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Agerholm JS, Madsen SE, Krogh AKH, Najafzadeh V, Secher JBM. Health assessment of Holstein calves born after in vitro fertilization, biopsy-based genotyping at the blastocyst stage and subsequent embryo transfer. Theriogenology 2023; 211:76-83. [PMID: 37595376 DOI: 10.1016/j.theriogenology.2023.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 08/07/2023] [Accepted: 08/07/2023] [Indexed: 08/20/2023]
Abstract
Establishing methods for evaluating genomic estimated breeding values of bovine embryos can potentially increase the efficiency of breeding programs by transferring only embryos with a high genomic estimated breeding value. This may be achieved by analyzing DNA from trophectoderm biopsies. However, manipulation of bovine embryos is associated with a risk of impaired conceptus health. More knowledge on the health implications of embryonic handling procedures is required. In this study, we followed pregnancies after transfer of in vitro-produced (IVP) embryos and assessed the health of the offspring during the first 2 weeks of life. Three groups of calves were studied: i) freshly transferred non-biopsied embryos (39 transfers, 17 calves; Group B-/C-); ii) biopsied and freshly transferred IVP embryos (42 transfers, 21 calves; Group B+/C-); iii) biopsied and cryopreserved IVP embryos (17 transfers, 6 calves; Group B+/C+). Blood biochemical and hematologic values were compared between groups and to a control group of 13 calves produced by conventional artificial insemination. The pregnancy rate on day 50 and the calving rate did not differ among the groups, but the average gestation length of the B+/C+ group was significantly shorter and with wider variation than the two other groups. There was a tendency toward a higher average body weight at birth in group B+/C+ (45.1 kg) and the standard deviation in body weight was larger (11.7 kg) compared to the B-/C- (39.5 kg; 3.2 kg) and B+/C- (41.8 kg; 6 kg) groups. Body weight on day 14 was higher in the B+/C+ calves compared to the other groups. There was no difference in the biochemical and hematological values at birth between the groups and these were within the normal range. However, when compared to a group of calves produced by standard artificial insemination, significantly higher concentrations were found for the hepatic-related enzymes ALAT, ASAT, ALP, and GGT in group B-/C-and B+/C-, while only higher ALP concentrations were found in B+/C+ calves. The biochemical findings indicate higher heterogeneity in IVP calves compared to calves produced by artificial insemination. The more manipulated IVP embryos also showed increased heterogeneity in body weight at birth, with a shift toward heavier calves, which calls for closer attendance at parturition to handle dystocia in a timely manner and minimize fetal losses.
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Affiliation(s)
- Jørgen Steen Agerholm
- Section for Veterinary Reproduction and Obstetrics, Department of Veterinary Clinical Sciences, University of Copenhagen, Højbakkegaard Allé 5A, 2630, Taastrup, Denmark.
| | | | - Anne Kirstine Havnsøe Krogh
- Section for Medicine, Oncology and Veterinary Clinical Pathology, Department of Veterinary Clinical Sciences, University of Copenhagen, Dyrlægevej 16, 1870, Frederiksberg C, Denmark.
| | - Vahid Najafzadeh
- Department of Veterinary and Animal Sciences, University of Copenhagen, 1870, Frederiksberg C, Denmark.
| | - Jan Bojsen-Møller Secher
- Section for Veterinary Reproduction and Obstetrics, Department of Veterinary Clinical Sciences, University of Copenhagen, Højbakkegaard Allé 5A, 2630, Taastrup, Denmark.
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Oliveira CS, Camargo LSA, da Silva MVGB, Saraiva NZ, Quintão CC, Machado MA. Embryo biopsies for genomic selection in tropical dairy cattle. Anim Reprod 2023; 20:e20230064. [PMID: 37547565 PMCID: PMC10399131 DOI: 10.1590/1984-3143-ar2023-0064] [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: 05/02/2023] [Accepted: 06/21/2023] [Indexed: 08/08/2023] Open
Abstract
Genomic selection has transformed the livestock industry, enabling early-life selection of animals. Biopsy sampling of pre-implantation embryos has been described since 1968. However, it was only after 2010, with the advancement of molecular biology techniques such as whole genomic amplification and SNP Chips, that next-generation sequencing became commercially available for bovine embryos. It is now possible to make decisions about which embryos to transfer not only based on recipients' availability or embryo morphology but also on genomic estimates. This technology can be implemented for a wide spectrum of applications in livestock. In this review, we discuss the use of embryo biopsy for genomic selection and share our experience with Gir and Girolando Brazilian breeding programs, as well as future goals for implementing it in Brazilian bovine in vitro embryo production practices.
