Morphology, developmental stages and quality parameters of in vitro-produced equine embryos
Elaine M. Carnevale A C and Elizabeth S. Metcalf BA Department of Biomedical Sciences, Colorado State University, 1693 Campus Delivery, Fort Collins, CO 80523, USA.
B Departments of Obstetrics and Gynecology, and Andrology, Oregon Health Science and University, 3181 SW Sam Jackson Park Road, Portland, OR 97239-3098, USA.
C Corresponding author. Email: elaine.carnevale@colostate.edu
Reproduction, Fertility and Development 31(12) 1758-1770 https://doi.org/10.1071/RD19257
Submitted: 2 July 2019 Accepted: 18 October 2019 Published: 13 November 2019
Abstract
Intracytoplasmic sperm injection (ICSI) is used to produce equine embryos in vitro. The speed of embryo development in vitro is roughly equivalent to what has been described for embryos produced in vivo. Morphological evaluations of ICSI-produced embryos are complicated by the presence of debris and the dark nature of equine embryo cytoplasm. Morulas and early blastocysts produced in vitro appear similar to those produced in vivo. However, with expansion of the blastocyst, distinct differences are observed compared with uterine embryos. In culture, embryos do not undergo full expansion and thinning of the zona pellucida (ZP) or capsule formation. Cells of the inner cell mass (ICM) are dispersed, in contrast with the differentiated trophoblast and ICM observed in embryos collected from uteri. As blastocysts expand in vitro, embryo cells often escape the ZP as organised or disorganised extrusions of cells, probably through the hole incurred during ICSI. Quality assessment of in vitro-produced early stage equine embryos is in its infancy, because limited information is available regarding the relationship between morphology and developmental competence. Early embryo development in vivo is reviewed in this paper, with comparisons made to embryo development in vitro and clinical assessments from a laboratory performing commercial ICSI for >15 years.
Additional keywords: intracytoplasmic sperm injection (ICSI), oocyte, zygote.
References
Altermatt, J. L., Suh, T. K., Stokes, J. E., and Carnevale, E. M. (2009). Effects of age and equine follicle-stimulating hormone (eFSH) on collection and viability of equine oocytes assessed by morphology and developmental competency after intracytoplasmic sperm injection (ICSI). Reprod. Fertil. Dev. 21, 615–623.| Effects of age and equine follicle-stimulating hormone (eFSH) on collection and viability of equine oocytes assessed by morphology and developmental competency after intracytoplasmic sperm injection (ICSI).Crossref | GoogleScholarGoogle Scholar | 19383268PubMed |
Ambruosi, B., Lacalandra, G. M., Iorga, A. I., De Santis, T., Mugnier, S., Matarrese, R., Goudet, G., and Dell’Aquila, M. E. (2009). Cytoplasmic lipid droplets and mitochondrial distribution in equine oocytes: implications on oocyte maturation, fertilization and developmental competence after ICSI. Theriogenology 71, 1093–1104.
| Cytoplasmic lipid droplets and mitochondrial distribution in equine oocytes: implications on oocyte maturation, fertilization and developmental competence after ICSI.Crossref | GoogleScholarGoogle Scholar | 19167745PubMed |
Betteridge, K. J. (1989). The structure and function of the equine capsule in relation to embryo manipulation and transfer. Equine Vet. J. 21, 92–100.
| The structure and function of the equine capsule in relation to embryo manipulation and transfer.Crossref | GoogleScholarGoogle Scholar |
Betteridge, K. J., Eaglesome, M. D., Mitchell, D., Flood, P. F., and Beriault, R. (1982). Development of horse embryos up to twenty two days after ovulation: observations on fresh specimens. J. Anat. 135, 191–209.
| 7130052PubMed |
Bezard, J., Magistrini, M., Duchamp, G., and Palmer, E. (1989). Chronology of equine fertilization and embryonic development in vivo and in vitro. Equine Vet. J. 21, 105–110.
| Chronology of equine fertilization and embryonic development in vivo and in vitro.Crossref | GoogleScholarGoogle Scholar |
Brinsko, S. P., Ball, B. A., Ignotz, G. G., Thomas, P. G. A., Currie, W. B., and Ellington, J. E. (1995). Initiation of transcription and nucleologenesis in equine embryos. Mol. Reprod. Dev. 42, 298–302.
| Initiation of transcription and nucleologenesis in equine embryos.Crossref | GoogleScholarGoogle Scholar | 8579843PubMed |
Burruel, V., Klooster, K., Barker, C. M., Riejo Pera, R., and Meyers, S. (2014). Abnormal early cleavage events predict early embryo demise: sperm oxidative stress and early abnormal cleavage. Sci. Rep. 4, 6598.
