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Souza-Fabjan JMG, Leal GR, Monteiro CAS, Batista RITP, Barbosa NO, Freitas VJF. In vitro embryo production in small ruminants: what is still missing? Anim Reprod 2023; 20:e20230055. [PMID: 38025995 PMCID: PMC10681138 DOI: 10.1590/1984-3143-ar2023-0055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 07/18/2023] [Indexed: 12/01/2023] Open
Abstract
In vitro embryo production (IVEP) is an extremely important tool for genetic improvement in livestock and it is the biotechnology that has grown the most recently. However, multiple ovulation followed by embryo transfer is still considered the leading biotechnology for embryo production in small ruminants. This review aimed to identify what is still missing for more efficient diffusion of IVEP in small ruminants, going through the IVEP steps and highlighting the main factors affecting the outcomes. Oocyte quality is essential for the success of IVEP and an aspect to be considered in small ruminants is their reproductive seasonality and strategies to mitigate the effect of season. The logistics for oocyte collection from live females is more complex than in cattle, and tools to simplify this collection system and/or to promote an alternative way of recovering oocytes may be an important point in this scenario. The heterogeneity of oocytes collected from growing follicles in live females or from ovaries collected from abattoirs remains a challenge, and there is a demand to standardize/homogenize the hormonal stimulatory protocols and IVM protocols for each source of oocytes. The use of sexed semen is technically possible, however the low market demand associated with the high costs of the sexing process prevents the routine use of this technique, but its higher availability is an important aspect aiming for greater dissemination of IVEP. New noninvasive approaches for embryo selection are key factors since the selection for transfer or cryopreservation is another difficulty faced among laboratories. Embryo selection is based on morphological traits, although these are not necessarily reliable in predicting pregnancy. Several issues described in this review must be considered by researchers in other to promote the diffusion of IVEP in small ruminants.
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Affiliation(s)
| | - Gabriela Ramos Leal
- Faculdade de Veterinária, Universidade Federal Fluminense, Niterói, RJ, Brasil
| | | | | | | | - Vicente José Figueirêdo Freitas
- Laboratório de Fisiologia e Controle da Reprodução, Faculdade de Veterinária, Universidade Estadual do Ceará, Fortaleza, CE, Brasil
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Falchi L, Ledda S, Zedda MT. Embryo biotechnologies in sheep: Achievements and new improvements. Reprod Domest Anim 2022; 57 Suppl 5:22-33. [PMID: 35437835 PMCID: PMC9790389 DOI: 10.1111/rda.14127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/17/2022] [Indexed: 12/30/2022]
Abstract
To date, large-scale use of multiple ovulation and embryo transfer (MOET) programmes in ovine species is limited due to unpredictable results and high costs of hormonal stimulation and treatment. Therefore, even if considered reliable, they are not fully applicable in large-scale systems. More recently, the new prospects offered by in vitro embryo production (IVEP) through collection of oocytes post-mortem or by repeated ovum pick-up from live females suggested an alternative to MOET programmes and may be more extensively used, moving from the exclusive research in the laboratory to field application. The possibility to perform oocytes recovery from juvenile lambs to obtain embryos (JIVET) offers the great advantage to significantly reduce the generation interval, speeding the rate of genetic improvement. Although in the past decades several studies implemented novel protocols to enhance embryo production in sheep, the conditions of every single stage of IVEP can significantly affect embryo yield and successful transfer into the recipients. Moreover, the recent progresses on embryo production and freezing technologies might allow wider propagation of valuable genes in small ruminants populations and may be used for constitution of flocks without risks of disease. In addition, they can give a substantial contribution in preserving endangered breeds. The new era of gene editing might offer innovative perspectives in sheep breeding, but the application of such novel techniques implies involvement of specialized operators and is limited by relatively high costs for embryo manipulation and molecular biology analysis.
