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Effect of GnRH agonist (deslorelin) on reproductive activity in captive female veiled chameleons ().Veterinarni Medicina Jul 2023Eighteen 5 months old veiled chameleon females () were used in the study. Seven females received subcutaneous implants with gonadotropin-releasing hormone agonist...
Eighteen 5 months old veiled chameleon females () were used in the study. Seven females received subcutaneous implants with gonadotropin-releasing hormone agonist (GnRH) deslorelin acetate whereas eleven females were used as control animals without any implants. Females were kept in five terraria, in groups of four females (in 3 terraria) and groups of three females (in 2 terraria), respectively. A minimum of one female with GnRH implants was present in each terrarium. They were kept under standard husbandry conditions. Females of both groups (females with GnRH and controls, respectively) were monitored for three years. No differences between females with GnRH implants and females without GnRH implants were observed with respect to the presence of large ovarian follicles, number of eggs/female, or number of clutches/female. GnRH implants did not prevent spontaneous reproductive activity in any of the 7 females with implants. Ovariectomy was performed in 8 females (4 females with GnRH implants and 4 control females). Ten females (3 females with GnRH implants and 7 control females) had to be euthanised. In 17 of 18 female veiled chameleons of this study histologic examination revealed heterophilic granulomatous oophoritis. The use of GnRH agonist implants did not prove to be an appropriate method for the control of reproductive function in captive female veiled chameleons.
PubMed: 37982053
DOI: 10.17221/31/2023-VETMED -
Journal of the American Association For... Nov 2023Hormonal contraception is an effective, reversible tool for managing birth rates in humans and nonhuman animals alike. However, manipulating reproductive hormones has...
Hormonal contraception is an effective, reversible tool for managing birth rates in humans and nonhuman animals alike. However, manipulating reproductive hormones has behavioral consequences that can impact social and sexual behavior between conspecifics. First, we studied 18 pairs of nonreproductive titi monkeys () to test the efficacy of a novel method of hormonal contraception (deslorelin acetate implants) on reproductive hormone cycling in females and found significant reductions in urinary estrogens and progestagens among treated females compared to untreated controls. We then studied 35 nonreproductive pairs of coppery titi monkeys () to ascertain whether treating females with one of 2 different forms of hormonal contraception (deslorelin acetate implants ( = 17) or medroxyprogesterone acetate injections ( = 9)) would influence the relationship between pair mates compared to the relationship between untreated females and their vasectomized male mates ( = 9). Over a 5-month period, we found no differences in affiliative behaviors between pairs containing untreated females compared to pairs in which the female was treated with either deslorelin acetate or medroxyprogesterone acetate. Similarly, we found no differences in affiliation between pairs in the 2 treatment groups. This study is the first to examine behavioral consequences of hormonal contraception in a pair-bonding species. The results are encouraging for captive, managed breeding colonies of such social animals, especially those used in behavioral research.
Topics: Humans; Male; Female; Animals; Contraceptive Agents; Callicebus; Medroxyprogesterone Acetate; Social Behavior
PubMed: 37973152
DOI: 10.30802/AALAS-JAALAS-23-000017 -
JFMS Open Reports 2023The aim of this clinical case presentation was to describe the effect of a 4.7 mg deslorelin implant placement in a pregnant queen during the second half of gestation,...
CASE SUMMARY
The aim of this clinical case presentation was to describe the effect of a 4.7 mg deslorelin implant placement in a pregnant queen during the second half of gestation, and the consequences of its removal on the pregnancy and parturition. A 5-year-old female cat exhibiting nesting behaviour and weight gain 10 days after placement of a deslorelin implant was presented for examination. Gestation was confirmed on ultrasound, with two well-formed kittens of a gestational age of approximately 7 weeks. The deslorelin implant placed on the umbilicus was removed 1 week later. No change in the pregnancy was observed after removal of the implant. The fetuses showed no signs of distress on ultrasound and radiography examination 4 days after removal of the implant. One week after implant removal, the queen naturally delivered two healthy kittens. The queen showed maternal behaviour with normal milk production.
RELEVANCE AND NOVEL INFORMATION
In the light of the lack of literature on implant injection and removal in the pregnant queen, this case report showcases a successful birth of healthy kittens without any subsequent adverse effect on the queen. Further study is needed to assess the safety of implant removal during pregnancy and potential use as a means to induce fertile oestrus in the queen.
PubMed: 37873522
DOI: 10.1177/20551169231201606 -
Journal of the American Association For... Nov 2023Sterility in male NHP has long been achieved through surgical castration or vasectomy. However, these techniques are irreversible, require a surgical procedure, and have...
