Bovine Sperm Sexing Alters Sperm Morphokinetics and Subsequent Early Embryonic Development.
Animals
Cattle
Cell Separation
/ methods
Cryopreservation
Embryo, Mammalian
/ diagnostic imaging
Embryonic Development
/ physiology
Female
Fertilization in Vitro
/ methods
Flow Cytometry
/ methods
In Vitro Oocyte Maturation Techniques
/ methods
Male
Microscopy, Video
Oocytes
/ growth & development
Pregnancy
Semen Analysis
Spermatozoa
/ growth & development
Time-Lapse Imaging
Journal
Scientific reports
ISSN: 2045-2322
Titre abrégé: Sci Rep
Pays: England
ID NLM: 101563288
Informations de publication
Date de publication:
10 04 2020
10 04 2020
Historique:
received:
27
10
2019
accepted:
20
03
2020
entrez:
12
4
2020
pubmed:
12
4
2020
medline:
15
12
2020
Statut:
epublish
Résumé
In artificial insemination the use of sex-sorted bovine sperm results in reduced conception, the causes of which are only partly understood. Therefore, we set out to investigate the effects of sexing on bovine sperm function and early embryonic development. Computer-assisted semen analysis (CASA) of sperm of the same bulls (n = 5), before and after sexing, demonstrated significantly reduced fast (A) and slow (B) progressively motile sperm (p < 0.05) after sexing. Sexed-sperm also revealed significantly less hyperactivated sperm (p < 0.05). As shown by time-lapse videomicroscopy of in vitro produced embryos (n = 360), embryos derived from sexed-sperm displayed significantly increased incidences of arrest at the 4-cell stage (p < 0.05). The relative risk for shrinkage/fusion of blastomeres with subsequent lysis was 1.71 times higher in the embryos derived from sexed-sperm as compared to conventional embryos (p < 0.05) resulting in significantly reduced blastocyst rates (p < 0.001). The relative risk for cleavage was 2.36 times lower in the embryos derived from sex-sorted sperm (p < 0.001). Additionally, sexed-sperm-derived embryos showed reduced survival times (hazard ratio HR = 1.54, p < 0.001) which were bull dependent (p < 0.001). However, the percentage of apoptotic cells was similar to conventional embryos. Furthermore, embryos derived from sexed-sperm were found to reach developmental stages at similar timings as conventional embryos. Our results suggest that reduced conception rates after sexing are due to altered sperm morphokinetics, decreasing the chance of sperm to reach and fertilise the oocyte, and aberrant early embryonic development.
Identifiants
pubmed: 32277124
doi: 10.1038/s41598-020-63077-6
pii: 10.1038/s41598-020-63077-6
pmc: PMC7148378
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
6255Références
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