Deslorelin Group Research Articles

Effect of pre-treatment with deslorelin on the ovarian response of ewes superovulated with FSH.

This study evaluated the use of the GnRH agonist hormone, deslorelin, to control the follicular population before initiating multiple ovulation and embryo transfer (MOET) treatment. Twenty-four cross-bred Santa Inês ewes, aged between 2 and 4 years, were randomly assigned to either a control group (n = 11) or a treated group (n = 13). All ewes received an intravaginal device containing 60 mg of medroxyprogesterone acetate on day 0, and a new device on day 7, which remained in place until day 14. Additionally, the ewes were administered 125 μg of cloprostenol on day 7. The superovulatory treatment involved administering 200 mg of pFSH, divided into eight decreasing doses at 12-h intervals starting on day 12. On day 14, 300 IU of eCG was administered. In the deslorelin group, three doses of 100 μg of deslorelin were administered starting on day 3 after the insertion of the vaginal device, with subsequent doses given at 72-h and 144-h intervals. Natural mating was performed 36 h after the removal of the progesterone implant using males with proven fertility. Embryo collection took place on the 6th day after mating, and the recovered structures were quantified and evaluated for quality and developmental stage. Transrectal ultrasonography was conducted on days 12, 16 and 21 to evaluate the ovaries, specifically to assess the ovarian follicular population and the presence of the corpus luteum. Ewes in the control group had higher embryo recovery rates (p < .01) compared to the treated group (5.2 ± 0.8 vs. 1.1 ± 0.8), with differences observed primarily in the number of morulae. The number of corpus luteum observed during the laparotomy on day 21 was significantly higher (p < .01) in the control group (10.44 vs. 4.5 corpus luteum per ewe). Yet, the treated group had a significantly higher number of follicles (p < .05) on the first day of pFSH application (5.5 vs. 3.0 follicles per ewe). In conclusion, although the inclusion of deslorelin in the superovulation protocol resulted in increased synchronization of oestrus and follicle number, it did not lead to an increase in the number of corpus luteum or harvested embryos.

Efficacy and Safety of 4.7 mg Deslorelin Acetate Implants as a Neutering Option in Male Cats: A Large-Scale Multicentre Randomised Controlled Study.

This multicenter-controlled, double-masked randomized European study was conduc-ted to confirm both the efficacy and safety of a deslorelin implant in controlling fertility and sexual behavior in a large population of tom cats over a 12-month period. Among the 225 screened individuals, a total of 205 privately owned indoor intact male cats, aged 3 months of age or older, were randomly allocated to a deslorelin implant (n = 154) or to a negative control group (n = 51). After the screening visit performed between day (D)-14 and D-7, six additional visits were sche-duled on D0, D45, D93, D186, D279 and D372. Effects on testosterone, sexual behaviors, penile spines, testicular volume and intact male cat urine odor were assessed at every visit under masked conditions as regards to the treatment group. In addition, phone calls from the investigators to the owners were scheduled on D7 and then on a monthly basis whenever no visit was scheduled. Success was defined as an individual serum testosterone concentration below or equal to 0.10 ng/mL and was 77.9% at D45, 83.1% at D93, 84.4% at D186 and D279, and 61.7% at D372 in the deslorelin group, and 3.9% at D45, 5.9% at D93, 3.9% at D186, 7.8% at D279 and 3.9% at D372 in the negative control group. Testing for superiority was made stepwise from D45 to D372 upwards; the difference in success rates was significant from D45 to D372 (p < 0.001 for each time point). The mean testosterone concentration dropped from baseline in the deslorelin group, remaining below the set threshold of 0.1 ng/mL until D372. From D7 onwards, the mean sum score for sexual behaviors (including vocalization, urine marking, aggression and intact male cat urine odor) was significantly lower at each observation time point in the deslorelin group compared to the control group, where no decrease in scores was observed. The mean percent change to baseline of the testicular volume and the percentage of cats with a decreased visibility and adult appearance of penile spines were significantly lower in the deslorelin group as soon as D45. No relevant safety concerns were reported during the course of the study. The deslorelin implant Suprelorin® 4.7 mg (Virbac, Carros, France) is a safe and effective neutering option, inducing infertility over a 12-month period when administered to intact male cats aged between 3 months of age and 11 years of age. The implants also successfully reduced sexual behaviors (i.e., vocalization, urine marking, aggression), intact male cat urine odor, testicular volume and penile spine score for 1 year (372 ± 5 days).

