Establishment of a low-level laser irradiation protocol for in vitro development of bovine embryos

Plavšić, Aleksandar (author), Zorc, Minja (author), Dovč, Peter (author)

Photobiomodulation using low-level laser irradiation has been proposed as a non-thermal approach for stimulating cellular metabolism, but practical protocols for its application to bovine embryos after fertilisation remain insufficiently described. This study aimed to establish a practical low-level laser irradiation procedure at different time points during the in vitro development of bovine embryos. Abattoir-derived oocytes were matured, fertilised with semen from a single bull, and cultured under standard conditions. Entire culture dishes were irradiated using a K-Laser Cube at 800 nm and 0.10 W for 200 s, delivering 20 J, on day one, three or five after fertilisation; an untreated run served as a reference. Embryos were evaluated on day seven according to International Embryo Transfer Society standards. Across four separate production runs, 1345 inseminated oocytes yielded 348 blastocysts meeting IETS stage 6, quality grade 1 criteria (26% overall); blastocyst rates were 27.8%, 22.0%, 25.9% and 28.5% for the reference, day one, day three and day five runs. Because each treatment was tested in a separate run, these values are descriptive and do not permit assessment of treatment efficacy. The procedure was incorporated into routine bovine in vitro embryo production and provides a basis for future validation studies.

• Language: English
• Keywords: cattle, in vitro embryo production, photobiomodulation, low-level laser, blastocyst rate, embryo transfer
• Work type: Article
• Typology: 1.03 - Other scientific articles
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: 8 str.
• Numbering: Vol. 13, issue 9, [article no.] 913
• PID: 20.500.12556/RUL-186917
• UDC: 636.2
• ISSN on article: 2306-7381
• DOI: 10.3390/vetsci13090913
• COBISS.SI-ID: 290164995
• Publication date in RUL: 07.09.2026

Record is a part of a journal

• Title: Veterinary sciences
• Shortened title: Vet. sci.
• Publisher: MDPI AG
• ISSN: 2306-7381
• COBISS.SI-ID: 523429657

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: govedo, embriotransfer, razvoj zarodkov, lasersko obsevanje

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P4-0220
• Name: Primerjalna genomika in genomska biodiverziteta