestation to puberty in domestic felids. Cell proliferation patterns for luminal (LE), glandular epithelium (GE) as well as stroma (S) were also described. Twenty-four uteri from female kittens: 45 and 65 days of gestation and 1 to 5, 8, 12, 16, 20 and 24 weeks p...

The aim of this study was to describe resistance index (RI) and systolic/diastolic ratio (S/D ratio) of uterine and umbilical arteries in an experimental model of abnormal pregnancy in felids. On days 30 to 35 (32 ± 2.9) after mating, 20 domestic short-hair pregnant queens were randomly assigned to one of the following treatment groups: a treated g...

To test the hypothesis that in domestic cats, postnatal androgens induce sterility, the aims of this study were to describe the reproductive effects and the clinical safety of a postnatal administration of a long term release androgen in this species. Thirteen newborn littermate female kittens were randomly assigned to one of the following treatmen...

Doppler ultrasound is a useful diagnosis tool to evaluate uterine blood flow in different canine reproductive states. The aim of this study was to describe and compare uterine blood flow in bitches suffering from cystic endometrial hyperplasia (CEH) and CEH-pyometra complex. Ninety diestrous bitches were clinically, hematologically and ultrasonogra...

In mice and sheep, neonatal administration of progesterone or progestins inhibited development of uterine glands. The aims of the present study were (1) to describe uterine gland development on postnatal Days 6 to 8 and (2) to evaluate the effects of a single postnatal administration of a progestin on reproduction and adult uterine glands morpholog...

To assess the effect of a single supraphysiological postnatal administration of a progestagen on uterine glands in dogs, 10 females were randomly assigned to: Medroxyprogesterone acetate 35 mg (MPA; n=6) or Placebo (n = 4) within the first 24 h of birth. The safety of the treatment was also evaluated. A transient mild clitoris enlargement appeared...

To describe the effect of the third-generation gonadotropin-releasing hormone antagonist acyline in the treatment of 4 diestrous bitches with the cystic endometrial hyperplasia-pyometra complex. The 4 bitches were treated with 330μg/kg of subcutaneous acyline on day 0 and antibiotics, and followed up for 2 weeks. One closed-cervix case showed cervi...

The aim of this study was to describe bidimensional and Doppler ultrasonographic changes of uterine involution during normal feline puerperium. Secondary, the postpartum vaginal discharge was described. Twelve pregnant female cats were included in this study. After queening, vulvar discharge was grossly and microscopically examined daily. Bidimensi...

In postnatal domestic cats, GnRH agonists suppressed fecal concentrations of sexual steroids and delayed puberty. The aim of this study was to describe the gross and microscopic morphometric effects of a single administration of the GnRH agonist, deslorelin acetate, on the gonads of postnatally treated cats. Twenty-seven postnatal male (n = 14) and...

Insufficient knowledge has been acquired regarding the prepubertal and pubertal periods of domestic canids. Until further information becomes available, a better standardization of the definitions, a careful and complete description of experimental variables and end points is necessary to diminish experimental bias in published trials. The aim of t...

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 sc (AG; n = 16), acyline 33 μg/100g sc weekly for 3 months (...

The aim of this study was to describe Doppler parameters of uterine, umbilical, fetal abdominal aorta, fetal renal and fetal internal carotid arteries, as well as fetal heart rate (FHR), during normal feline gestation. Fifteen, 1-4 years of age, weighing 2.5-3.9 kg, domestic short-hair pregnant queens, which were born in our Institutional cat colon...

The purpose of this report is to describe (1) the training of domestic cats in ejaculation into an artificial vagina (AV), (2) alkaline phosphatase (AP) concentrations in whole ejaculates, and (3) the in vitro effect of a skimmed-milk plus egg yolk (SM-Y) extender on feline spermatozoa incubated at 4ºC. Five post-pubertal cats were trained to ejacu...

The aims of this study were to assess and compare the effect of skim milk with (MEY) and without (SMI) egg yolk on canine spermatozoa incubated at 4(circle)C in vitro and to evaluate the efficacy of MEY in vivo. Also, the effect of semen cooled storage before freezing was also evaluated in vitro. The ejaculates of 10 dogs were collected, pooled, ce...

