From spermatogenesis to fertilisation: the role of melatonin on ram spermatozoa.

This review presents recent findings on the effect of melatonin on ram spermatozoa. This hormone regulates seasonal reproduction in the ovine species through the hypothalamic-pituitary-gonadal axis, but it also exerts direct effects on spermatogenesis, seminal quality and fertility. In the testis, melatonin stimulates blood flow to this organ, but it also appears to be involved in the differentiation of spermatogonial stem cells and the secretion of testosterone through the MT1 and MT2 receptors.

Melatonin in Male Dromedary Camel () Seminal Plasma and Its Specific MT1 and MT2 Receptors on Sperm Membranes.

Camels () are seasonal short-day breeders, regulated by photoperiod and melatonin secretion. However, no studies have explored melatonin levels in camel seminal plasma or their relationship with testosterone, age, or climatic factors, nor is it known whether melatonin receptors exist in camel spermatozoa to respond to seminal melatonin. This study aimed to analyze melatonin levels in camel seminal plasma and its specific receptors in spermatozoa.

Differential effect of melatonin on ram spermatozoa depending on the allelic variant of the polymorphism of the gene, incubation medium and season.

Context The Rsa I polymorphism of the melatonin receptor MTNR1A gene affects seasonal reproduction in sheep, but its effect on ram spermatozoa and their response to melatonin is unknown. Aims This study aims to evaluate whether Rsa I polymorphism of the MTNR1A gene influences the response of ram spermatozoa to in vitro added melatonin. Methods Spermatozoa from rams carrying different Rsa I allelic variants were incubated with melatonin in a TALP medium or a capacitation-triggering medium during the reproductive and non-reproductive seasons.

Genotyping of rams based on melatonin receptor 1A gene polymorphisms: a tool in sire selection?

Context Several polymorphisms in the melatonin receptor 1A gene (MTNR1A ) have been related to reproductive performance in ovine. Aims To investigate the effect of the Rsa I and Mnl I polymorphisms on ram seminal quality. Methods Eighteen Rasa Aragonesa rams were genotyped for the Rsa I (C/C, C/T, T/T) and Mnl I (G/G, G/A, A/A) allelic variants of the MTNR1A gene.

Proximate analysis and GC-MS phytochemical profiling of aqueous extracts of , a plant used by the Mbya-Guaraní as a contraceptive.

(Presl) Fée, a traditional contraceptive in Mbya culture, lacks scientific scrutiny regarding its chemical composition and contraceptive efficacy. Employing X-ray fluorescence, Fourier-transform infrared spectroscopy, and thermal analysis, we explored the plant's organs. Multielemental analysis excluded toxic elements.