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Gangwar L, Phatak SS, Etheridge M, Bischof JC. A guide to successful mL to L scale vitrification and rewarming. CRYO LETTERS 2022; 43:316-321. [PMID: 36629824 PMCID: PMC10217567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Cryopreservation by vitrification to achieve an "ice free" glassy state is an effective technique for preserving biomaterials including cells, tissues, and potentially even whole organs. The major challenges in cooling to and rewarming from a vitrified state remain ice crystallization and cracking/fracture. Ice crystallization can be inhibited by the use of cryoprotective agents (CPAs), though the inhibition further depends upon the rates achieved during cooling and rewarming. The minimal rate required to prevent any ice crystallization or recrystallization/devitrification in a given CPA is called the critical cooling rate (CCR) or critical warming rate (CWR), respectively. On the other hand, physical cracking is mainly related to thermomechanical stresses, which can be avoided by maintaining temperature differences below a critical threshold. In this simplified analysis, we calculate deltaT as the largest temperature difference occurring in a system during cooling or rewarming in the brittle/glassy phase. This deltaT is then used in a simple "thermal shock equation" to estimate thermal stress within the material to decide if the material is above the yield strength and to evaluate the potential for fracture failure. In this review we aimed to understand the limits of success and failure at different length scales for cryopreservation by vitrification, due to both ice crystallization and cracking. Here we use thermal modeling to help us understand the magnitude and trajectory of these challenges as we scale the biomaterial volume for a given CPA from the milliliter to liter scale. First, we solved the governing heat transfer equations in a cylindrical geometry for three common vitrification cocktails (i.e., VS55, DP6, and M22) to estimate the cooling and warming rates during convective cooling and warming and nanowarming (volumetric heating). Second, we estimated the temperature difference deltaT and compared it to a tolerable threshold (deltaTmax) based on a simplified "thermal shock" equation for the same cooling and rewarming conditions. We found, not surprisingly, that M22 achieves vitrification more easily during convective cooling and rewarming for all volumes compared to VS55 or DP6 due to its considerably lower CCR and CWR. Further, convective rewarming (boundary rewarming) leads to larger temperature differences and smaller rates compared to nanowarming (volumetric rewarming) for all CPAs with increasing failure at larger volumes. We conclude that as more and larger systems are vitrified and rewarmed with standard CPA cocktails, this work can serve as a practical guide to successful implementation based on the characteristic length (volume/surface area) of the system and the specific conditions of cooling and warming. doi.org/10.54680/fr22610110112.
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Affiliation(s)
- L Gangwar
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, 55455 USA
| | - S S Phatak
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, 55455 USA
| | - M Etheridge
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, 55455 USA
| | - J C Bischof
- Department of Mechanical Engineering; Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, 55455 USA.
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Gangwar L, Phatak SS, Etheridge M, Bischof JC. Perspective: A Guide to Successful ml to L Scale Vitrification and Rewarming. CRYOLETTERS 2022. [DOI: 10.54680/fr22610110112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Cryopreservation by vitrification to achieve an "ice free" glassy state is an effective technique for preserving biomaterials including cells, tissues, and potentially even whole organs. The major challenges in cooling to and rewarming from a vitrified state remain ice crystallization
and cracking/fracture. Ice crystallization can be inhibited by the use of cryoprotective agents (CPAs), though the inhibition further depends upon the rates achieved during cooling and rewarming. The minimal rate required to prevent any ice crystallization or recrystallization/devitrification
in a given CPA is called the critical cooling rate (CCR) or critical warming rate (CWR), respectively. On the other hand, physical cracking is mainly related to thermomechanical stresses, which can be avoided by maintaining temperature differences below a critical threshold. In this simplified
analysis, we calculate ΔT as the largest temperature difference occurring in a system during cooling or rewarming in the brittle/glassy phase. This ΔT is then used in a simple "thermal shock equation" to estimate thermal stress within the material to decide if the material is above
the yield strength and to evaluate the potential for fracture failure. In this review we aimed to understand the limits of success and failure at different length scales for cryopreservation by vitrification, due to both ice crystallization and cracking. Here we use thermal modeling to help
us understand the magnitude and trajectory of these challenges as we scale the biomaterial volume for a given CPA from the milliliter to liter scale. First, we solved the governing heat transfer equations in a cylindrical geometry for three common vitrification cocktails (i. e., VS55, DP6,
and M22) to estimate the cooling and warming rates during convective cooling and warming and nanowarming (volumetric heating). Second, we estimated the temperature difference (ΔT) an d compared it to a tolerable threshold ( ΔTmax) based on a simplified "thermal shock" equation
for the same cooling and rewarming conditions . We found, not surprisingly, that M22 achieves vitrification more easily during convective cooling and rewarming for all volumes compared to VS55 or DP6 due to its considerably lower CCR and CWR. Further, convective rewarming (boundary rewarming)
leads to larger temperature differences and smaller rates compared to nanowarming (volumetric rewarming) for all CPAs with increasing failure at larger volumes. We conclude that as more and larger systems are vitrified and rewarmed with standard CPA cocktails, this work can serve as a practical
guide to successful implementation based on the characteristic length (volume/surface area) of the system and the specific conditions of cooling and warming.