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Affiliation(s)
- Laura Falchi
- Sezione di Cl. Ostetrica e GinecologiaDipartimento di Medicina VeterinariaUniversità degli Studi di SassariSassariItaly
| | - Sergio Ledda
- Sezione di Cl. Ostetrica e GinecologiaDipartimento di Medicina VeterinariaUniversità degli Studi di SassariSassariItaly
| | - Maria T. Zedda
- Sezione di Cl. Ostetrica e GinecologiaDipartimento di Medicina VeterinariaUniversità degli Studi di SassariSassariItaly
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Novelties in Ovine Assisted Reproductive Technologies – A Review. MACEDONIAN VETERINARY REVIEW 2022. [DOI: 10.2478/macvetrev-2022-0018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Artificial insemination (AI) as a part of assisted reproductive technologies represents the oldest and most widespread method used to accelerate genetic progress in all domestic animals. After its first implementation in ovine reproduction and almost 80 years afterward, AI is continuously used for improving the genetic merit, utilizing either fresh or short-time chilled semen. Nevertheless, regardless of the semen used for insemination, the conception rate (CR) is still lower in comparison to natural service. At least two factors are commonly thought to limit the success of the AI and reduce the CR: (1) failure of placing the semen directly into the uterus due to the specific anatomic structure of the ewe’s cervix; (2) lower viability of ram spermatozoa during cryopreservation (<30% progressively motile spermatozoa after thawing). This review elaborates on recent studies that aimed to achieve acceptable CR through the implementation of cervical or intrauterine insemination: deep intracervical, intrauterine trans-cervical, and intracornual. Several hormonal treatments (oxytocin, estrogen, or prostaglandin) were evaluated on inducing cervical dilation that facilitates insemination. A comprehensive analysis was given to the effects of several antioxidants (GSSG, GSH, and cysteine) supplemented in ram semen-freezing media. Sex-sorted ram semen fertility rate results were presented from our studies.
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Souza-Fabjan JMG, Batista RITP, Correia LFL, Paramio MT, Fonseca JF, Freitas VJF, Mermillod P. In vitro production of small ruminant embryos: latest improvements and further research. Reprod Fertil Dev 2021; 33:31-54. [PMID: 38769678 DOI: 10.1071/rd20206] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024] Open
Abstract
This review presents the latest advances in and main obstacles to the application of invitro embryo production (IVEP) systems in small ruminants. This biotechnology is an extremely important tool for genetic improvement for livestock and is essential for the establishment of other biotechnologies, such as cloning and transgenesis. At present, the IVEP market is almost non-existent for small ruminants, in contrast with the trends observed in cattle. This is probably related to the lower added value of small ruminants, lower commercial demand and fewer qualified professionals interested in this area. Moreover, there are fewer research groups working on small ruminant IVEP than those working with cattle and pigs. The heterogeneity of oocytes collected from growing follicles in live females or from ovaries collected from abattoirs remains a challenge for IVEP dissemination in goats and sheep. Of note, although the logistics of oocyte collection from live small ruminant females are more complex than in the bovine, in general the IVEP outcomes, in terms of blastocyst production, are similar. We anticipate that after appropriate training and repeatable results, the commercial demand for small ruminant invitro -produced embryos may increase.
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Affiliation(s)
- Joanna M G Souza-Fabjan
- Faculdade de Veterinária, Universidade Federal Fluminense, Rua Vital Brazil Filho, 64, Niterói-RJ, CEP 24230-340, Brazil; and Corresponding author
| | - Ribrio I T P Batista
- Faculdade de Veterinária, Universidade Federal Fluminense, Rua Vital Brazil Filho, 64, Niterói-RJ, CEP 24230-340, Brazil
| | - Lucas F L Correia
- Faculdade de Veterinária, Universidade Federal Fluminense, Rua Vital Brazil Filho, 64, Niterói-RJ, CEP 24230-340, Brazil
| | - Maria Teresa Paramio
- Departament de Ciencia Animal i dels Aliments, Facultat de Veterinaria, Universitat Autonoma de Barcelona, 08193 Cerdanyola del Valles, Barcelona, Spain
| | - Jeferson F Fonseca
- Embrapa Caprinos e Ovinos, Rodovia MG 133, km 42, Campo Experimental Coronel Pacheco, Coronel Pacheco-MG, CEP 36155-000, Brazil
| | - Vicente J F Freitas
- Laboratório de Fisiologia e Controle da Reprodução, Universidade Estadual do Ceará, Fortaleza-CE, CEP 60714-903, Brazil
| | - Pascal Mermillod
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE), UMR7247, Physiologie de la Reproduction et des Comportements, Nouzilly, France
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Paramio MT, Izquierdo D. Current status of in vitro embryo production in sheep and goats. Reprod Domest Anim 2015; 49 Suppl 4:37-48. [PMID: 25277431 DOI: 10.1111/rda.12334] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 04/17/2014] [Indexed: 11/26/2022]
Abstract
Sheep and goat production is an important economic activity in Spain with an increasing interest in milk production. Multiovulation and Embryo Transfer (MOET) and In vitro Embryo Production (IVEP) are assisted reproductive technologies aimed at increasing the genetic diffusion of females. In vitro embryo production is a multi-step methodology comprising the following procedures: (i) In vitro Maturation (IVM) of oocytes recovered directly from the follicles, (ii) In vitro Fertilization (IVF) or co-incubation of capacitated spermatozoa with in vitro matured oocytes and (iii) In vitro culture (IVC) of zygotes up to the blastocyst stage. In vitro embryo production from oocytes recovered from prepubertal females is called JIVET (Juvenile in vitro Embryo Transfer) and allows shortened generation intervals and increased genetic gain. Embryo production together with embryo cryoconservation would allow large-scale embryo marketing, a pathogen-free genetic movement and easier and cheaper germplasm commercial transactions. Commercial Embryo activity in small ruminants is low compared to cows in the European Union (data from the European Embryo Transfer Association) and in the world (data from the International Embryo Transfer Association). There is less IVEP research in small ruminants compared to other livestock species. The aim of this review was to provide an overview of the current status of IVEP of small ruminant with an emphasis on (i) description of the main methodologies currently used for IVM, IVF and IVC of embryos (ii) comparing procedures and outputs from JIVET and IVEP of adult females and (iii) the future research perspectives of this technology.