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Embryo sexing methods in bovine and its application in animal breed. JOURNAL OF ANIMAL REPRODUCTION AND BIOTECHNOLOGY 2022. [DOI: 10.12750/jarb.37.2.80] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Fujii T, Hirayama H, Naito A, Kashima M, Sakai H, Fukuda S, Yoshino H, Moriyasu S, Kageyama S, Sugimoto Y, Matsuyama S, Hayakawa H, Kimura K. Production of calves by the transfer of cryopreserved bovine elongating conceptuses and possible application for preimplantation genomic selection. J Reprod Dev 2017; 63:497-504. [PMID: 28781338 PMCID: PMC5649099 DOI: 10.1262/jrd.2017-025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Preimplantation genomic selection based on single nucleotide polymorphism (SNP) genotypes is expected to accelerate genetic improvement in cattle. However, genome-wide genotyping at the early embryonic stage has several limitations, such as the technical difficulty of embryonic biopsy and low accuracy of genotyping resulting from a limited number of biopsied cells. After hatching from the zona pellucida, the morphology of the bovine embryo changes from spherical to filamentous, in a process known as elongation. The bovine nonsurgical elongating conceptus transfer technique was recently developed and applied for sexing without requiring specialized skills for biopsy. In order to develop a bovine preimplantation genomic selection system combined with the elongating conceptus transfer technique, we examined the accuracy of genotyping by SNP chip analysis using the DNA from elongating conceptuses (Experiment 1) and optimal cryopreservation methods for elongating conceptuses (Experiment 2). In Experiment 1, the call rates of SNP chip analysis following whole genome amplification in biopsied cells from two elongating conceptuses were 95.14% and 99.32%, which were sufficient for estimating genomic breeding value. In Experiment 2, the rates of dead cells in elongating conceptuses cryopreserved by slow freezing were comparable to those in fresh elongating conceptuses. In addition, we obtained healthy calves by the transfer of elongating conceptuses cryopreserved by slow freezing. Our findings indicate that the elongating conceptus transfer technology enables preimplantation genomic selection in cattle based on SNP chip analysis. Further studies on the optimization of cryopreservation methods for elongating conceptuses are required for practical application of the selection system.
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Affiliation(s)
- Takashi Fujii
- Animal Biotechnology Group, Animal Research center, Hokkaido Research Organization, Hokkaido 081-0038, Japan
| | - Hiroki Hirayama
- Animal Biotechnology Group, Animal Research center, Hokkaido Research Organization, Hokkaido 081-0038, Japan.,Department of Bioproduction, Faculty of Bioindustry, Tokyo University of Agriculture, Hokkaido 099-2493, Japan
| | - Akira Naito
- Animal Biotechnology Group, Animal Research center, Hokkaido Research Organization, Hokkaido 081-0038, Japan
| | - Masashi Kashima
- Animal Biotechnology Group, Animal Research center, Hokkaido Research Organization, Hokkaido 081-0038, Japan
| | - Hitomi Sakai
- Department of Bioproduction, Faculty of Bioindustry, Tokyo University of Agriculture, Hokkaido 099-2493, Japan
| | - Shigeo Fukuda
- Animal Biotechnology Group, Animal Research center, Hokkaido Research Organization, Hokkaido 081-0038, Japan
| | - Hitomi Yoshino
- Animal Biotechnology Group, Animal Research center, Hokkaido Research Organization, Hokkaido 081-0038, Japan
| | - Satoru Moriyasu
- Animal Biotechnology Group, Animal Research center, Hokkaido Research Organization, Hokkaido 081-0038, Japan
| | - Soichi Kageyama
- Animal Biotechnology Group, Animal Research center, Hokkaido Research Organization, Hokkaido 081-0038, Japan
| | - Yoshikazu Sugimoto
- Shirakawa Institute of Animal Genetics, Japan Livestock Technology Association, Fukushima 961-8061, Japan
| | - Shuichi Matsuyama
- Animal Feeding and Management Research Division, NARO Institute of Livestock and Grassland Science, Tochigi 329-2793, Japan
| | | | - Koji Kimura
- Graduate School of Environmental and Life Science, Okayama University, Okayama 700-8530, Japan
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de Sousa RV, da Silva Cardoso CR, Butzke G, Dode MAN, Rumpf R, Franco MM. Biopsy of bovine embryos produced in vivo and in vitro does not affect pregnancy rates. Theriogenology 2017; 90:25-31. [DOI: 10.1016/j.theriogenology.2016.11.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 10/27/2016] [Accepted: 11/02/2016] [Indexed: 01/28/2023]
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6