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Affiliation(s)
- Lakshya Gangwar
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, 55455 USA
| | - Shaunak S. Phatak
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, 55455 USA
| | - Michael Etheridge
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, 55455 USA
| | - John C. Bischof
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, 55455 USA
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Suttirojpattana T, Juanpanich T, Parnpai R, Vutyavanich T. Vitrification of mouse two-cell and blastocyst stage embryos in simplified closed system using either a hemi-straw or a hollow fiber device. Anim Sci J 2021; 92:e13585. [PMID: 34231952 DOI: 10.1111/asj.13585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 05/20/2021] [Accepted: 05/31/2021] [Indexed: 11/27/2022]
Abstract
Two-cell stage and blastocyst stage mouse embryos were equilibrated in a medium containing 7.5% ethylene glycol (EG) and 7.5% dimethyl sulfoxide (DMSO) for 8-15 min. Vitrification was performed in a medium containing 0.5 M sucrose and either 15% EG + 15% DMSO, 17.5% EG + 17.5% DMSO, or 20% EG + 20% DMSO for 30 s. They were then placed either on a hemi-straw (HS) or a hollow fiber vitrification (HFV) device and vitrified by cooled air inside a 0.5-ml straw. In two-cell embryos, a 100% survival rate was obtained from all groups except the 20% HS group (P > .05). All vitrified two-cell groups showed similar rates of blastocyst development to that of fresh control group (P > .05), except 17.5% and 20% HFV groups, which were significantly lower than the other groups (P < .05). In the blastocyst embryos, the HFV groups were divided into two subgroups (non-collapsed; HFV-NC and collapsed; HFV-C blastocyst). Re-expansion rate in 15% HFV-NC, 17.5% HFV-NC, and 15% HFV-C groups was reduced (P < .05), whereas the rest were similar to control. In conclusion, we established a simplified, reliable, and closed system for HFV vitrification applying hemi-straw, which does not require skilled practitioners.
