<abstract xmlns="http://www.w3.org/1999/xhtml"><p> Science has been searching for a long time for a reliable method for controlling the sex of mammalian offspring. Recently, the application of specific modern cellular methodologies has led to the development of a flow cytometric system capable of differentiating and separating living X- and Y-chromosome-bearing sperm cells in amounts suitable for AI and therefore, commercialization of this sexing technology. The aim of this work was to present the first results of heifers that introduce bovine AI with sex sorted semen, for the first time in Macedonia. Insemination with sex sorted cryopreserved semen (2×10<sup>6</sup> spermatozoa per dose) imported from the USA was done at two dairy farms in ZK Pelagonija. In total, 74 heifers (Holstein Friesian) were inseminated. Inseminations were carried out in a timely manner following a modified OvSynch protocol. During the insemination, the sperm was deposited into the uterine horn ipsi lateral to the ovary where a follicle larger than 1.6 cm was detected by means of transrectal ultrasound examination. Pregnancy was checked by ultrasound on day 30 after the insemination. Overall, the average pregnancy rate in both farms was 43,24% (40,54% and 45,95%, for farm 1 and farm 2, respectively). All pregnant heifers delivered their calves following a normal gestation length (274,3 days in average) and of the 32 born calves, 30 (93,75%) were female. In conclusion, since the first results from inseminations with sex-sorted semen in dairy heifers in Macedonia are very promising, the introduction of this technique may bring much benefit to the local dairy sector. Average pregnancy rate seems similar with results obtained following ‘regular’ inseminations, notwithstanding the relatively low number of spermatozoa per insemination dose. Due to the latter, we however recommend inseminations only to be carried out by experienced technicians followinga TAI protocol and ultrasound examinations of the ovaries prior to insemination.</p></abstract>

Science has been searching for a long time for a reliable method for controlling the sex of mammalian offspring. Recently, the application of specific modern cellular methodologies has led to the development of a flow cytometric system capable of differentiating and separating living X- and Y-chromosome-bearing sperm cells in amounts suitable for AI and therefore, commercialization of this sexing technology. The aim of this work was to present the first results of heifers that introduce bovine AI with sex sorted semen, for the first time in Macedonia. Insemination with sex sorted cryopreserved semen (2×106 spermatozoa per dose) imported from the USA was done at two dairy farms in ZK Pelagonija. In total, 74 heifers (Holstein Friesian) were inseminated. Inseminations were carried out in a timely manner following a modified OvSynch protocol. During the insemination, the sperm was deposited into the uterine horn ipsi lateral to the ovary where a follicle larger than 1.6 cm was detected by means of transrectal ultrasound examination. Pregnancy was checked by ultrasound on day 30 after the insemination. Overall, the average pregnancy rate in both farms was 43,24% (40,54% and 45,95%, for farm 1 and farm 2, respectively). All pregnant heifers delivered their calves following a normal gestation length (274,3 days in average) and of the 32 born calves, 30 (93,75%) were female. In conclusion, since the first results from inseminations with sex-sorted semen in dairy heifers in Macedonia are very promising, the introduction of this technique may bring much benefit to the local dairy sector. Average pregnancy rate seems similar with results obtained following ‘regular’ inseminations, notwithstanding the relatively low number of spermatozoa per insemination dose. Due to the latter, we however recommend inseminations only to be carried out by experienced technicians followinga TAI protocol and ultrasound examinations of the ovaries prior to insemination.

First Results from Insemination With Sex-Sorted Semen in Dairy Heifers in Macedonia

Faculty of Biotechnical Sciences Bitola, University “St. Kliment Ohridski” – Bitola, Partizanska bb, 7000 Bitola, Macedonia

Faculty of Biotechnical Sciences, Bitola University “St. Kliment Ohridski” – Bitola Partizanska bb, 7000 Bitola Macedonia

ZK Pelagonija Bitola, Boris Kidrik 3, 7000 Bitola, Macedonia

Macedonian Veterinary Review

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Science has been searching for a long time for a reliable method for controlling the sex of mammalian offspring. Recently, the application of specific modern...

First Results from Insemination With Sex-Sorted Semen in Dairy Heifers in Macedonia

Published Online: Nov 18, 2015

Page range: 107 - 111

Received: Jun 03, 2014

Accepted: Oct 15, 2014

DOI: https://doi.org/10.14432/j.macvetrev.2014.10.025

Keywords
sperm sexing, heifer, ultrasound, artificial insemination

© 2015

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

First Results from Insemination With Sex-Sorted Semen in Dairy Heifers in Macedonia

Published Online: Nov 18, 2015

Page range: 107 - 111

Received: Jun 03, 2014

Accepted: Oct 15, 2014

DOI: https://doi.org/10.14432/j.macvetrev.2014.10.025

Keywordssperm sexing, heifer, ultrasound, artificial insemination

© 2015

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Keywords
sperm sexing, heifer, ultrasound, artificial insemination