Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Jan;24(1):e10.
doi: 10.4142/jvs.22168. Epub 2022 Oct 14.

In vitro embryo production from ewes at different physiological stages

Alfredo Lorenzo-Torres  1 , Raymundo Rangel-Santos  2 , Agustín Ruíz-Flores  1 , Demetrio Alonso Ambríz-García  3
Affiliations

In vitro embryo production from ewes at different physiological stages

Alfredo Lorenzo-Torres et al. J Vet Sci. 2023 Jan.

Abstract

Background: The collection of ovaries from slaughterhouses is an important source of oocytes for in vitro embryo production. On the other hand, the physiological stage of slaughtered females varies and influences embryo production.

Objectives: The study examined the in vitro efficiency of embryos and demi-embryos from young, non-pregnant adult, and pregnant adult ewes from a local slaughterhouse.

Methods: One thousand three hundred ovaries were collected from August to October 2020. The recovered oocytes were matured, fertilized, and cultured at 5% CO2, 38.5°C, and 100% humidity. Embryo bisection was performed in 96 blastocysts (n = 32 per treatment). The demi-embryo pairs were incubated for their reconstitution for 12 h. SAS was used for data analysis.

Results: The number of oocytes collected from the experimental group of non-pregnant adult ewes was higher (p ≤ 0.007) than those collected from the group of pregnant adult ewes (2.67 ± 0.19 vs. 2.18 ± 0.15 oocytes/group, respectively). The blastocyst rate was higher (p ≤ 0.0001) in the non-pregnant adult group (36.39%) than in the young (17.96%). The ratio of demi-embryos that recovered the blastocoelic cavity was higher (p < 0.05) in the young group (81.25%) than in the pregnant adult group (59.38%). The diameter of the demi-embryos was higher (p < 0.05) in the non-pregnant adult group (186.54 ± 8.70 μm) than those in the young and pregnant adult groups.

Conclusions: In conclusion, the in vitro embryo production efficiency was highest when using oocytes from non-pregnant adult ewes under the conditions of this study.

Keywords: Sheep; embryonic development; in vitro fertilization.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Fig. 1
Fig. 1. Embryo bisection process and demi-embryo survival after 12 h of in vitro culture. (A) Expanded blastocyst, (B) pair of demi-embryos, and (C) reconstituted demi-embryos (×200).
Fig. 2
Fig. 2. Mean diameter of demi-embryos (after 12 h of culture) produced from slaughtered ewes at different physiological stages. Each bar represents the least-squares mean ± standard error. Different superscript letters (a and b) between columns represent the significant differences (p < 0.05).
See this image and copyright information in PMC

References

    1. Godke RA, Sansinena M, Youngs CR. In: Transgenic Animal Technology: A Laboratory Handbook. 3rd ed. Pinkert CA, editor. Amsterdam: Elsevier; 2014. Assisted reproductive technologies and embryo culture methods for farm animals; pp. 581–638.
    1. Hashiyada Y. The contribution of efficient production of monozygotic twins to beef cattle breeding. J Reprod Dev. 2017;63(6):527–538. - PMC - PubMed
    1. Dadashpour Davachi N, Zare Shahneh A, Kohram H, Zhandi M, Dashti S, Shamsi H, et al. In vitro ovine embryo production: the study of seasonal and oocyte recovery method effects. Iran Red Crescent Med J. 2014;16(9):e20749. - PMC - PubMed
    1. Wani NA, Wani GM, Khan MZ, Salahudin S. Effect of oocyte harvesting techniques on in vitro maturation and in vitro fertilization in sheep. Small Rumin Res. 2000;36(1):63–67.
    1. Leoni GG, Palmerini MG, Satta V, Succu S, Pasciu V, Zinellu A, et al. Differences in the kinetic of the first meiotic division and in active mitochondrial distribution between prepubertal and adult oocytes mirror differences in their developmental competence in a sheep model. PLoS One. 2015;10(4):e0124911. - PMC - PubMed