The Effect of Melatonin Supplementation During In Vitro Maturation of Sheep Oocytes on Heat Stress and Embryo Development

Ahmet Aktar; Selim Alçay

Article Details

The Effect of Melatonin Supplementation During In Vitro Maturation of Sheep Oocytes on Heat Stress and Embryo Development

Authors:

Ahmet Aktar | Selim Alçay

Publisher:

Bursa Uludağ University

Main Topics:

Veterinary Sciences (Other)

Journal:

Journal of Research in Veterinary Medicine Vol.44 Issue 1, pp.42-48

Document Type:

Article

Publication Date:

7/2025

Document Language:

Turkish

Document ID (Org No.):

2001355594

pISSN:

2667-6745

Keywords:

Abstract:

 The aim of this study was to investigate the effect of melatonin administration during in vitro oocyte maturation in sheep on heat stress, with a focus on its impact at the level of embryonic development. One of the most critical stages in in vitro embryo IVF production is the oocyte maturation phase, during which the maturation rate of oocytes plays a key role. Stress factors encountered during this stage lead to an increase in reactive oxygen species, causing cellular damage. This study evaluated the embryonic development of sheep oocytes exposed to heat stress and treated with the hormone melatonin. A concentration of 10⁷ M melatonin was added to the maturation medium under different temperature conditions. Oocytes were collected from the ovaries of sheep slaughtered at a local abattoir. Incubation procedures were carried out using specially prepared solutions under appropriate laboratory conditions. Embryonic development was assessed through cleavage, morula, and blastocyst stages. When cleavage rates were compared, the highest rate was observed in group G39M, and the lowest in group G41, with a statistically significant difference P0.05. Similarly, the highest morula rate was found in G39M, while the lowest was in G41 P0.05. The best blastocyst rates were also observed in G39M. Accordingly, melatonin showed a positive effect on cleavage and morula stages under heat stress; however, a significant reduction was observed at the blastocyst stage P0.05.

 The aim of this study was to investigate the effect of melatonin administration during in vitro oocyte maturation in sheep on heat stress, with a focus on its impact at the level of embryonic development. One of the most critical stages in in vitro embryo IVF production is the oocyte maturation phase, during which the maturation rate of oocytes plays a key role. Stress factors encountered during this stage lead to an increase in reactive oxygen species, causing cellular damage. This study evaluated the embryonic development of sheep oocytes exposed to heat stress and treated with the hormone melatonin. A concentration of 10⁷ M melatonin was added to the maturation medium under different temperature conditions. Oocytes were collected from the ovaries of sheep slaughtered at a local abattoir. Incubation procedures were carried out using specially prepared solutions under appropriate laboratory conditions. Embryonic development was assessed through cleavage, morula, and blastocyst stages. When cleavage rates were compared, the highest rate was observed in group G39M, and the lowest in group G41, with a statistically significant difference P0.05. Similarly, the highest morula rate was found in G39M, while the lowest was in G41 P0.05. The best blastocyst rates were also observed in G39M. Accordingly, melatonin showed a positive effect on cleavage and morula stages under heat stress; however, a significant reduction was observed at the blastocyst stage P0.05.

 The aim of this study was to investigate the effect of melatonin administration during in vitro oocyte maturation in sheep on heat stress, with a focus on its impact at the level of embryonic development. One of the most critical stages in in vitro embryo IVF production is the oocyte maturation phase, during which the maturation rate of oocytes plays a key role. Stress factors encountered during this stage lead to an increase in reactive oxygen species, causing cellular damage. This study evaluated the embryonic development of sheep oocytes exposed to heat stress and treated with the hormone melatonin. A concentration of 10⁷ M melatonin was added to the maturation medium under different temperature conditions. Oocytes were collected from the ovaries of sheep slaughtered at a local abattoir. Incubation procedures were carried out using specially prepared solutions under appropriate laboratory conditions. Embryonic development was assessed through cleavage, morula, and blastocyst stages. When cleavage rates were compared, the highest rate was observed in group G39M, and the lowest in group G41, with a statistically significant difference P0.05. Similarly, the highest morula rate was found in G39M, while the lowest was in G41 P0.05. The best blastocyst rates were also observed in G39M. Accordingly, melatonin showed a positive effect on cleavage and morula stages under heat stress; however, a significant reduction was observed at the blastocyst stage P0.05.

 Çalışmada koyunlarda in vitro maturasyon sırasında uygulanan melatonin hormonunun sıcaklık stresi üzerine etkisinin embriyonik gelişim düzeyinde araştırılması amaçlanmıştır. In vitro embriyo IVF üretim aşamlarından en kritik noktalardan birisi de in vitro maturasyon aşamasında oositlerin mature olma oranlarıdır. Bu aşamada meydana gelen streslere bağlı olarak reaktif oksijenlerin artması hücrelerde hasarlara sebep olmaktadır. Melatonin hormonunun sıcaklık stresine karşı koyun oositlerinde meydana gelen embriyonik gelişim değerlendirildi. Maturasyon medyumu içerisine farklı sıcaklıklarda 10-7 M melatonin hormunu ilave edildi. Mezbahada kesilen koyunların ovaryumlarından oositler elde edildi. Uygun şartlar altında laboratuvar ortamında hazırlanan solüsyonlar ile inkübasyon işlemleri gerçekleştirildi. Embriyonik gelişim aşamaları bölünme, marula, blastosit aşamaları olarak değerlendirildi. Bölünme oranları kıyaslandığında en yüksek oran G39M, en düşük değer G41 elde edildi ve istatiksel olarak anlamlı bir fark vardır P0,05. Morula oranlarında ise en yüksek değer G39M gözlenirken en düşük değer G41 elde edildi P0,05. Elde edilen blastosist oranları en iyi G39M de elde edildi. Buna göre melatonin sıcaklık stresinde bölünme ve marula aşamasında etki gösterirken blastosit aşamasında anlamlı ölçüde azalma oldu. P0,05.

Article Details

The Effect of Melatonin Supplementation During In Vitro Maturation of Sheep Oocytes on Heat Stress and Embryo Development

Authors:

Ahmet Aktar | Selim Alçay

Publisher:

Bursa Uludağ University

Main Topics:

Veterinary Sciences (Other)

Journal:

Journal of Research in Veterinary Medicine Vol.44 Issue 1, pp.42-48

Document Type:

Article

Publication Date:

7/2025

Document Language:

Turkish

Document ID (Org No.):

2001355594

pISSN:

2667-6745

IVF

Melatonin

Heat Stress

Embryonic DevelopmentIVF

Melatonin

Sıcaklık Stresi

Embriyonik Gelişim

Issues

Article Details

Authors: Ahmet Aktar | Selim Alçay

Publisher: Bursa Uludağ University

Main Topics: Veterinary Sciences (Other)

Journal: Journal of Research in Veterinary Medicine Vol.44 Issue 1, pp.42-48

Document Type: Article

Publication Date: 7/2025

Document Language: Turkish

Document ID (Org No.): 2001355594

pISSN: 2667-6745

Issues

Authors:

Ahmet Aktar | Selim Alçay

Publisher:

Bursa Uludağ University

Main Topics:

Veterinary Sciences (Other)

Journal:

Journal of Research in Veterinary Medicine Vol.44 Issue 1, pp.42-48

Document Type:

Article

Publication Date:

7/2025

Document Language:

Turkish

Document ID (Org No.):

2001355594

pISSN:

2667-6745