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Vertebrate reproductive science and technology
RESEARCH ARTICLE

Beneficial effects of melatonin on in vitro embryo production from juvenile goat oocytes

Sandra Soto-Heras A , Montserrat Roura A , Maria G. Catalá A , Irene Menéndez-Blanco A , Dolors Izquierdo A , Ali A. Fouladi-Nashta B and Maria T. Paramio A C
+ Author Affiliations
- Author Affiliations

A Departament de Ciència Animal i dels Aliments, Facultat de Veterinària, Universitat Autònoma de Barcelona, Travessera dels Turons s/n, 08193 Bellaterra, Barcelona, Spain.

B Reproduction Genes and Development Group, Department of Veterinary Basic Sciences, The Royal Veterinary College, Hawkshead Lane, Hatfield, Herts AL97TA, UK.

C Corresponding author. Email: teresa.paramio@uab.cat

Reproduction, Fertility and Development 30(2) 253-261 https://doi.org/10.1071/RD17170
Submitted: 25 January 2017  Accepted: 31 May 2017   Published: 19 June 2017

Abstract

Melatonin is a universal antioxidant that improves in vitro embryo production in several species. The aims of this study were to determine the melatonin concentration in the ovarian follicular fluid (FF) of juvenile goats and the effect of melatonin during in vitro maturation (IVM) on embryo development. The FF melatonin concentration was 0.57­–1.07 × 10−9 M, increasing with follicular diameter. Oocytes were matured, fertilised and cultured under conventional conditions. Blastocyst development, embryo quality and levels of reactive oxygen species (ROS) and reduced glutathione were assessed. In Experiment 1 different melatonin concentrations (10−3, 10−7, 10−9, 10−11 M) were added to the IVM medium, which contained cysteamine as antioxidant, and no differences were observed. In Experiment 2, melatonin (10−7 M) was tested in the presence or absence of cysteamine (experimental groups: melatonin, cysteamine, melatonin + cysteamine, non-antioxidant). The melatonin group presented a higher blastocyst rate than the non-antioxidant group (28.9 vs 11.7%; P < 0.01) and a higher total cell number than the cysteamine group (225.1 vs 129.0; P < 0.05). Oocytes from the melatonin and cysteamine groups had lower ROS levels than those from the non-antioxidant group. This study shows that melatonin is an interesting tool for improving oocyte competence in juvenile goats as it increases embryo production and quality.

Additional keywords: cysteamine, embryo development, in vitro maturation, oocyte competence, reactive oxygen species.


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