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Affiliation(s)
| | | | - Rangsun Parnpai
- Embryo Technology and Stem Cell Research Center, School of Biotechnology, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Teraporn Vutyavanich
- Division of Reproductive Medicine, Department of Obstetrics and Gynecology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
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Rahiminia T, Hosseini A, Anvari M, Ghasemi-Esmailabad S, Talebi AR. Modern human sperm freezing: Effect on DNA, chromatin and acrosome integrity. Taiwan J Obstet Gynecol 2018; 56:472-476. [PMID: 28805603 DOI: 10.1016/j.tjog.2017.02.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/24/2017] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVE Presence of vitrification method in sperm freezing and the introduction of solid surface vitrification beside rapid freezing in vapour, opens an easy and safe way to help infertility centres. While the effects of cryopreservation on motility, morphology and viability of sperm are documented, the question of the probable alteration of sperm DNA, chromatin and acrosome integrity after freezing and thawing procedures in different methods is still controversial. MATERIALS AND METHODS Normal sample were collected according to WHO strict criteria. Sperm suspensions were mixed 1:1 with 0.5 M sucrose and divided into four equal aliquots for freezing: fresh, nitrogen direct immersion vitrification (Vit), solid surface vitrification (SSV) and in vapour (Vapour). Sperm suspensions were transferred into a 0.25 ml sterile plastic. Then straw was inserted inside the 0.5 ml straw. For thawing, the straws were immersed in a 42 °C water bath. Beside the sperm parameters, we assessed the acrosome reaction by double staining, chromatin integrity by toluidine blue (Tb) and chromomycin A3 (CMA3) and DNA integrity by terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) respectively. RESULTS In progressive motility, the highest rate occurred in Vit (39.9 ± 13.3). Moreover, the lowest rate of immotile sperm was in Vit (32.7 ± 16.3). In normal morphology, the group Vit was similar to the fresh, while SSV and Vapour were significantly different from the fresh. The percentage of acrosome-reacted sperms was more in Vit (81.3 ± 10.2) than the fresh group. TUNEL+ results showed that DNA fragmentation was significantly increased in Vit (p-value = 0.025). While in SSV and Vapour results were comparable to fresh. There was a significant correlation between TUNEL+ and normal morphology, TB, CMA3 and presence of intact acrosome. CONCLUSION Sperm in Vapour was healthier in terms of DNA, chromatin and acrosome integrity. In contrast of higher motility and normal morphology; DNA, chromatin and acrosome integrity were decreased in Vit. However, these findings were more acceptable in SSV or Vapour.
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Affiliation(s)
- Tahereh Rahiminia
- Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, 999-89195, Iran.
| | - Akram Hosseini
- Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, 999-89195, Iran.
| | - Morteza Anvari
- Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, 999-89195, Iran.
| | - Saeed Ghasemi-Esmailabad
- Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, 999-89195, Iran.
| | - Ali Reza Talebi
- Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, 999-89195, Iran.
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Teixeira M, Buff S, Desnos H, Loiseau C, Bruyère P, Joly T, Commin L. Ice nucleating agents allow embryo freezing without manual seeding. Theriogenology 2017; 104:173-178. [PMID: 28863350 DOI: 10.1016/j.theriogenology.2017.08.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 07/28/2017] [Accepted: 08/10/2017] [Indexed: 11/17/2022]
Abstract
Embryo slow freezing protocols include a nucleation induction step called manual seeding. This step is time consuming, manipulator dependent and hard to standardize. It requires access to samples, which is not always possible within the configuration of systems, such as differential scanning calorimeters or cryomicroscopes. Ice nucleation can be induced by other methods, e.g., by the use of ice nucleating agents. Snomax is a commercial preparation of inactivated proteins extracted from Pseudomonas syringae. The aim of our study was to investigate if Snomax can be an alternative to manual seeding in the slow freezing of mouse embryos. The influence of Snomax on the pH and osmolality of the freezing medium was evaluated. In vitro development (blastocyst formation and hatching rates) of fresh embryos exposed to Snomax and embryo cryopreserved with and without Snomax was assessed. The mitochondrial activity of frozen-thawed blastocysts was assessed by JC-1 fluorescent staining. Snomax didn't alter the physicochemical properties of the freezing medium, and did not affect embryo development of fresh embryos. After cryopreservation, the substitution of manual seeding by the ice nucleating agent (INA) Snomax did not affect embryo development or embryo mitochondrial activity. In conclusion, Snomax seems to be an effective ice nucleating agent for the slow freezing of mouse embryos. Snomax can also be a valuable alternative to manual seeding in research protocols in which manual seeding cannot be performed (i.e., differential scanning calorimetry and cryomicroscopy).