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Affiliation(s)
- M-T Paramio
- Department of Animal and Food Sciences, University Autonomous of Barcelona, Barcelona, Spain
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Kim DH, No JG, Choi MK, Yeom DH, Kim DK, Yang BC, Yoo JG, Kim MK, Kim HT. In vitro development of canine somatic cell nuclear transfer embryos in different culture media. J Vet Sci 2014; 16:233-5. [PMID: 25549216 PMCID: PMC4483508 DOI: 10.4142/jvs.2015.16.2.233] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 11/06/2014] [Indexed: 11/20/2022] Open
Abstract
The objective of the present study was to investigate the effects of three different culture media on the development of canine somatic cell nuclear transfer (SCNT) embryos. Canine cloned embryos were cultured in modified synthetic oviductal fluid (mSOF), porcine zygote medium-3 (PZM-3), or G1/G2 sequential media. Our results showed that the G1/G2 media yielded significantly higher morula and blastocyst development in canine SCNT embryos (26.1% and 7.8%, respectively) compared to PZM-3 (8.5% and 0%or mSOF (2.3% and 0%) media. In conclusion, this study suggests that blastocysts can be produced more efficiently using G1/G2 media to culture canine SCNT embryos.
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Affiliation(s)
- Dong-Hoon Kim
- Division of Animal Biotechnology, National Institute of Animal Science, Rural Development Administration, Suwon 441-706,
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Absalón-Medina VA, Butler WR, Gilbert RO. Preimplantation embryo metabolism and culture systems: experience from domestic animals and clinical implications. J Assist Reprod Genet 2014; 31:393-409. [PMID: 24682781 PMCID: PMC3969471 DOI: 10.1007/s10815-014-0179-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 01/17/2014] [Indexed: 01/09/2023] Open
Abstract
Despite advantages of in vitro embryo production in many species, widespread use of this technology is limited by generally lower developmental competence of in vitro derived embryos compared to in vivo counterparts. Regardless, in vivo or in vitro gametes and embryos face and must adjust to multiple microenvironments especially at preimplantation stages. Moreover, the embryo has to be able to further adapt to environmental cues in utero to result in the birth of live and healthy offspring. Enormous strides have been made in understanding and meeting stage-specific requirements of preimplantation embryos, but interpretation of the data is made difficult due to the complexity of the wide array of culture systems and the remarkable plasticity of developing embryos that seem able to develop under a variety of conditions. Nevertheless, a primary objective remains meeting, as closely as possible, the preimplantation embryo requirements as provided in vivo. In general, oocytes and embryos develop more satisfactorily when cultured in groups. However, optimization of individual culture of oocytes and embryos is an important goal and area of intensive current research for both animal and human clinical application. Successful culture of individual embryos is of primary importance in order to avoid ovarian superstimulation and the associated physiological and psychological disadvantages for patients. This review emphasizes stage specific shifts in embryo metabolism and requirements and research to optimize in vitro embryo culture conditions and supplementation, with a view to optimizing embryo culture in general, and culture of single embryos in particular.
