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Mouse Oocyte Microinjection, Maturation and Ploidy Assessment
Published on: July 23, 2011
Pronuclear formation of freeze-dried canine spermatozoa microinjected into mouse oocytes
Hiroyuki Watanabe1, Tomoyoshi Asano, Yasuyuki Abe
1Department of Food Production Science, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Japan.
Purpose:
The aim of the present study was to investigate the fertilizing capacity of fresh, frozen-thawed and freeze-dried canine spermatozoa.
Methods:
After canine spermatozoa were injected into mouse oocytes, the rates of oocyte activation, male pronuclear formation and chromosomal aberrations were investigated.
Results:
The rates of oocyte activation were comparable (90.6-100%), no matter the sperm type injected. The percentage of male pronuclear formation was higher (P < 0.001) in the freeze-dried spermatozoa (92.3%) than the fresh (61.5%) and frozen-thawed (69.2%) spermatozoa. However, the chromosomal damage in the oocytes injected with freeze-dried spermatozoa was higher (72.9%: P < 0.001) than with fresh (26.9%) and frozen-thawed (21.4%) spermatozoa.
Conclusions:
These data indicate using mouse oocytes that freeze-dried canine spermatozoa may potentially fertilize canine oocytes although chromosomal damage is frequently generated.
Insights
Freeze-dried canine spermatozoa show potential for fertilization, but may cause chromosomal damage in oocytes. Further research is needed to assess the safety and efficacy of this sperm preservation method.
Area of Science:
- Reproductive Biology
- Animal Science
- Sperm Cryopreservation
Background:
- Sperm preservation techniques are crucial for canine reproduction.
- Evaluating the fertilizing capacity of different sperm preservation methods is essential.
Purpose of the Study:
- To investigate the fertilizing capacity of fresh, frozen-thawed, and freeze-dried canine spermatozoa.
- To assess the impact of different sperm preservation methods on canine oocyte activation, male pronuclear formation, and chromosomal aberrations.
Main Methods:
- Canine spermatozoa (fresh, frozen-thawed, freeze-dried) were injected into mouse oocytes.
- Oocyte activation rates were measured.
- Male pronuclear formation and chromosomal aberrations were analyzed.
Main Results:
- Oocyte activation rates were high and comparable across all sperm types (90.6-100%).
- Freeze-dried canine spermatozoa resulted in a significantly higher rate of male pronuclear formation (92.3%) compared to fresh (61.5%) and frozen-thawed (69.2%) spermatozoa.
- A significantly higher incidence of chromosomal damage was observed in oocytes injected with freeze-dried spermatozoa (72.9%) compared to fresh (26.9%) and frozen-thawed (21.4%) spermatozoa.
Conclusions:
- Freeze-dried canine spermatozoa demonstrate fertilizing potential when assessed in mouse oocytes.
- The use of freeze-dried canine spermatozoa is associated with a high frequency of chromosomal damage.
- Further investigation is warranted to determine the viability and safety of freeze-dried canine spermatozoa for assisted reproductive technologies.