| Abnormal early cleavage events predict early embryo demise: sperm oxidative stress and early abnormal cleavage.Crossref | GoogleScholarGoogle Scholar | 25307782PubMed |
Carnevale, E. M., Griffin, P. G., and Ginther, O. J. (1993). Age-associated subfertility before entry of embryos into the uterus in mares. Equine Vet. J. Suppl. 15, 31–35.
| Age-associated subfertility before entry of embryos into the uterus in mares.Crossref | GoogleScholarGoogle Scholar |
Carnevale, E. M., Uson, M., Bozzola, J. J., King, S. S., Schmitt, S. J., and Gates, H. D. (1999). Comparison of oocytes from young and old mares with light and electron microscopy. Theriogenology 51, 299.
| Comparison of oocytes from young and old mares with light and electron microscopy.Crossref | GoogleScholarGoogle Scholar |
Carnevale, E. M., Ramirez, R. J., Squires, E. L., Alvarenga, M. A., Vanderwall, D. K., and McCue, P. M. (2000). Factors affecting pregnancy rates and early embryonic death after equine embryo transfer. Theriogenology 54, 965–979.
| Factors affecting pregnancy rates and early embryonic death after equine embryo transfer.Crossref | GoogleScholarGoogle Scholar | 11097048PubMed |
Choi, Y. H., Love, C. C., Love, L. B., Varner, D. D., Brinsko, S., and Hinrichs, K. (2002). Developmental competence in vivo and in vitro of in vitro-matured equine oocytes fertilized by intracytoplasmic sperm injection with fresh or frozen–thawed spermatozoa. Reproduction 123, 455–465.
| Developmental competence in vivo and in vitro of in vitro-matured equine oocytes fertilized by intracytoplasmic sperm injection with fresh or frozen–thawed spermatozoa.Crossref | GoogleScholarGoogle Scholar | 11882023PubMed |
Choi, Y. H., Love, L. B., Varner, D. D., and Hinrichs, K. (2004). Factors affecting developmental competence of equine oocytes after intracytoplasmic sperm injection. Reproduction 127, 187–194.
| Factors affecting developmental competence of equine oocytes after intracytoplasmic sperm injection.Crossref | GoogleScholarGoogle Scholar | 15056784PubMed |
Choi, Y. H., Harding, H. D., Hartman, D. L., Obermiller, A. D., Kurosaka, S., McLaughlin, K. J., and Hinrichs, K. (2009). The uterine environment modulates trophectodermal POU5F1 levels in equine blastocysts. Reproduction 138, 589–599.
| The uterine environment modulates trophectodermal POU5F1 levels in equine blastocysts.Crossref | GoogleScholarGoogle Scholar | 19525365PubMed |
Choi, Y. H., Ross, P., Velez, I. C., Macias-Garcia, B., Riera, F. L., and Hinrichs, K. (2015). Cell lineage allocation in equine blastocysts produced in vitro under varying glucose concentrations. Reproduction 150, 31–41.
| Cell lineage allocation in equine blastocysts produced in vitro under varying glucose concentrations.Crossref | GoogleScholarGoogle Scholar | 25852156PubMed |
Daughtry B. L.Chavez S. L. (2018 ).
Daughtry, B. L., Masterson, K. R., Metcalf, E. S., Battaglia, D., Fei, S. S., Carbone, L., Beck, R., Cook, N., and Chavez, S. L. (2016). Combining time-lapse imaging and next generation RNA-sequencing to assess equine embryo developmental potential. J. Equine Vet. Sci. 41, 80–81.
| Combining time-lapse imaging and next generation RNA-sequencing to assess equine embryo developmental potential.Crossref | GoogleScholarGoogle Scholar |
in press
Dijkstra, A., Cuervo-Arango, J., Stout, T. A. E., and Claes, A. (2019). Monozygotic multiple pregnancies after transfer of single in vitro produced equine embryos. Equine Vet. J. , .
| Monozygotic multiple pregnancies after transfer of single in vitro produced equine embryos.Crossref | GoogleScholarGoogle Scholar |
in press
Frank, B. L., Doddman, C. D., Stokes, J. E., and Carnevale, E. M. (2019). Association of equine oocyte and cleavage-stage embryo morphology with maternal age and pregnancy after intracytoplasmic sperm injection. Reprod. Fertil. Dev. , .
| Association of equine oocyte and cleavage-stage embryo morphology with maternal age and pregnancy after intracytoplasmic sperm injection.Crossref | GoogleScholarGoogle Scholar |
Freeman, D. A., Weber, J. A., Geary, R. T., and Woods, G. L. (1991). Time of embryo transport through the mare oviduct. Theriogenology 36, 823–830.