Sterility in male NHP has long been achieved through surgical castration or vasectomy. However, these techniques are irreversible, require a surgical procedure, and have potential consequences such as sperm granulomas and long recovery time. Deslorelin is a gonadotropin-releasing hormone agonist that temporarily and reversibly suppresses sex hormone secretion. Our goal in this study was to investigate the effects of deslorelin on testosterone secretion and testicular volume in male rhesus macaques (). Male macaques ( = 4) each received two, 4.7-mg deslorelin implants subcutaneously in the interscapular region. Serum testosterone and testicular volume were then monitored at specific time points until 10 mo after treatment. Testosterone suppression was defined as testosterone levels lower than 0.6 ng/mL for a sustained period of at least 30 d. After implantation, mean testicular volume was significantly reduced by day 121. Testosterone suppression was observed in all subjects. However, the time from implantation to testosterone suppression and duration of suppression varied. Two macaques were hormonally suppressed by day 26 after implantation and remained suppressed for at least 6 mo. The other 2 macaques were hormonally suppressed by 2 mo after implantation; of these two, one remained suppressed for 70 days while the other was suppressed for at least 245 days. We conclude that deslorelin can safely suppress testosterone secretion in male rhesus macaques, but individual variation in onset and duration of action should be considered when establishing reimplantation time points and potential return to reproductive activity.
Topics: Male; Animals; Testis; Gonadotropin-Releasing Hormone; Macaca mulatta; Testosterone; Semen; Drug Implants; Triptorelin Pamoate
PubMed: 37844997
DOI: 10.30802/AALAS-JAALAS-22-000116 -
Animals : An Open Access Journal From... Aug 2023Deslorelin implant use in cats is a medical alternative to surgical sterilization, and due to its prolonged efficacy, its use has shown growing interest in the...
Deslorelin implant use in cats is a medical alternative to surgical sterilization, and due to its prolonged efficacy, its use has shown growing interest in the veterinary community. In the case of breeding facilities, its removal is often requested for the early restoration of testicular function. As anti-Müllerian hormones (AMH) in males is dependent of testosterone secretion, its assay may determine the restoration of testicular steroid secretion. An average of 3 weeks has been already described for tomcats' testicular function resumption after implant removal, but information about AMH concentrations in deslorelin-treated tomcats is lacking. Fourteen tomcats were treated for temporary suppression of fertility with a 4.7 mg deslorelin implant, which was surgically removed after 3, 6 or 9 months (n = 6, 4 and 4 tomcats, respectively). A general clinical and reproductive check with a gonadorelin stimulation test for testosterone determination was performed before deslorelin implant administration. After implant removal, tomcats' testicles were ultrasonographically checked for volume determination every 1-2 weeks with observation of the glans penis (presence or absence of spikes) and blood collection to assay both testosterone and AMH concentrations. AMH concentrations increased significantly during the deslorelin treatment from 20.95 ± 4.97 ng/mL to 82.41 ± 14.59 ng/mL ( < 0.05). Following implant removal, AMH concentrations progressively decreased to pre-treatment levels, with a value of 28.42 ± 7.98 ng/mL on the third week post-removal where testosterone secretion was again detected. Even if a big variability of AMH concentrations exists between male individuals, resumption of tomcats' testicular function following a deslorelin treatment can be determined by AMH assay.
PubMed: 37627341
DOI: 10.3390/ani13162552 -
Veterinary Research Communications Dec 2023Deslorelin acetate is a gonadotropin-releasing hormone agonist formulated in a controlled-release subcutaneous implant and designed for reversible suppression of...
Effect of a subcutaneous implant of deslorelin acetate on serum testosterone concentrations in male Hermann's (Testudo hermanni sp.) and Greek (Testudo graeca sp.) tortoises.
Deslorelin acetate is a gonadotropin-releasing hormone agonist formulated in a controlled-release subcutaneous implant and designed for reversible suppression of testosterone production in dogs. It has also been demonstrated to be effective in other animal species, but no data on its effectiveness in male land tortoises are available. This study aimed to evaluate the effect of a 4.7-mg deslorelin acetate implant on serum testosterone concentrations in male Hermann's (Testudo hermanni sp.) and Greek (Testudo graeca sp.) tortoises. Twenty adult male tortoises housed under the same environmental conditions were enrolled for the study and randomly assigned to a treatment (D, n = 10) or a control (C, n = 10) group. Starting in May, males from the D group were implanted with a 4.7-mg deslorelin acetate device, whereas males from the C group did not receive any treatment. Blood samples were collected once immediately before implant application (S0-May) and at 15 days (S1-June), 2 (S2-July), and 5 (S3-October) months after application. Serum testosterone at each sampling time was measured through a solid-phase, enzyme-labeled, competitive chemiluminescent immunoassay. Median serum testosterone concentrations were not significantly different between the two groups in all sampling times, and no interaction between treatment and sampling time was observed. The present study, therefore, suggests that a single treatment with a 4.7-mg deslorelin acetate implant has no effect on testosterone circulation in male Hermann's and Greek tortoises during the following 5 months.
