136 Influence of sex-sorted semen on developmental competency of cattle oocytes
M. D. Sebopela A B , M. L. Mphaphathi A , S. M. Sithole A B and T. L. Nedambale A BA Agricultural Research Council, Animal Production, Germplasm, Conservation, Reproductive and Biotechnologies, Irene, RSA
B Tshwane University of Technology, Department of Animal Science, Private Bag X680, Pretoria, RSA
Reproduction, Fertility and Development 35(2) 196-196 https://doi.org/10.1071/RDv35n2Ab136
Published: 5 December 2022
© 2023 The Author(s) (or their employer(s)). Published by CSIRO Publishing on behalf of the IETS
The present study aimed to investigate the fertilisation rate competency of cattle oocytes fertilised with sex-sorted or unsorted frozen-thawed semen. Heterogeneous cattle ovaries of unknown reproductive status were collected at the local abattoir. A total of 200 oocytes were recovered from ovaries using the aspiration method. Collected oocytes were matured in 500 µL of TCM 199 medium supplemented with 10% fetal bovine serum, follicular stimulating hormone, luteinising hormone, and oestradiol hormone, then covered with 250 µL of mineral oil. A total of 75 oocytes were in vitro fertilised per treatment with sex-sorted and unsorted frozen-thawed semen of proven fertility collected from the same bull purchased from American Breeders Service Global Inc. Co. The data were analysed as a complete randomised design with the experiment replicated five times. An analysis of variance (ANOVA) was performed. Comparisons were considered significantly different with P < 0.05 using Fisher’s protected least significant difference test. All the aforementioned analyses were performed using SAS 9.2 statistical software for continuous variables, means, and standard errors (SAS, 1999). There was a significant difference in the percentages of the unfertilised oocytes (without pronucleus) of sex-sorted (77.0 ± 2.6) and unsorted (64.6 ± 8.5) semen. The fertilisation rate (with two pronuclei) of sex-sorted semen (23.0 ± 2.6) was lower compared to unsorted semen (35.3 ± 8.5) (P < 0.05). The cleavage rate percentage observed in presumptive zygotes fertilised with sex-sorted semen (26.00 ± 5.2) was found to be low compared to the unsorted semen (42.67 ± 1.15) (P < 0.05). In conclusion, oocytes fertilised with unsorted semen had a higher fertilisation and cleavage rate percentage; however, there was a higher percentage of unfertilised oocytes with sex-sorted semen, resulting in low oocyte developmental competency.
The authors acknowledge the Agricultural Research Council, the Department of Agriculture, Land Reform and Rural Development, and National Research Foundation.