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Maglorius Renkilaraj MRL, Baudouin L, Wells CM, Doulazmi M, Wehrlé R, Cannaya V, Bachelin C, Barnier JV, Jia Z, Nait Oumesmar B, Dusart I, Bouslama-Oueghlani L. The intellectual disability protein PAK3 regulates oligodendrocyte precursor cell differentiation. Neurobiol Dis 2016; 98:137-148. [PMID: 27940202 DOI: 10.1016/j.nbd.2016.12.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 11/04/2016] [Accepted: 12/02/2016] [Indexed: 10/20/2022] Open
Abstract
Oligodendrocyte and myelin deficits have been reported in mental/psychiatric diseases. The p21-activated kinase 3 (PAK3), a serine/threonine kinase, whose activity is stimulated by the binding of active Rac and Cdc42 GTPases is affected in these pathologies. Indeed, many mutations of Pak3 gene have been described in non-syndromic intellectual disability diseases. Pak3 is expressed mainly in the brain where its role has been investigated in neurons but not in glial cells. Here, we showed that PAK3 is highly expressed in oligodendrocyte precursors (OPCs) and its expression decreases in mature oligodendrocytes. In the developing white matter of the Pak3 knockout mice, we found defects of oligodendrocyte differentiation in the corpus callosum and to a lesser extent in the anterior commissure, which were compensated at the adult stage. In vitro experiments in OPC cultures, derived from Pak3 knockout and wild type brains, support a developmental and cell-autonomous role for PAK3 in regulating OPC differentiation into mature oligodendrocytes. Moreover, we did not detect any obvious alterations of the proliferation or migration of Pak3 null OPCs compared to wild type. Overall, our data highlight PAK3 as a new regulator of OPC differentiation.
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Affiliation(s)
| | - Lucas Baudouin
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinière, F-75013 Paris, France
| | | | - Mohamed Doulazmi
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Adaptation Biologique et vieillissement, F-75005 Paris, France
| | - Rosine Wehrlé
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, F-75005 Paris, France
| | - Vidjeacoumary Cannaya
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, F-75005 Paris, France
| | - Corinne Bachelin
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinière, F-75013 Paris, France
| | - Jean-Vianney Barnier
- Institute of Neuroscience Paris-Saclay, CNRS-Université Paris-Sud, UMR9197, F-91405 Orsay, France
| | - Zhengping Jia
- Neurosciences & Mental Health, The Hospital for Sick Children, and Department of Physiology, Faculty of Medicine, University of Toronto, 555 University, Toronto, Ontario M5G 1X8, Canada
| | - Brahim Nait Oumesmar
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinière, F-75013 Paris, France
| | - Isabelle Dusart
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, F-75005 Paris, France
| | - Lamia Bouslama-Oueghlani
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, F-75005 Paris, France; Sorbonne Universités, UPMC Univ Paris 06, INSERM U 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinière, F-75013 Paris, France.
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TAŞKIN AC, AKKOÇ T, SAĞIRKAYA H, BAĞIŞ H, ARAT S. Comparison of the development of mouse embryos manipulatedwith different biopsy techniques. TURKISH JOURNAL OF VETERINARY & ANIMAL SCIENCES 2016. [DOI: 10.3906/vet-1506-63] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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8
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Ponsart C, Le Bourhis D, Knijn H, Fritz S, Guyader-Joly C, Otter T, Lacaze S, Charreaux F, Schibler L, Dupassieux D, Mullaart E. Reproductive technologies and genomic selection in dairy cattle. Reprod Fertil Dev 2014; 26:12-21. [PMID: 24305173 DOI: 10.1071/rd13328] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Genomic tools are now available for most livestock species and are used routinely for genomic selection (GS) in cattle. One of the most important developments resulting from the introduction of genomic testing for dairy cattle is the application of reasonably priced low-density single nucleotide polymorphism technology in the selection of females. In this context, combining genome testing and reproductive biotechnologies in young heifers enables new strategies to generate replacement and elite females in a given period of time. Moreover, multiple markers have been detected in biopsies of preimplantation stage embryos, thus paving the way to develop new strategies based on preimplantation diagnosis and the genetic screening of embryos. Based on recent advances in GS, the present review focuses on new possibilities inherent in reproductive technologies used for commercial purposes and in genetic schemes, possible side effects and beneficial impacts on reproductive efficiency. A particular focus is on the different steps allowing embryo genotyping, including embryo micromanipulation, DNA production and quality assessment.
