Contraception is increasingly used to manage breeding opportunities in conservation-dependent species. This study aimed to determine the efficacy, duration of effect, optimal dose and potential side effects of Suprelorin contraceptive implants in Tasmanian devils, for use in the conservation breeding program. In our pilot study, Suprelorin was found to effectively suppress oestrous cycles in female devils, yet caused a paradoxical increase in testosterone in males. Therefore, we focussed on females in further trials. Females received one (n=5), two (n=5) or no (n=5) Suprelorin implants, with quarterly gonadotrophin-releasing hormone (GnRH) challenges used to test pituitary responsiveness over two breeding seasons. Both Suprelorin doses suppressed pituitary responsiveness for at least one breeding season, with a reduced effect in the second. There was a dose-response effect on duration rather than magnitude of effect, with high-dose devils remaining suppressed for longer than low-dose animals. There were no apparent negative effects on general health, yet captivity and contraception together may cause weight gain. Suprelorin contraceptive implants are now routinely used in the Save the Tasmanian Devil Program insurance metapopulation to meet the aims of maintaining genetic and behavioural integrity by controlling individual reproductive contributions in group housing situations.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1071/RD18407 | DOI Listing |
Pharmaceuticals (Basel)
December 2024
College of Pharmacy, University of Illinois, Chicago, IL 60612, USA.
Overexpression of the gonadotropin-releasing hormone receptor (GnRH-R) plays a vital role in the advancement of reproductive malignancies such as ovarian, endometrial, and prostate cancer. Peptidomimetic GnRH antagonists are a substantial therapeutic development, providing fast and reversible suppression of gonadotropins by directly blocking GnRH-R. Unlike typical GnRH agonists, these antagonists prevent the early hormonal flare, have a faster onset of action, and have a lower risk of cardiovascular problems.
View Article and Find Full Text PDFAnimals (Basel)
January 2025
School of Agriculture and Biology, Liaocheng University, Liaocheng 252059, China.
and miRNA regulate mammalian pubertal initiation and Gonadotropin-releasing hormone (GnRH) production. However, it remains unclear which signaling pathways regulates to modulate GnRH production. In this study, the mRNA expression levels of and in the pubertal and juvenile goat hypothalamus and pituitary gland were detected, and expression in the pubertal hypothalamus decreased significantly compared with that in juvenile tissues.
View Article and Find Full Text PDFBMC Pediatr
January 2025
Department of Endocrinology, Genetics and Metabolism, Fuzhou First General Hospital Affiliated with Fujian Medical University, Fuzhou Children's Hospital of Fujian Medical University, Fuzhou, 350005, China.
Objective: In boys during puberty who were undergoing recombinant human growth hormone (rhGH) treatment, we compared the therapeutic efficacy on growth, and any adverse reactions, of co-therapy with either letrozole or gonadotropin-releasing hormone analog (GnRHa).
Methods: Fifty-six pubertal growth hormone deficiency (GHD) boys were studied, they were treated with the combination of letrozole and rhGH (letrozole group, n = 28) or the combination of GnRHa and rhGH (GnRHa group, n = 28) for at least one year. Eighteen patients in the letrozole group and seventeen patients in the GnRHa group attained final adult height (FAH).
Physiol Behav
January 2025
University of Northern Parana (UNOPAR), Londrina, PR, Brazil.. Electronic address:
Undernutrition has increased worldwide in recent years and it is known that environmental factors to which individuals are exposed in early life can result in metabolic and reproductive changes that remain in adult life. In this context, the litter size expansion is a classic model used to induce undernutrition early in development. Thus, this study aimed to evaluate the effects of neonatal undernutrition induced by the litter size expansion on metabolic and reproductive parameters of female rats.
View Article and Find Full Text PDFMedicine (Baltimore)
January 2025
Department of Internal Medicine, Division of Hematology and Oncology, Jeonbuk National University Hospital, Jeonbuk National University Medical School, Jeonju, Republic of Korea.
Rationale: Aggressive angiomyxoma (AAM) is an exceptionally rare mesenchymal tumor that predominantly manifests in the female genital organs during the reproductive age. Its rarity alone makes it a fascinating subject for study. The diagnosis of AAM necessitates differentiation from other benign or mesenchymal tumors and can be confirmed through immunohistochemistry (IHC) staining.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!