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Affiliation(s)
- V. A. Absalón-Medina
- Department of Animal Science, College of Agricultural Life Sciences, Cornell University, Ithaca, NY 14853 USA
| | - W. R. Butler
- Department of Animal Science, College of Agricultural Life Sciences, Cornell University, Ithaca, NY 14853 USA
| | - R. O. Gilbert
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853 USA
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de Souza-Fabjan JMG, Panneau B, Duffard N, Locatelli Y, de Figueiredo JR, Freitas VJDF, Mermillod P. In vitro production of small ruminant embryos: late improvements and further research. Theriogenology 2014; 81:1149-62. [PMID: 24650929 DOI: 10.1016/j.theriogenology.2014.02.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2013] [Revised: 01/28/2014] [Accepted: 02/01/2014] [Indexed: 10/25/2022]
Abstract
Beyond the potential use of in vitro production of embryos (IVP) in breeding schemes, embryos are also required for the establishment of new biotechnologies such as cloning and transgenesis. Additionally, the knowledge of oocyte and embryo physiology acquired through IVP techniques may stimulate the further development of other techniques such as marker assisted and genomic selection of preimplantation embryos, and also benefit assisted procreation in human beings. Efficient in vitro embryo production is currently a major objective for livestock industries, including small ruminants. The heterogeneity of oocytes collected from growing follicles by laparoscopic ovum pick up or in ovaries of slaughtered females, remains an enormous challenge for IVM success, and still limits the rate of embryo development. In addition, the lower quality of the IVP embryos, compared with their in vivo-derived counterparts, translates into poor cryosurvival, which restricts the wider use of this promising technology. Therefore, many studies have been reported in an attempt to determine the most suitable conditions for IVM, IVF, and in vitro development to maximize embryo production rate and quality. This review aims to present the current panorama of IVP production in small ruminants, describing important steps for its success, reporting the recent advances and also the main obstacles identified for its improvement and dissemination.
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Affiliation(s)
- Joanna Maria Gonçalves de Souza-Fabjan
- INRA, Physiologie de la Reproduction et des Comportements, Nouzilly, France; Faculty of Veterinary, Laboratory of Physiology and Control of Reproduction (LFCR), State University of Ceará, Fortaleza, Ceara, Brazil.
| | - Barbara Panneau
- INRA, Physiologie de la Reproduction et des Comportements, Nouzilly, France
| | - Nicolas Duffard
- INRA, Physiologie de la Reproduction et des Comportements, Nouzilly, France; Museum National d'Histoire Naturelle, Réserve de la Haute Touche, Obterre, France
| | - Yann Locatelli
- INRA, Physiologie de la Reproduction et des Comportements, Nouzilly, France; Museum National d'Histoire Naturelle, Réserve de la Haute Touche, Obterre, France
| | - José Ricardo de Figueiredo
- Faculty of Veterinary, Laboratory of Manipulation of Oocyte and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, Ceara, Brazil
| | | | - Pascal Mermillod
- INRA, Physiologie de la Reproduction et des Comportements, Nouzilly, France
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Abstract
The preference of fertilized (IVF) and somatic cell nuclear transfer (SCNT) presumptive zygotes for different media when cultured in vitro to the blastocyst stage was evaluated in this study. The experiment comprised two zygote production methods (IVF and SCNT) × two culture media (mSOF and G1.5/G2.5) factorial design in which culture droplets that contained approximate 30 presumptive zygotes formed the experimental plots for the assessment of cleavage and blastocyst development. There were 15 to 20 replicates (culture droplets) per treatment combination. Sub-samples 30 to 41 of the blastocysts produced were assessed for cell number and cell apoptosis. A further 10 blastocysts per treatment combination were used for quantitative real-time polymerase chain reaction (RT-PCR) to evaluate the relative abundance of Hsp70 and Bax mRNA. Presumptive zygotes produced by IVF were developmentally more competent than SCNT zygotes in terms of cleavage rate (66.9 vs. 57.0%; P < 0.05) and blastocyst development rates (blastocysts of presumptive zygotes 29.7 vs. 24.8%; blastocysts of cleaved zygotes 44.4 vs. 36.6%; P < 0.05). Over both zygote production systems, however, the results were similar whether culture was in mSOF or in G1.5/G2.5 media for cleavage rate (63.2 vs. 62.4%; P > 0.05) and blastocyst development rate (blastocysts of presumptive zygotes 26.4 vs. 25.7%; P > 0.05; blastocysts of cleaved zygotes 41.8 vs. 41.2%; P > 0.05). There was, however, a significant interaction between the method of zygote production and culture medium for the apoptotic index of blastocysts. The interaction was such that IVF-produced zygotes cultured in mSOF had a lower apoptotic index compared with those cultured in G1.5/G2.5 (4.7 ± 1.2% vs. 9.8 ± 0.9%; P < 0.05) whereas SCNT zygotes had a higher apoptotic index when cultured in mSOF compared with those cultured in G1.5/G2.5 (11.9 ± 1.5% vs. 4.5 ± 1.2%; P < 0.05). Moreover, RT-PCR analysis showed that embryos from IVF-produced zygotes cultured in mSOF had a lower expression level of stress-related and apoptosis genes (Hsp70 and Bax) than those cells cultured in G1.5/G2.5 medium, while SCNT-derived embryos cultured in mSOF had a higher expression level of these genes than those embryos cultured in G1.5/G2.5 medium. The results of this study show that bovine IVF- and SCNT-produced presumptive zygotes have different nutrient requirements for in vitro culture to the blastocyst stage of development. IVF-derived zygotes have a preference for mSOF as the culture medium whereas the G1.5/G2.5 medium is more suitable for the culture of bovine SCNT-derived zygotes.