Eficiência e acurácia de diferentes indutores de ovulação após a remoção do dispositivo de progesterona em vacas mestiças multíparas

Abstract The aim of this study was to verify the efficiency and ovulation time after the administration of different inducers for synchronization of ovulation in beef cows. One hundred and eight non-lactating cows were distributed into the control group (CG; untreated; n=28), estradiol benzoate (EB) group (EBG; n=28); 17 beta-estradiol (17ßE) group (17ßEG; n=28), and deslorelin (DES) group (DESG; n=24). On day minus 11 (D-11) of the protocol, the CG underwent application of cloprostenol and ultrasound examination (US); on D0, progesterone (P4) was inserted plus EB; on D7, cloprostenol was applied; on D9, P4 was removed and cloprostenol plus 400 IU of equine chorionic gonadotropin (eCG) was injected. The EBG was subjected to treatment identical to that of the CG, except on D10, when the cows received EB. The 17ßE was subjected to the same protocol used in the CG except for the administration of 17ßE on D10. And, the DESG was subjected to the same treatment as the CG, except on D10, when the group received DES acetate. Twelve hours after the administration of EB, 17ßE and DES, ovarian US were performed every 6 hours. The preovulatory follicle (POF) diameters measured before ovulation were 19.5; 14.7; 18.7 and 19.8 mm respectively for CG, EBG, 17ßEG and DESG; and the time intervals between inducer application and ovulation were 20.2; 18.9; 21.0 and 22.5 hours respectively. In conclusion, all ovulation inducers were efficient in promoting ovulation; the inducers caused ovulation between 18.9 and 22.5 hours; EB promoted ovulation in a shorter time (P&lt;0.05); 17ßE and DES showed greater variation in application/ovulation time between groups.

Evaluation of deslorelin implant on subsequent mammary tumors of rats (Rattus norvegicus)

ABSTRACT Background Mammary fibroadenomas are one of the most common tumors of female companion rats (Rattus norvegicus forma domestica). The objectives of this study were to determine if subcutaneous administration of a deslorelin implant following excision of fibroadenomas can prevent or delay development of additional mammary tumors and increase survival in companion rats. Methods Female intact client-owned rats with benign mammary tumors were divided into three groups: no implant (n = 10), placebo implant (n = 10), or 4.7 mg deslorelin implant (n = 10) placed within 2 months of tumor excision. Rats were monitored for subsequent mammary tumors for 10 months following treatment. Expression of estrogen α, progesterone, prolactin, and androgen receptors stained by immunohistochemistry in primary masses of rats included in the deslorelin-treated group was evaluated using the Allred scoring system. Results In the control non-implanted group, four of the 10 rats developed another mammary tumor, including one anaplastic carcinoma. In the control placebo group, five of the 10 rats developed another mammary tumor, including one ductal carcinoma. In the deslorelin-treated group, three of 10 rats developed another mammary tumor, including one adenocarcinoma. Median time between surgery and new mass detection did not differ significantly among groups (55 days in the deslorelin group vs. 77 days in the control placebo group, P = 0.25). Median survival times after surgery did not differ significantly among groups. No correlation was noted between receptor expression and response to treatment with deslorelin. Conclusions and clinical relevance Deslorelin implants placed within 2 months of benign mammary tumor surgical excision were not associated with a decreased risk of developing subsequent mammary tumors, nor with an increased survival in female rats. Further studies are needed to define useful adjunct therapy to surgery.

Association of Deslorelin and Sulpiride for Double Ovulation Induction in Mares

The aim of this study was to verify the effect of deslorelin and sulpiride association on double ovulation induction in mares. Ten mares were used for this study. Eight days after ovulation, luteolysis was induced and mares were submitted a daily ultrasonographic evaluation until observation of at least two follicles measuring between 20 and 25 mm. Animals were split in two experimental groups in a crossover study. In deslorelin (DES) group, the animals received 150 μg deslorelin, intramuscularly, every 12 hours, until the second largest follicle reached at least 33 mm in diameter, at which time ovulation induction was performed with 1.500 IU of human chorionic gonadotrophin, IV. In the DES + sulpiride (SULP) group, the treatment was performed in the same manner as in the DES group, associated with the administration of 1 g of sulpiride, orally, once daily until the time of ovulations induction. In both groups, ultrasound examinations were performed daily to evaluate follicular development and the detection of ovulations. Double ovulations were observed in 70% (7/10) of the animals of the DES group and 50% (5/10) of the animals in the DES + SULP group. The percentage of ovulations corresponding to the number of follicles developed was 81.8% (18/22) for the DES group and 79% (15/19) for the DES + SULP group, and no difference was observed between the groups (P > .05). We conclude that association of sulpiride with deslorelin acetate did not contribute to the increase in double ovulations in mares.