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Affiliation(s)
- C Ponsart
- UNCEIA Research and Development, 13 rue Jouet, 94704 Maisons Alfort, France
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Ramos-Ibeas P, Calle A, Pericuesta E, Laguna-Barraza R, Moros-Mora R, Lopera-Vásquez R, Maillo V, Yáñez-Mó M, Gutiérrez-Adán A, Rizos D, Ramírez MÁ. An efficient system to establish biopsy-derived trophoblastic cell lines from bovine embryos. Biol Reprod 2014; 91:15. [PMID: 24855108 DOI: 10.1095/biolreprod.114.118430] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Trophoblastic cells play a crucial role in implantation and placentogenesis and can be used as a model to provide substantial information on the peri-implantation period. Unfortunately, there are few cell lines for this purpose in cattle because of the difficulty of raising successive cell stocks in the long-term. Our results show that the combination of a monolayer culture system in microdrops on a surface treated with gelatin and the employment of conditioned media from mouse embryonic fibroblasts support the growth of bovine trophoblastic cells lines from an embryo biopsy. Expression profiles of mononucleate- and binucleate-specific genes in established trophoblastic cells lines represented various stages of gestation. Moreover, the ability to expand trophoblastic cell lines for more than 2 yr together with pluripotency-related gene expression patterns revealed certain self-renewal capacity. In summary, we have developed a system to expand in vitro trophoblastic cells from an embryo biopsy that solves the limitations of using amplified DNA from a small number of cells for bovine embryo genotyping and epigenotyping and, on the other hand, facilitates the establishment of trophoblastic cell lines that can be useful as peri-implantation in vitro models.
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Affiliation(s)
| | | | - Eva Pericuesta
- Departamento de Reproduccion Animal, INIA, Madrid, Spain
| | | | | | | | | | - María Yáñez-Mó
- Hospital Universitario Santa Cristina, Instituto de Investigaciones Sanitarias Princesa, Madrid, Spain
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Abstract
Three recent breakthroughs have resulted in the current widespread use of DNA information: the genomic selection (GS) methodology, which is a form of marker-assisted selection on a genome-wide scale, and the discovery of large numbers of single-nucleotide markers and cost effective methods to genotype them. GS estimates the effect of thousands of DNA markers simultaneously. Nonlinear estimation methods yield higher accuracy, especially for traits with major genes. The marker effects are estimated in a genotyped and phenotyped training population and are used for the estimation of breeding values of selection candidates by combining their genotypes with the estimated marker effects. The benefits of GS are greatest when selection is for traits that are not themselves recorded on the selection candidates before they can be selected. In the future, genome sequence data may replace SNP genotypes as markers. This could increase GS accuracy because the causative mutations should be included in the data.