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Wang YS, Tang S, An ZX, Li WZ, Liu J, Quan FS, Hua S, Zhang Y. Effect of mSOF and G1.1/G2.2 Media on the Developmental Competence of SCNT-Derived Bovine Embryos. Reprod Domest Anim 2011; 46:404-9. [DOI: 10.1111/j.1439-0531.2010.01679.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Tang S, Liu J, Du S, Li L, Zheng C, Zhao M, Wang Y, Zhang Y. Optimization of embryo culture conditions in the production of cloned goat embryos, following somatic cell nuclear transfer. Small Rumin Res 2011. [DOI: 10.1016/j.smallrumres.2010.11.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Wan PC, Hao ZD, Zhou P, Wu Y, Yang L, Cui MS, Liu SR, Zeng SM. Effects of SOF and CR1 media on developmental competence and cell apoptosis of ovine in vitro fertilization embryos. Anim Reprod Sci 2008; 114:279-88. [PMID: 19008058 DOI: 10.1016/j.anireprosci.2008.09.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2008] [Revised: 09/04/2008] [Accepted: 09/23/2008] [Indexed: 10/21/2022]
Abstract
The present study was to investigate effects of synthetic oviductal fluid (SOF) and Charles Rosenkrans medium (CR1) culture systems on developmental competence and cell apoptosis of ovine in vitro fertilization (IVF) embryos. Ovine presumptive IVF zygotes were cultured in the following six media: (1) SOF supplemented with amino acids (SOFaa) and 8 mg/ml bovine serum albumin (BSA) for 9 days (SOFaaBSA); (2) SOFaa supplemented with 10% fetal bovine serum (FBS) for 9 days (SOFaaFBS); (3) SOFaaBSA for first 3 days and then SOFaaFBS for later 6 days (SOFaaBSA-FBS); (4) CR1 supplemented with amino acids (CR1aa) and 8 mg/ml BSA for 9 days (CR1aaBSA); (5) CR1aa supplemented with 10% FBS for 9 days (CR1aaFBS); (6) CR1aaBSA for first 3 days and then CR1aaFBS for later 6 days (CR1aaBSA-FBS). The rates of blastocyst and hatched blastocyst in group 1, group 3 and group 6 were not different (P>0.05), but were greater than in other three groups (P<0.05). In SOF and CR1 cultural system, SOFaaBSA and CR1aaBSA-FBS provided the highest blastocyst rates respectively. Both numbers of total cell and trophectoderm (TE) in expanded or hatched blastocyst from SOFaaBSA were significantly higher than CR1aaBSA-FBS (P<0.05). However, the inner cell mass (ICM) cell number and ratio of ICM to TE cell in expanded or hatched blastocysts were not different between two groups (P>0.05). The apoptotic signals were firstly observed at 8-cell stage in two groups and became stronger and stronger with the development of embryos. Rates of embryos with apoptotic signals in group 6 at morula or blastocyst were greater than in group 1 (P<0.05). The apoptotic nuclei numbers of morula or blastocyst in group 6 were also significantly higher than group 1 (P<0.05). It is concluded that CR1aaBSA-FBS can support in vitro development of ovine IVF embryos, but SOFaaBSA is more suitable.
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Affiliation(s)
- Peng-cheng Wan
- Laboratory of Animal Embryonic Biotechnology, College of Animal Science and Technology, China Agricultural University, Beijing, PR China
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