Reproduction, Fertility and Development Reproduction, Fertility and Development Society
Vertebrate reproductive science and technology
RESEARCH ARTICLE

In vitro characterisation of fresh and frozen sex-sorted bull spermatozoa

Shauna A. Holden A , Craig Murphy A , Juan F. Moreno B , Stephen T. Butler C , Andrew R. Cromie D , Patrick Lonergan E and Sean Fair A F
+ Author Affiliations
- Author Affiliations

A Laboratory of Animal Reproduction, Department of Life Sciences, Faculty of Science and Engineering, University of Limerick, Castletroy, Limerick, Ireland.

B Sexing Technologies, Navasota, 22575 Highway 6 South, TX 77868, USA.

C Teagasc Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland.

D Irish Cattle Breeding Federation, Highfield House, Shinagh, Bandon, Co. Cork, Ireland.

E School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Dublin, Ireland.

F Corresponding author. Email: sean.fair@ul.ie

Reproduction, Fertility and Development 29(7) 1415-1425 https://doi.org/10.1071/RD16086
Submitted: 4 November 2015  Accepted: 17 May 2016   Published: 4 July 2016

Abstract

This study sought to compare the in vitro characteristics of fresh and frozen non-sorted (NS) and sex-sorted (SS) bull spermatozoa. Experiment 1: Holstein–Friesian ejaculates (n = 10 bulls) were split across four treatments and processed: (1) NS fresh at 3 × 106 spermatozoa, (2) X-SS frozen at 2 × 106 spermatozoa, (3) X-SS fresh at 2 × 106 spermatozoa and (4) X-SS fresh at 1 × 106 spermatozoa. NS frozen controls of 20 × 106 spermatozoa per straw were sourced from previously frozen ejaculates (n = 3 bulls). Experiment 2: Aberdeen Angus ejaculates (n = 4 bulls) were split across four treatments and processed as: (1) NS fresh 3 × 106 spermatozoa, (2) Y-SS fresh at 1 × 106 spermatozoa, (3) Y-SS fresh at 2 × 106 spermatozoa and (4) X-SS fresh at 2 × 106 spermatozoa. Controls were sourced as per Experiment 1. In vitro assessments for progressive linear motility, acrosomal status and oxidative stress were carried out on Days 1, 2 and 3 after sorting (Day 0 = day of sorting. In both experiments SS fresh treatments had higher levels of agglutination in comparison to the NS fresh (P < 0.001), NS frozen treatments had the greatest PLM (P < 0.05) and NS spermatozoa exhibited higher levels of superoxide anion production compared with SS spermatozoa (P < 0.05). Experiment 1 found both fresh and frozen SS treatments had higher levels of viable acrosome-intact spermatozoa compared with the NS frozen treatments (P < 0.01).

Additional keywords: agglutination, bovine, gender bias, oxidative stress, sexed semen.


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