Effect of Deslorelin and/or Human Chorionic Gonadotropin on Inducing Ovulation in Mares During the Transition Period Versus Ovulatory Season

The objective of this study was to compare the rate of ovulation when deslorelin and/or human chorionic gonadotropin (hCG) was administered in mares in both the transition period and the ovulatory season. A total of 200 Paint Horses, Quarter Horses, and crossbred mares were used during the transition season (July to September) and the ovulatory season (October to February) of the southern hemisphere. The animals were divided into four groups. In the control group (n = 72), mares received 1 mL of saline; in deslorelin group (n = 171), 1.5 mg of deslorelin was administered by intramuscular (IM) injection; in hCG group (n = 57), 1,667 IU of hCG was administered IV; and in hCG + deslorelin group (n = 438), 1.5 mg of deslorelin (IM) and 1,667 IU of hCG (IV) were administered. The drugs were administered after follicles ≥35 mm in diameter were identified and grade III uterine edema was observed. At 48 hours after application, ultrasonography was performed to detect ovulation. During the transition period, the ovulation rates were 4.3% (control), 78.6% (deslorelin), 50% (hCG), and 73.3% (hCG + deslorelin). During ovulatory season, the ovulation rates were 16.4% (control), 68.8% (deslorelin), 60% (hCG), and 73% (hCG + deslorelin). There was no significant difference (P > .05) in the ovulation rate between the groups or the periods, except that the control group was lower than all others. Furthermore, both hCG and deslorelin are viable options for inducing ovulation during the transition period before ovulation season.

Induction of double ovulation in mares using deslorelin acetate

This study aimed to determine whether deslorelin acetate could induce double ovulation in mares. In Experiment 1, eight mares were treated with prostaglandin on Day 8 (D8) after ovulation, then treated with saline or with 100μg of a controlled-release formulation of deslorelin acetate vehicle intramuscularly (IM) every 12h from D8 after ovulation until at least two follicles reached 33mm. At this time, ovulation was induced with 2500 IU of hCG. Artificial insemination was performed 24h after induction, and embryos were collected on the eighth day after ovulation was first detected. In Experiment 2, 112 estrous cycles in 56 mares were studied. In this experiment, the deslorelin acetate protocol was initiated only in mares that achieved a follicle with a diameter of at least 25mm and at least one second follicle with a diameter≥20mm was detected, at which time 100μg deslorelin acetate or saline was administered IM every 12h. The other procedures were similar to those described in Experiment 1. The variables studied were analyzed using Student's t-test and Fisher's exact test. In Experiment 1, only two mares in deslorelin group having second follicles of 20–25mm on responded with double ovulation. In the second experiment, 82% of treated mares responded with double ovulation, and the embryo recovery per estrous cycle was 1.12 and 0.57 in the group treated with deslorelin acetate and the control group, respectively (P<0.05). Deslorelin acetate is effective in inducing double ovulation in mares using the protocol proposed. On average, it allows for the recovery of one embryo by uterine flushing.

Comparison of 4.7-mg Deslorelin Implants and Surgery for the Treatment of Adrenocortical Disease in Ferrets

Ferrets exhibiting overt clinical signs consistent with adrenocortical disease (ACD) were separated into 2 treatment groups. One group received surgical therapy (n = 28), whereas the other group was administered a 4.7-mg deslorelin acetate implant (n = 35). Each group was evaluated for clinical response to therapy and time to return of overt disease signs. The mortality rate was calculated for the deslorelin group and for a larger pool of surgical cases (n = 54). This larger surgical group included ferrets for which follow-up to evaluate time to return of disease was not possible. The time from treatment to return of ACD signs was longer for ferrets in the deslorelin group (16.5 months) compared with the surgery group (13.6 months). Three ferrets from the surgery group showed no response to the treatment provided. All ferrets in the medical group responded to deslorelin, although the shortest period of efficacy was only 3 months for 1 ferret. Of the ferrets in the surgery group, 3 (5.5%) died within 24 hours of the procedure. No ferrets died as a direct result of implantation with deslorelin. Although there may be distinct advantages of one modality over the other for any specific patient (e.g., surgery to investigate known or suspected concurrent disease), these results suggest deslorelin is an effective and safe treatment for ACD that should be considered when surgical intervention carries significant risk.