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Affiliation(s)
- Theo Meuwissen
- Department of Animal and Aquaculture Sciences, Norwegian University of Life Sciences, Aas, Norway 1430;
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Machaty Z, Peippo J, Peter A. Production and manipulation of bovine embryos: Techniques and terminology. Theriogenology 2012; 78:937-50. [DOI: 10.1016/j.theriogenology.2012.04.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 04/06/2012] [Accepted: 04/06/2012] [Indexed: 10/28/2022]
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12
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Korhonen K, Julkunen H, Kananen K, Bredbacka P, Tiirikka T, Räty M, Vartia K, Kaimio I, Kontinen A, Halmekytö M, Vilkki J, Peippo J, Lindeberg H. The effect of ascorbic acid during biopsy and cryopreservation on viability of bovine embryos produced in vivo. Theriogenology 2012; 77:201-5. [DOI: 10.1016/j.theriogenology.2011.07.034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 07/05/2011] [Accepted: 07/25/2011] [Indexed: 11/16/2022]
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13
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Guignot F, Perreau C, Cavarroc C, Touzé JL, Pougnard JL, Dupont F, Beckers JF, Rémy B, Babilliot JM, Bed’Hom B, Lamorinière JM, Mermillod P, Baril G. Sex and PRNP Genotype Determination in Preimplantation Caprine Embryos. Reprod Domest Anim 2010; 46:656-63. [DOI: 10.1111/j.1439-0531.2010.01724.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Humblot P, Le Bourhis D, Fritz S, Colleau JJ, Gonzalez C, Guyader Joly C, Malafosse A, Heyman Y, Amigues Y, Tissier M, Ponsart C. Reproductive technologies and genomic selection in cattle. Vet Med Int 2010; 2010:192787. [PMID: 20981298 PMCID: PMC2963139 DOI: 10.4061/2010/192787] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Accepted: 09/23/2010] [Indexed: 12/02/2022] Open
Abstract
The recent development of genomic selection induces dramatic changes in the way genetic selection schemes are to be conducted. This review describes the new context and corresponding needs for genomic based selection schemes and how reproductive technologies can be used to meet those needs. Information brought by reproductive physiology will provide new markers and new improved phenotypes that will increase the efficiency of selection schemes for reproductive traits. In this context, the value of the reproductive techniques including assisted embryo based reproductive technologies (Multiple Ovaluation Embryo Transfer and Ovum pick up associated to in vitro Fertilization) is also revisited. The interest of embryo typing is discussed. The recent results obtained with this emerging technology which are compatible with the use of the last generation of chips for genotype analysis may lead to very promising applications for the breeding industry. The combined use of several embryo based reproductive technologies will probably be more important in the near future to satisfy the needs of genomic selection for increasing the number of candidates and to preserve at the same time genetic variability.
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Affiliation(s)
- Patrice Humblot
- UNCEIA, Department of Research and Development, 13 rue Jouet, 94704 Maisons Alfort, France
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Miltiadou D, Tzamaloukas O, Genethliou N, Papachristoforou C, Chatziplis D, Orford M. Do established SNPs affecting bovine milk traits exist in other dairy ruminants? Small Rumin Res 2010. [DOI: 10.1016/j.smallrumres.2009.11.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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16
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Guignot F, Baril G, Dupont F, Cognie Y, Folch J, Alabart JL, Poulin N, Beckers JF, Bed'hom B, Babilliot JM, Mermillod P. Determination of sex and scrapie resistance genotype in preimplantation ovine embryos. Mol Reprod Dev 2009; 76:183-90. [PMID: 18543282 DOI: 10.1002/mrd.20940] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The aim of this study was to test the accuracy of genotype diagnosis after pre-amplification of DNA extracted from biopsies obtained by microblade cutting of ovine embryos and to evaluate the viability of biopsied embryos after vitrification/warming and transfer to recipients. Sex and PrP genotypes were determined. Sex diagnosis was done by PCR amplification of ZFX/ZFY and SRY sequences after PEP-PCR while PrP genotype determination was performed after specific pre-amplification of specific target including codons 136, 154 and 171. Embryos were collected at Day 7 after oestrus. Blastocysts and expanded blastocysts were biopsied immediately after collection whereas compacted morulae were biopsied after 24 hr of in vitro culture. Eighty-nine biopsied embryos were frozen by vitrification. Fresh and vitrified whole embryos were kept as control. DNA of biopsies was extracted and pre-amplified. Sex diagnosis was efficient for 96.6% of biopsies and PrP genotyping was determined in 95.8% of codons. After embryo transfer, no significant difference was observed in lambing rate between biopsied, vitrified control and fresh embryos (54.5%, 60% and 66.6%, respectively). Embryo survival rate was not different between biopsied and whole vitrified embryos (P = 0.38). At birth, 96.7% of diagnosed sex and 95.4% of predetermined codons were correct. Lamb PrP profiles were in agreement with parental genotype. PEP-PCR coupled with sex diagnosis and nested PCR coupled with PrP genotype predetermination are very accurate techniques to genotype ovine embryo before transfer. These original results allow planning of selection of resistant genotype to scrapie and sex of offspring before transfer of cryopreserved embryo.
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Affiliation(s)
- Florence Guignot
- UMR INRA-CNRS-Université de Tours-Haras Nationaux, Physiologie de la Reproduction et des Comportements, Nouzilly, France.
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