| Time of embryo transport through the mare oviduct.Crossref | GoogleScholarGoogle Scholar | 16727051PubMed |
Gardner, D. K., and Balaban, B. (2016). Assessment of human embryo development using morphological criteria in an era of time-lapse, alogorithms and ‘OMICS’: is looking good still important? Mol. Hum. Reprod. 22, 704–718.
| Assessment of human embryo development using morphological criteria in an era of time-lapse, alogorithms and ‘OMICS’: is looking good still important?Crossref | GoogleScholarGoogle Scholar | 27578774PubMed |
Grøndahl, C., Hyttel, P., Grøndahl, M. L., Eriksen, T., Gotfredsen, P., and Greve, T. (1995). Structural and endocrine aspects of equine oocyte maturation in vivo. Mol. Reprod. Dev. 42, 94–105.
| Structural and endocrine aspects of equine oocyte maturation in vivo.Crossref | GoogleScholarGoogle Scholar | 8562057PubMed |
Hamilton, W. J., and Day, F. T. (1945). Cleavage stages of the ova of the horse, with notes on ovulation. J Anat. 79, 127–130.3.
| Cleavage stages of the ova of the horse, with notes on ovulation.Crossref | GoogleScholarGoogle Scholar | 17104976PubMed |
Hardarson, T., Hanson, C., Sjögren, A., and Lundin, K. (2001). Human embryos with unevenly sized blastomeres have lower pregnancy and implantation rates: indications for aneuploidy and multinucleation. Hum. Reprod. 16, 313–318.
| Human embryos with unevenly sized blastomeres have lower pregnancy and implantation rates: indications for aneuploidy and multinucleation.Crossref | GoogleScholarGoogle Scholar | 11157826PubMed |
Hendriks, W. K., Colleoni, S., Galli, G., Paris, D. B. B. P., Colenbrander, B., and Stout, T. A. E. (2019). Mitochondrial DNA replication is initiated at blastocyst formation in equine embryos. Reprod. Fertil. Dev. 31, 570–578.
| Mitochondrial DNA replication is initiated at blastocyst formation in equine embryos.Crossref | GoogleScholarGoogle Scholar | 30423285PubMed |
Lewis, N., Hinrichs, K., Schnauffer, K., Morganti, M., and Argo, C. McG. (2016). Effect of oocyte source and transport time on rates of equine oocyte maturation and cleavage after fertilization by ICSI, with a note on the validation of equine embryo morphological classification. Clin. Theriogenol. 8, 25–39.
Magli, M. C., Gianaroli, L., Ferraretti, A. P., Lappi, M., Ruberti, A., and Farfalli, V. (2007). Embryo morphology and development are dependent on the chromosomal complement. Fertil. Steril. 87, 534–541.
| Embryo morphology and development are dependent on the chromosomal complement.Crossref | GoogleScholarGoogle Scholar | 17123520PubMed |
McCue, P. M., DeLuca, C. A., Ferris, R. A., and Wall, J. J. (2009). How to evaluate equine embryos. AAEP Proc. 55, 252–256.
Oriol, J. G., Betteridge, K. J., Clarke, A. J., and Sharom, F. J. (1993). Mucin-like glycoproteins in the equine embryonic capsule. Mol. Reprod. Dev. 34, 255–265.
| Mucin-like glycoproteins in the equine embryonic capsule.Crossref | GoogleScholarGoogle Scholar | 8471247PubMed |
Prados, F. J., Debrock, S., Lemmen, J. G., and Agerholm, I. (2012). The cleavage stage embryo. Hum. Reprod. 27, i50–i71.
| The cleavage stage embryo.Crossref | GoogleScholarGoogle Scholar | 22752610PubMed |
Racowsky, C., Combelles, C. M. H., Nureddin, A., Pan, Y., Finn, A., Miles, L., Gale, S., O’Leary, T., and Jackson, K. V. (2003). Day 3 and Day 5 morphology predictors of embryo viability. Reprod. Biomed. Online 6, 323–331.
| Day 3 and Day 5 morphology predictors of embryo viability.Crossref | GoogleScholarGoogle Scholar | 12735868PubMed |
Rienzi, L., Ubaldi, F., Iacobelli, M., Romano, S., Giulia Minasi, M., Ferrero, S., Sapienza, F., Baroni, E., and Greco, E. (2005). Significance of morphological attributes of the early embryo. Reprod. Biomed. Online 10, 669–681.