Influence of exogenous gonadotropin-releasing hormone on seasonal reproductive behavior of the coyote ( Canis latrans)

Wild Canis species such as the coyote ( C. latrans) express a suite of reproductive traits unusual among mammals, including perennial pair-bonds and paternal care of the young. Coyotes also are monestrous, and both sexes are fertile only in winter; thus, they depend upon social and physiologic synchrony for successful reproduction. To investigate the mutability of seasonal reproduction in coyotes, we attempted to evoke an out-of-season estrus in October using one of two short-acting gonadotropin-releasing hormone (GnRH) agents: (1) a GnRH analogue, deslorelin (6- d-tryptophan-9-( N-ethyl- l-prolinamide)-10-deglycinamide), 2.1 mg pellet sc; or (2) gonadorelin, a GnRH (5-oxoPro-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-GlyNH 2) porcine hypothalamic extract, 2.0 μg/kg im once daily for 3 consecutive days. A transient increase in serum concentrations of estradiol and progesterone (1 and 2 wk, respectively) was detected after treatment with deslorelin but not gonadorelin. Also, socio-sexual behaviors reminiscent of winter mating (including courtship, mate-guarding, precoital mounts, and copulatory ties) were observed among the deslorelin group. During the subsequent breeding season (January and February), however, preovulatory courtship behavior and olfactory sampling appeared suppressed; emergence of mounts and copulations were delayed in both deslorelin and gonadorelin treatment groups. Furthermore, whereas 8 of 12 females treated in October ovulated and produced healthy litters in the spring, 4 naïve coyotes failed to copulate or become pregnant. Thus, perturbation of hormones prior to ovulation in species with complex mating behaviors may disrupt critical intrapair relationships, even if fertility is not impaired physiologically.

Comparison of the effects of eFSH and deslorelin treatment regimes on ovarian stimulation and embryo production of donor mares in early vernal transition

The objective was to compare the effects of eFSH and deslorelin treatment regimes on ovarian stimulation and embryo production of donor mares in early spring transition. Starting January 30th, mares kept under ambient light were examined by transrectal ultrasonography. When a follicle ≥25 mm was detected, mares were assigned to one of two treatment groups, using a sequential alternating treatment design. In the eFSH group, mares ( n = 18) were treated twice daily with eFSH (12.5 mg im) until they achieved a follicle ≥35 mm; hCG was given 36 h later. In the deslorelin group, mares ( n = 18) were treated twice daily with deslorelin (63 μg im) until a follicle ≥35 mm was detected, and then they were given hCG. Estrous mares were inseminated with fresh semen. Eight days after ovulation, embryo recovery attempts were performed. In each group, 14/18 (78%) mares ovulated following the eFSH or deslorelin treatment regimes. The mean (95% CI) interval from treatment initiation to ovulation was 8.2 d (7.3, 8.9) and 7.2 d (6.2, 8.1) in the eFSH and deslorelin groups, respectively. In the eFSH group, the number of ovulations was significantly higher (mean ± S.E.M.; 3.4 ± 0.4 vs. 1.1 ± 0.1 ovulations), and more embryos were recovered (2.6 ± 0.5 vs. 0.4 ± 0.2 embryos/recovery attempt). We concluded that eFSH and deslorelin treatment regimes were equally effective in inducing ovulation in early transitional mares, within a predictable time of treatment; however, the eFSH regime increased the number of ovulations and embryos recovered per mare.