Topics: Animals; Male; Dogs; Turtles; Greece
PubMed: 37173553
DOI: 10.1007/s11259-023-10138-6 -
Journal of Feline Medicine and Surgery May 2023There has been a growing interest in alternatives to surgery for controlling reproduction in tom cats, and the resultant medical options add to a practitioner's toolbox... (Review)
Review
BACKGROUND
There has been a growing interest in alternatives to surgery for controlling reproduction in tom cats, and the resultant medical options add to a practitioner's toolbox when handling these cases in clinical practice. It is important, however, that when suggesting these drugs, veterinarians have a good understanding of their mode of action, and their correct use and dosage.
CLINICAL RELEVANCE
Breeders increasingly wish to be able to switch on/off the reproductive ability of their tom cats in a controlled manner. In addition, in small animal medicine, there has been concern from some academics, and a growing number of pet cat owners, about potential long-term effects of surgical sterilisation. Further, for some cats surgical castration may not be possible due to health conditions that mean anaesthesia is unsafe. In all of these scenarios, medical alternatives to surgery can prove useful.
EQUIPMENT AND TECHNICAL SKILLS
No special equipment or technical skills are required. A good knowledge of the medical alternatives to surgical sterilisation for controlling reproduction in a tom, and making sure the patient is a suitable candidate, are, however, important for ensuring the cat's health during and after treatment and the owner's satisfaction.
AUDIENCE
This review is aimed principally (but not exclusively) at veterinary practitioners working with cat breeders who seek a temporary arrest in their tom cat's reproduction. It may also help practitioners with clients who would like an alternative to surgery or with cats where anaesthesia for surgical castration is not possible.
EVIDENCE BASE
Advances in reproductive feline medicine have resulted in improved knowledge of medical contraception. This review draws on scientific evidence-based papers that report on the mode of action, length of efficacy and potential side effects of different methods of medical contraception, as well as the authors' own clinical experience.
Topics: Cats; Animals; Libido; Reproduction; Fertility; Contraception; Castration
PubMed: 37158289
DOI: 10.1177/1098612X231171406 -
Animals : An Open Access Journal From... Jan 2023This multicenter-controlled, double-masked randomized European study was conduc-ted to confirm both the efficacy and safety of a deslorelin implant in controlling...
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 ( < 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).
PubMed: 36766268
DOI: 10.3390/ani13030379 -
Animals : An Open Access Journal From... Jan 2023Deslorelin is currently registered for the induction of temporary infertility in male dogs, male cats, male ferrets, and also prepubertal female dogs, but research has...
Deslorelin is currently registered for the induction of temporary infertility in male dogs, male cats, male ferrets, and also prepubertal female dogs, but research has shown its usefulness for other conditions requiring chronic treatment. This paper presents six cases of dogs chronically treated with deslorelin for indications such as benign prostatic hyperplasia, control of fertility, abnormal reproductive behavior and urinary incontinence. All animals were in good health during treatment. Treatment duration was 2-9 years. No short-term side effects were observed except for flare-up reactions, which were observed only in 1/4 intact males. Two dogs developed a neoplasia: a spayed bitch treated for urinary incontinence developed a pituitary carcinoma, and an intact male dog implanted for control of fertility developed a bladder carcinoma. While the pituitary carcinoma seems unlikely to be related to deslorelin, the bladder carcinoma could be due to the neutered condition of the dog (which was treated for 9 years) as urinary tract neoplasia is more common in dogs following gonadectomy. Chronic treatment with deslorelin is regarded as safe when an animal is being treated for life. The possibility that a pause in the treatment might be helpful for the animal should be investigated.
PubMed: 36670804
DOI: 10.3390/ani13020265 -
Animals : An Open Access Journal From... Jan 2023This study was performed to monitor estrous patterns and, more importantly, changes in anti-Müllerian hormone (AMH) concentrations during the peri-ovulatory period in...
This study was performed to monitor estrous patterns and, more importantly, changes in anti-Müllerian hormone (AMH) concentrations during the peri-ovulatory period in deslorelin-induced estrous bitches. Healthy anestrous bitches (n = 4) were used. Estrus and ovulation were monitored after deslorelin implantation. Blood samples were collected for analysis of progesterone, estradiol-17ß and AMH concentrations before implantation (day 0) and on days 6, 8, 10, 12, 14, 16, 18, 20 and 22 after implantation. Six days following treatment, all bitches showed estrus signs. Ovulation took place between days 12 and 15. Circulating AMH concentrations varied among bitches from 0.12 to 3.08 ng/mL. However, no significant differences in AMH levels (mean ± SD) were observed between day 0 and days following post-implantation (p > 0.05). There were no significant correlations between AMH and estradiol or AMH and progesterone (p > 0.05). Ultrasonographically, the number of clearly identifiable ovarian follicles was higher before ovulation and the area of ovaries increased after ovulation (p < 0.05). Except for AMH, changes in vaginal cytology, estradiol-17ß and progesterone levels observed in our study were similar to naturally occurring estrus. Large intra- and inter-individual variation in AMH were observed suggesting that AMH is currently not suitable as a canine fertility marker to monitor ovarian response to deslorelin treatment for estrus induction.
PubMed: 36670799
DOI: 10.3390/ani13020258