Review Article
Novelties in ovine artificial insemination – A review
Toni Dovenski*,
Plamen Trojacanec,
Branko Atanasov,
Martin Nikolovski,
Vladimir Petkov,
Florina Popovska-Percinic,
Monika Dovenska,
Juraj Grizelj,
Silvijo Vince

Mac Vet Rev 2022; 45 (2): i - xvii


Received: 20 September 2021

Received in revised form: 01 March 2022

Accepted: 05 March 2022

Available Online First: 04 April 2022

Published on: 15 October 2022

Correspondence: Toni Dovenski,


Artificial insemination (AI) as a part of assisted reproductive technologies represents the oldest and most widespread method used to accelerate genetic progress in all domestic animals. After its first implementation in ovine reproduction and almost 80 years afterward, AI is continuously used for improving the genetic merit, utilizing either fresh or shorttime chilled semen. Nevertheless, regardless of the semen used for insemination, the conception rate (CR) is still lower in comparison to natural service. At least two factors are commonly thought to limit the success of the AI and reduce the CR: (1) failure of placing the semen directly into the uterus due to the specific anatomic structure of the ewe’s cervix; (2) lower viability of ram spermatozoa during cryopreservation (<30% progressively motile spermatozoa after thawing). This review elaborates on recent studies that aimed to achieve acceptable CR through the implementation of cervical or intrauterine insemination: deep intracervical, intrauterine trans-cervical, and intracornual. Several hormonal treatments (oxytocin, estrogen, or prostaglandin) were evaluated on inducing cervical dilation that facilitates insemination. A comprehensive analysis was given to the effects of several antioxidants (GSSG, GSH, and cysteine) supplemented in ram semen-freezing media. Sex-sorted ram semen fertility rate results were presented from our studies.

Keywords: artificial insemination, sheep, insemination, ejaculate conservation, sex sorted semen


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© 2022 Dovenski T. This is an open-access article published under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Conflict of Interest Statement

The authors have declared that no competing interests exist.

Citation Information

Macedonian Veterinary Review. Volume 45, Issue 2, Pages i-xvii, e-ISSN 1857-7415, p-ISSN 1409-7621, DOI: 10.2478/macvetrev-2022-0018, 2022