The effects of surgical and chemical castration on intermale aggression, sexual behaviour and play behaviour in the male ferret ( Mustela putorius furo)

The ferret ( Mustela putorius furo) has become an increasingly popular pet animal, yet little is known about their behaviour and welfare. Inter- and intra-specific aggression and the intense musky scent are the two main reasons why male ferrets are normally surgically castrated. However, it is this neutering that is thought to play an important role in the development of hyperadrenocorticism, a hyperfunctioning of the adrenal cortex due to neoplastic changes, a common disease in domestic ferrets. An alternative to surgical castration might be the slow releasing GnRH agonist deslorelin implant (chemical castration). The present study aimed to examine the effects of the deslorelin implant and surgical castration on the occurrence of intermale aggression, sexual behaviour and play behaviour in male ferrets. Therefore, 21 male domestic ferrets received either an implant containing deslorelin ( n = 7), a placebo implant ( n = 7), or were surgically castrated ( n = 7). Our data showed that: (1) chemical castration with the GnRH agonist deslorelin results in a decrease in the occurrence of aggressive behaviour between male ferrets both in the presence and absence of a receptive female. In addition, our data showed that a deslorelin castration had more effect on the reduction of aggression than surgical castration; (2) sexually motivated behavioural patterns were reduced in the deslorelin and surgical castrated group in the male–female confrontation; (3) the deslorelin group, and to a lesser extent the surgically castrated group, had a higher incidence of play behaviour in comparison to intact males in the intermale confrontation tests. Therefore, deslorelin chemical castration is a suitable alternative for surgical castration, and may even be preferred due to the serious medical problems associated with surgical castration in ferrets. Especially the increase of play behaviour might be indicative for an improved welfare of the ferrets.

The use of a deslorelin implant (GnRH agonist) during the late embryonic period to reduce pregnancy loss

Embryonic and fetal mortality reduce reproductive performance of lactating dairy cows. The objectives of this study were to reduce pregnancy loss by administering a deslorelin implant (GnRH agonist) during the late embryonic period, to reduce follicular growth, induce accessory corpora lutea, and increase plasma progesterone concentrations. Lactating dairy cows received an implant containing 2.1 mg of deslorelin (Deslorelin group; n = 89) or no treatment (Control group; n = 92) on Day 27 of pregnancy. Pregnancy, ovarian structures and plasma progesterone concentrations were determined on Days 27 and 45, and pregnancy was re-confirmed on Day 90. On Day 45, mean ± S.E.M. numbers of class 2 (6–9 mm; 0.72 ± 0.19) and class 3 (≥10 mm; 0.86 ± 0.12) follicles for cows in the Deslorelin group were lower ( P < 0.01) than the numbers of class 2 (1.90 ± 0.18) and class 3 (1.92 ± 0.12) follicles for cows in the Control group. On Day 45, the number of accessory corpora lutea for cows in the Deslorelin group (1.80 ± 0.07) were greater ( P < 0.01) than for cows in the Control group (1.31 ± 0.07). On Day 45, plasma progesterone concentration was increased ( P < 0.01) for cows in the Deslorelin group (8.03 ± 0.33 ng/mL) compared to cows in the Control group (6.40 ± 0.31 ng/mL). Pregnancy losses did not differ between Days 27 and 45 and Days 45 and 90 for cows in the Control (15.2 and 11.0%, respectively) and Deslorelin groups (20.2 and 10.5%, respectively). However, in the Deslorelin group, pregnancy loss between Days 45 and 90 was lower ( P < 0.05) for cows that formed an accessory CL (0%) compared to cows that did not form an accessory CL (16.1%).

Influence of Deslorelin (GnRH-agonist) implant on plasma progesterone, first wave dominant follicle and pregnancy in dairy cattle