The aim of this study was to describe Doppler ultrasonographic changes of uterine arteries during normal canine puerperium. Eight healthy, pure-bred bitches, were ultrasonographically assessed during the postpartum period on Days -3, 3, 10, 17, 24, 38, 52 and 80 (Day 0 defined as the day of parturition). Total horn diameters (TD) and endometrium th...

The aim of this article was to describe the time course of prepubertal sexual steroids in domestic cats. Fourteen newborn kittens were followed up until puberty (physical, behavioral, and hormonal changes). Fecal testosterone [T; males] and E estradiol 17-β [E2; females] concentrations were analyzed by repeated measures ANOVA and two consecutive ti...

Las mejoras en los programas reproductivos y las condiciones de vida en los zoologicos han ocasionado un exceso de animales en relacion a las posibilidades de espacio y mantencion. Ademas, se hace necesario evitar el inbreeding que se produce en grupos poblacionales cerrados y tambien preservar las interacciones sociales manteniendo agrupados los a...

Contents Gonadotrophin‐releasing hormone ( G n RH ) stimulates the pituitary secretion of both luteinizing and follicle‐stimulating hormones, and thus controls the hormonal and reproductive functions of the gonads. G n RH analogs, which include agonists and antagonists, have been produced by amino acid substitutions within the native G n RH molecul...

Contents The aim of this study was to describe the effect of unilateral orchidectomy on testicular characteristics of mature domestic cats. Five, 1‐ to 2‐year‐old, cross‐bred male cats were unilaterally orchidectomized on day 0 (right) and day 60 (left). The testes were processed for histological and immunohistochemical evaluation and groups compar...

The objective was to verify maternal hemodynamic differences between normal and abnormal pregnancies in dogs. Brucella-negative pregnant bitches (n = 31) were retrospectively classified into abnormal (which had either their pregnancy interrupted between Days 52 and 60 or perinatal death of more than 50% of the litter; n = 14) and normal (which had...

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 implant...

The aim of this study was to describe the effects of a single dose of the gonadotrophin releasing hormone (GnRH) antagonist acyline on testicular characteristics of the domestic cat. Twelve mature cats were orchidectomised unilaterally (right testis) on Day -7 (n=7) or Day 15 (n=5). On Day 0, 330 μg/kg acyline was administered s.c. to all the anima...

Domestic cat seasonality between the tropics and the arctic zones is scarcely described and results are inconsistent. The aim of this study was to describe domestic feline seasonal patterns under a natural temperate photoperiod. A total of 372 estrous cycles were studied in 34 post pubertal cats during 900 days. The queens were housed in a cat colo...

The objective of this study was to describe testosterone (T) response to GnRH challenge in antagonist-treated dogs over a 30-day period. Eight mongrel dogs were randomly assigned to either the GnRH antagonist acyline 330 μg/kg sc (ACY; n = 4) or a placebo group (PLA; n = 4). The dogs were serially challenged with the GnRH agonist, buserelin 0.2 μg/...

The aim of this study was to describe the canine electrocardiographic changes in the course of normal and abnormal pregnancy. Twenty-three Brucellosis-negative pregnant bitches were retrospectively classified as normal (n = 12) or abnormal (n = 11). A control group of non-pregnant dioestrous bitches (n = 10) was also included. Normal pregnant femal...

The aim of this study was to describe the changes of uterine artery, umbilical artery and fetal abdominal aorta, renal and internal carotid arteries blood flow in abnormal canine pregnancy. Twenty-two, Brucella-negative pregnant bitches were retrospectively classified into abnormal (which had either interrupted their pregnancy between days 52 and 6...

The objective was to assess the efficacy and safety of long-term administration of melatonin (either as an implant or given orally) on interestrus intervals in domestic cats. Additionally, the effect of melatonin implants on puberty postponement was studied. For these purposes, two randomized controlled trials were conducted. In the first, 68 inter...

Desmopressin (DDAVP) is a vasopressin peptide analog with hemostatic properties that has been successfully used during surgery in patients with bleeding disorders. Recently published experimental and clinical data indicate that perioperative administration of DDAVP can minimize spread and survival of residual mammary cancer cells. The central aim o...

