Evaluation of the effects of GNRH use on reproductive performance in Clarias gariepinus using meta-analysis method

Gonadotropin releasing hormone (GnRH) is a key endocrine secretion that regulates reproductive functions in animals. The secretion of this hormone is crucial for follicular development and ovulation. It is commonly used to enhance fertility in animals, induce ovulation, and treat ovarian cysts. GnRH achieves these effects by stimulating the secretion of follicle-stimulating hormone and luteinizing hormone. This thesis examines the use of GnRH in the Clarias gariepinus, aiming to increase fertilization rates, improve hatching success, shorten the time to ovulation, and enhance the survival rates of offspring. A meta-analysis approach was employed to evaluate these effects. For this purpose, a comprehensive literature review was conducted using databases such as PubMed, Web of Science, ScienceDirect, Scopus, and Google Scholar, following the PRISMA method. Studies identified through this search were subjected to a selection process, including title and abstract screening, followed by full-text analysis. Data from the selected studies were extracted, including the first author's name, date, population, study type, treatment, outcome variables, sample sizes, and mean and standard deviation values for both experimental and control groups. The data were analyzed using both the Random Effects Model (REM) and Fixed Effects Model (FEM) to determine effect sizes, utilizing the Meta-Essentials program. Results demonstrated that GnRH administration in female Clarias gariepinus effectively reduced the time to ovulation, increased fertilization rates, and improved the survival rates, suggesting GnRH as a viable method to stimulate reproduction in fish. As a result, it was concluded that GnRH can be used to stimulate reproduction in female fish.