The objectives of this study were to investigate the effect of a synthetic GnRH-agonist (Deslorelin) implant on CL function and follicle dynamics when administered 48 h after PGF 2α, in a timed-insemination protocol, and to determine if the incorporation of a Deslorelin implant into a timed-insemination protocol to synchronize ovulation would be beneficial to the establishment of pregnancy. In Experiment I, 15 non lactating cyclic Holstein cows received Buserelin (8 μg, im) on Day −9, Lutalyse (25 μg, im) on Day -2, and then on Day 0 received either a Deslorelin implant (700 μg, sc; n=5), Buserelin (8 μg, im; n=5), or no treatment (control; n=5). Blood samples were collected on Days −9, −2, 0 and thereafter daily until the next ovulation. Ovaries were scanned by ultrasound on Days −9, −2, 0, 1 (day of ovulation) and 3 times a week thereafter until a subsequent ovulation. From Days 0 to 15, the rate of increase of plasma progesterone (P 4) was greater (P<0.01) for Deslorelin than for control and Buserelin. Establishment of the first-wave dominant follicle (FWDF) as a Class 3 (>9 mm) follicle was delayed (P<0.01) with Deslorelin (14.2±1.3 d) compared with the control (4.6±1.3 d) and Buserelin (5.0±1.5 d) treatments. The FWDF resumed growth after Day 13 in all 5 Deslorelin-treated cows, and 2 cows ovulated spontaneously. In 1 Deslorelintreated cow, the FWDF regressed, and a second-wave dominant follicle ovulated, while 2 other Deslorelin cows failed to ovulate until after Day 36. The cumulative numbers of Class 2 and 3 follicles was lowest in the Deslorelin group (P<0.01), while the cumulative number of Class 1 follicles was highest (Deslorelin>Buserelin>Control; P<0.01). The number of days to CL-regression and days to subsequent estrus did not differ (P>0.05) among treatments. In Experiment II, 16 lactating potentially subfertile (body condition score 2.25) cows received Cystorelin (100 μg, im; Day -9), Lutalyse (25 mg, im; Day -2), and either a Cystorelin injection (100 μg, im; n=8) or Deslorelin implant (700 μg, sc; n=8) on Day 0 and inseminated 16 h later. Deslorelin-treated cows had a higher plasma P 4 concentration between Days 0 and 16 (P<0.05) than the 2 other groups, and 5 of the 8 cows in this group were pregnant (Day 45, palpation) compared with 1 of 8 cows in the Cystorelin group (P<0.05). Incorporation of a Deslorelin implant into a timed-insemination protocol enhanced the pregnancy rate in cows of poor body condition. The results support the hypothesis that enhanced CL function and delayed establishment of the first-wave dominant follicle may enhance embryo survival.

Effect of deslorelin-induced pubertal delay on the growth of adolescents with short stature and normally timed puberty: preliminary results.

LH-releasing hormone agonist (LHRHa) treatment slows bone maturation and improves adult height in children with LHRH-dependent precocious puberty. To determine whether pubertal delay induced by LHRHa can enhance final height in patients with short stature and a normally timed puberty, we enrolled 43 short children (28 girls and 15 boys) in a double blind, placebo-controlled trial. Patients were assigned randomly to receive either placebo or LHRHa (deslorelin), administered sc at a dose of 4 micrograms/kg.day for a period of 4 yr. This report describes the preliminary results in 16 children who have completed 4 yr of treatment (9 patients in the deslorelin group and 7 patients in the placebo group). Predicted adult height increased significantly in the deslorelin-treated patients, by 7.6 cm compared to the pretreatment baseline and by 10.3 cm compared to that in the placebo-treated patients (P < 0.005). Four of the 16 patients received concurrent GH treatment (3 among the deslorelin-treated patients and 1 among the placebo-treated patients). Omitting these patients from the analysis did not materially affect the results: predicted adult height in the deslorelin-treated patients increased by 7.2 cm compared to the pretreatment baseline and by 10.9 cm compared to that in the placebo-treated patients (P < 0.005). We conclude that pubertal delay induced by deslorelin significantly increases predicted adult height in adolescents with short stature and a normally timed puberty. Whether deslorelin treatment will increase the final height of these patients cannot be determined until they have stopped growing.

Gonadotropin-releasing hormone

The aim of this study was to verify the effect of deslorelin and sulpiride association on double ovulation induction in mares. Ten mares were used for this study. Eight days after ovulation, luteolysis was induced and mares were submitted a daily ultrasonographic evaluation until observation of at least two follicles measuring between 20 and 25 mm. Animals were split in two experimental groups in a crossover study. In deslorelin (DES) group, the animals received 150 μg deslorelin, intramuscularly, every 12 hours, until the second largest follicle reached at least 33 mm in diameter, at which time ovulation induction was performed with 1.500 IU of human chorionic gonadotrophin, IV. In the DES + sulpiride (SULP) group, the treatment was performed in the same manner as in the DES group, associated with the administration of 1 g of sulpiride, orally, once daily until the time of ovulations induction. In both groups, ultrasound examinations were performed daily to evaluate follicular development and the detection of ovulations. Double ovulations were observed in 70% (7/10) of the animals of the DES group and 50% (5/10) of the animals in the DES + SULP group. The percentage of ovulations corresponding to the number of follicles developed was 81.8% (18/22) for the DES group and 79% (15/19) for the DES + SULP group, and no difference was observed between the groups (P > .05). We conclude that association of sulpiride with deslorelin acetate did not contribute to the increase in double ovulations in mares.