Benign prostatic hyperplasia (BPH) and its infectious complications, i,e. chronic prostatitis, are very prevalent diseases in the aging dog. Although biopsy offers the definitive diagnosis, ultrasound guided fine needle aspiration (US-FNA) cytology is a safe and rapid tool for the presumptive diagnosis of prostatic conditions. The objective of this...

The aim of this study was to describe changes in cardiac morphology, systolic function and some peripheral hemodynamic parameters during normal pregnancy in dogs. Twenty healthy bitches, 10 pregnant (PG) and 10 non-pregnant controls (CG), were evaluated every 10 days using echocardiography from day 0 of the estrus cycle to parturition or to day 65...

Relatam-se o primeiro isolamento de herpesvirus canino 1 (CaHV-1) e a localização atípica das lesões vesiculares associadas a este vírus na Argentina. A amostra foi recuperada de lesões vesiculares, localizadas na parte interna da coxa direita, em uma fêmea de raça Labrador. A cadela tinha quatro anos de idade e era de propriedade privada. O primei...

La técnica de inmunohistoquímica descrita por Walker y col. (1998) y Mote y col. (2001) es de utilidad para la determinación de receptores de estrógenos y de progesterona en tumores mamarios de la hembra canina. Existe bastante controversia respecto al porcentaje de receptores de estrógenos y de progesterona, con valor pronóstico o predictivo en tu...

Immunohistochemical technique described by Walker et al. 1998 and Mote et al. 2001 is useful for the determination of estrogen and progesterone receptors in canine mammary tumors. There is considerable controversy regarding the percentage of estrogen and progesterone receptors that having prognostic or predictive value in malignant tumors in dogs b...

Two experiments were conducted to investigate the effects of the GnRH antagonist acyline (330 microg/kg, given sc) on ovarian follicular development and ovulation, as well as on pregnancy maintenance in domestic cats. In the first experiment, seven queens in proestrus (total of 24 proestrus periods), were randomly assigned to treatment with either...

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 domest...

Contents Gonadotropin‐releasing hormone (GnRH) antagonists are particularly useful when a rapid inhibitory effect on the gonadal axis is required. The aim of this study was to test the efficacy and clinical safety of a low and high dose of the third generation GnRH antagonist, acyline, on pregnancy termination in female dogs. The effect of the anta...

Contents The aim of this study was to describe the changes in the resistance index (RI) and systolic/diastolic ratio ( S / D ) of the uterine arteries during mid‐pregnancy abortion induction in the dog. Sixteen 30–35 day pregnant bitches were randomly assigned to either a pharmacological protocol to interrupt gestation (n = 8) or were used as untre...

Contents This study compared the efficiency of the aromatase inhibitor, anastrazole, with the antioestrogenic receptor blocker, tamoxifen, on normal (NRL) and hyperplastic prostate glands. Forty healthy dogs were classified as NRL (n = 18) or abnormal (ABN) with benign prostate hyperplasia (n = 22). The dogs were randomly assigned to one of the fol...

Gonadotrophin-releasing hormone (GnRH) antagonists may have a future role in the control of canine reproductive function. In this study, the effects of a single dose of the potent GnRH antagonist, acyline, on serum concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone (T) were evaluated in male dogs. Blood...

The aim of this article is to review the current knowledge of Doppler ultrasound in canine pregnancy. A brief introduction of Doppler principles and their applications in human obstetrics is also included. A review of the peer-reviewed published literature was conducted of the articles pertaining to the use of Doppler ultrasound in canine pregnancy...

Las metástasis pulmonares de tumores mamarios son generalmente la causa de muerte en las mascotas que padecen una neoplasia de glándula mamaria. Esto marca la importancia en la búsqueda de nuevos tratamientos, enfocados a la modulación de blancos moleculares, con una acción predominante en la estabilización o regresión de la enfermedad metástasica....

To test the efficacy and clinical safety of a low and high dose of the GnRH antagonist, acyline, on estrous cycle interruption and anovulation in female dogs, 20 proestrous (<3d) bitches were randomly assigned to one of the following pharmacological protocols (given sc): acyline 110 microg/kg (ACY-L; n=6); acyline 330 microg/kg (ACY-H; n=8); or pla...