| Significance of morphological attributes of the early embryo.Crossref | GoogleScholarGoogle Scholar | 15949228PubMed |
Roberts, M. A., London, K., Campos-Chillon, L. F., and Altermatt, J. L. (2015). Presumed monozygotic twins develop following transfer of an in vitro-produced equine embryo. J. Equine Sci. 26, 89–94.
| Presumed monozygotic twins develop following transfer of an in vitro-produced equine embryo.Crossref | GoogleScholarGoogle Scholar | 26435682PubMed |
Ruggeri, E., DeLuca, K. F., Galli, C., Lazzari, G., DeLuca, J. G., Stokes, J. E., and Carnevale, E. M. (2017). Use of confocal microscopy to evaluate equine zygote development after sperm injection of oocytes matured in vivo or in vitro. Microsc Microanal. 23, 1197–1206.
| Use of confocal microscopy to evaluate equine zygote development after sperm injection of oocytes matured in vivo or in vitro.Crossref | GoogleScholarGoogle Scholar | 29208065PubMed |
Salgado, R. M., Brom-de-Luna, J. G., Resende, H. L., Canesin, H. S., and Hinrichs, K. (2018). Lower blastocyst quality after conventional vs. Piezo ICSI in the horse reflects delayed sperm component remodeling and oocyte activation. J. Assist. Reprod. Genet. 35, 825–840.
| Lower blastocyst quality after conventional vs. Piezo ICSI in the horse reflects delayed sperm component remodeling and oocyte activation.Crossref | GoogleScholarGoogle Scholar | 29637506PubMed |
Stensen, M. H., Tanbo, T. G., Storeng, R., Abyholm, T., and Fedorcsak, P. (2015). Fragmentation of human cleavage-stage embryos is related to the progression through meiotic and mitotic cell cycles. Fertil. Steril. 103, 374–381.e4.
| Fragmentation of human cleavage-stage embryos is related to the progression through meiotic and mitotic cell cycles.Crossref | GoogleScholarGoogle Scholar | 25467039PubMed |
Stout, T. A. E., Meadows, S., and Allen, W. R. (2005). Stage-specific formation of the equine blastocyst capsule is instrumental to hatching and to embryonic survival in vivo. Anim. Reprod. Sci. 87, 269–281.
| Stage-specific formation of the equine blastocyst capsule is instrumental to hatching and to embryonic survival in vivo.Crossref | GoogleScholarGoogle Scholar |
Sugimura, S., Akai, T., and Imai, K. (2017). Selection of viable in vitro-fertilized bovine embryos using time-lapse monitoring in microwell culture dishes. J. Reprod. Dev. 63, 353–357.
| Selection of viable in vitro-fertilized bovine embryos using time-lapse monitoring in microwell culture dishes.Crossref | GoogleScholarGoogle Scholar | 28552887PubMed |
Tremoleda, J. L., Stout, T. A. E., Lagutina, I., Lazzari, G., Bevers, M. M., Colebrander, B., and Galli, C. (2003). Effects of in vitro production on horse embryo morphology, cytoskeletal characteristics, and blastocyst capsule formation. Biol. Reprod. 69, 1895–1906.
| Effects of in vitro production on horse embryo morphology, cytoskeletal characteristics, and blastocyst capsule formation.Crossref | GoogleScholarGoogle Scholar | 12904313PubMed |
Van Royen, E., Mangelschots, K., De Neubourg, D., Valkenburg, M., Van de Meerssche, M., Rychaert, G., Eestermans, W., and Gerris, J. (1999). Characterization of a top quality embryo, as step towards single-embryo transfer. Hum. Reprod. 14, 2345–2349.
| Characterization of a top quality embryo, as step towards single-embryo transfer.Crossref | GoogleScholarGoogle Scholar | 10469708PubMed |
Vanderwall, D. K. (1996). Early embryonic development and evaluation of equine embryo viability. Vet. Clin. North Am. Equine Pract. 12, 61–83.
| 8726450PubMed |
Webel, S. K., Franklin, V., Hardland, B., and Dziuk, P. J. (1977). Fertility, ovulation and maturation of eggs in mares injected with HCG. J. Reprod. Fertil. 51, 337–341.
| Fertility, ovulation and maturation of eggs in mares injected with HCG.Crossref | GoogleScholarGoogle Scholar | 563450PubMed |
Weinerman, R., Feng, R., Ord, T. S., Schultz, R. M., Bartolomei, M. S., Coutifaris, C., and Mainigi, M. (2016). Morphokinetic evaluation of embryo development in a mouse model: functional and molecular correlates. Biol. Reprod. 94, 84.
| Morphokinetic evaluation of embryo development in a mouse model: functional and molecular correlates.Crossref | GoogleScholarGoogle Scholar | 26911427PubMed |