A non-pharmaceutical, dietary option may be useful to manage clinical pseudopregnancy (PSP). To describe the effect of short-term food restriction on canine PSP, 16 privately owned, overtly pseudopregnant bitches were randomly assigned to one of the following groups: Limit-fed (increasing amounts of a restricted maintenance: 50%, 40%, 30% restricti...

The primary objective was to assess the effects and clinical safety of a single high-dose of the third generation GnRH antagonist, acyline, on testicular characteristics in male dogs. Seven dogs were followed up weekly for six, 2-week periods (-2, -1, 1, 2, 3 and 4). At the end of the second period, they were given acyline (330 microg/kg sc). Respo...

Desmopressin (1-deamino-8-d-arginine vasopressin, also known as DDAVP) is a safe haemostatic compound capable of inhibiting lymph node and lung metastasis in a mouse model of mammary tumour manipulation and surgical excision. The aim of this study was to test the efficacy and safety of perioperative DDAVP (1microg/kg) in surgically treated bitches...

Gonadotropin-releasing hormone (GnRH) analogs, which include agonists and antagonists, have been produced by amino acid substitutions of the native GnRH molecule to create greater potency and longer duration of effectiveness. The aim of this article was to review the pharmacological effects and the existing clinical literature of new GnRH analogs,...

Over the last 10 years, new drugs have been applied to canine reproduction, widening the spectrum of therapeutic possibilities for diseases that were previously surgically treated, and facilitating better control of the estrous cycle and fertility. Some are not approved for use in dogs; their use is experimental and further clinical trials are nece...

Little is known about serum prolactin (PRL) concentrations and secretion patterns in male dogs. Blood samples (n = 65) were collected from crossbred dogs and from Beagles and German Shepherd dogs to describe the PRL reference range, and from five male Beagles at 15-min intervals for 6 h (n = 24 samples/dog) to describe the ultradian rhythm of this...

Cystic endometrial hyperplasia-pyometra (CEH-P) complex is a progesterone-dependent disease that requires medical treatment in bitches intended for breeding. To test the efficacy and safety of a combined protocol and to assess the effect of age, stage of cycle, previous steroid hormone administration and parity on treatment, 29 bitches diagnosed wi...

To assess the efficacy and safety of a combined cabergoline and cloprostenol protocol to terminate third-quarter pregnancy, 22 pregnant bitches that ranged from 35 to 45 days after mating were randomly assigned to a treatment group (n=13) or to an untreated control group (n=9). The animals were monitored for 12 days, and pregnancy termination was c...

The objective of this study was to test the efficacy and safety of a short-term progestin treatment administered at two different times to prevent estrous induction in response to the administration of an implant releasing the GnRH agonist, deslorelin acetate (DA), in anestrous bitches. Interestrous intervals (IEI) observed prior to and post DA wer...

Body temperature responses and the timing of abortions were evaluated in pregnant bitches with the anti-progestin aglepristone. Fifteen purebred and crossbred, 25-45 days pregnant, were included in this study and seven untreated bitches at the same stage of pregnancy served as controls. Treated bitches were administered two applications of aglepris...

A meta-analysis of growth hormone data showing similar double amplitudes of 36 and 34% of the mean from the fit of cosine curves with periods of 1.3 and 1.0 year, respectively, suggests the desirability of analyzing available time series on variables of interest in biomedicine, to explore heretofore unknown longer-than-yearly cycles that may intera...

Tamoxifen is a synthetic, nonsteroidal Type I antiestrogenic compound that competitively blocks estrogen receptors with a mixed antagonist-agonist effect. The manifestation of these different actions depends on each species, organ, tissue and cell type considered. Very little is known about the effect of antiestrogens in dogs. The objectives of thi...

Two consecutive interestrous intervals (n=46) were recorded in 23 bitches of different breeds. At varying times after day 100 from the onset of the second proestrus, cabergoline (5 microg/kg per os q 24 hours) was administered from early (n=11), mid- (n=10), and late (n=2) anestrus until 2 days after the beginning of the following proestrus. Intere...