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Affiliation(s)
| | - Samuel Buff
- Univ Lyon, VetAgro Sup, Marcy l'Etoile, France
| | - Hugo Desnos
- Univ Lyon, VetAgro Sup, Marcy l'Etoile, France; Press Sorbonne Paris-Cité, Université Paris Descartes, Paris, France
| | | | | | - Thierry Joly
- Univ Lyon, VetAgro Sup, Marcy l'Etoile, France; Univ Lyon, ISARA-Lyon, Lyon, France
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Effect of cryopreservation technique and season on the survival of in vitro produced cattle embryos. Anim Reprod Sci 2015; 164:162-8. [PMID: 26679433 DOI: 10.1016/j.anireprosci.2015.11.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 11/26/2015] [Accepted: 11/30/2015] [Indexed: 12/31/2022]
Abstract
Embryo cryopreservation is a major tool for conservation and propagation of genetically superior animals. However, it adversely affects the survival of embryos. The objective of this study was to determine the effects of cryopreservation technique (vitrification compared with slow freezing) and different seasons in which oocytes were obtained on the post-warming survival of in vitro produced (IVP) cattle morulae. In experiment 1, morulae (Day 6 post-IVF), obtained from abattoir-sourced oocytes during spring, summer, fall and winter over a period of 3.5 years, were subjected to either vitrification (n=271 morulae), slow freezing (n=281 morulae) or no freezing (control; n=249 morulae). After warming, the morulae were cultured to the expanded blastocyst stage (Day 8 post-IVF). Data were compared using Glimmix procedure in SAS(®). Blastocyst rate differed (P<0.05) among the treatments: unfrozen control (78±3.6%), vitrification (52±4.6%) and slow freezing (35±4.2%). The re-expansion of vitrified morulae upon warming was not correlated with subsequent blastocyst rate (r=-0.048; P>0.05). The morulae produced during fall season had lesser (P<0.05) cleavage and morula rates (67±1.6%; Day 2 post-IVF and 22±1.4%; Day 6 post-IVF, respectively) than all other seasons (74±1.1 and 30±1.2%, respectively). Blastocyst rate was the least (P<0.05) when oocytes were collected during the summer season in both control and slowly frozen groups. Blastocyst development rate did not change due to season in vitrification group (P>0.05). In conclusion, vitrification is a more desirable technique than slow freezing for cryopreservation of IVP cattle morulae. If the slow freezing method is employed, greater success can be achieved using oocytes collected in the winter and spring with a primary contributing factor being lesser morulae development if oocytes are collected in the fall and also the lesser blastocyst formation of cryopreserved morulae when oocytes are collected in the summer.
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Somoskoi B, Martino NA, Cardone RA, Lacalandra GM, Dell'Aquila ME, Cseh S. Different chromatin and energy/redox responses of mouse morulae and blastocysts to slow freezing and vitrification. Reprod Biol Endocrinol 2015; 13:22. [PMID: 25889099 PMCID: PMC4419566 DOI: 10.1186/s12958-015-0018-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 03/09/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The ability to cryopreserve mammalian embryos has become an integral part of assisted reproduction, both in human and veterinary medicine. Despite differences in the size and physiological characteristics of embryos from various species, the embryos have been frozen by either of two procedures: slow freezing or vitrification. The aim of our study was to compare the effect of slow freezing and vitrification to the chromatin structure, energy status and reactive oxygen species production of mouse morulae and blastocysts. METHODS Mouse morulae and blastocysts were randomly allocated into vitrification, slow freezing and control groups. For slow freezing, Dulbecco phosphate buffered saline based 10% glicerol solution was used. For vitrification, G-MOPS™ based solution supplemented with 16% ethylene glycol, 16% propylene glycol, Ficoll (10 mg/ml) and sucrose (0.65 mol/l) was used. After warming, the chromatin integrity, mitochondrial distribution pattern and energy/oxidative status were compared among groups. RESULTS Cryopreservation affected chromatin integrity at a greater extent at the morula than the blastocyst stage. Chromatin damage induced by slow freezing was more relevant compared to vitrification. Slow freezing and vitrification similarly affected mitochondrial distribution pattern. Greater damage was observed at the morula stage and it was associated with embryo grade. Cryopreservation altered the quantitative bioenergy/redox parameters at a greater extent in the morulae than in the blastocysts. Effects induced by slow freezing were not related to embryo grade or mitochondrial pattern, as affected embryos were of all grades and with both mitochondrial patterns. However, effects induced by vitrification were related to mitochondrial pattern, as only embryos with homogeneous mitochondrial pattern in small aggregates had reduced energy status. CONCLUSIONS This study shows for the first time the joint assessment of chromatin damage and mitochondrial energy/redox potential in fresh and frozen mouse embryos at the morula and blastocyst stage, allowing the comparison of the effects of the two most commonly used cryopreservation procedures.
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Affiliation(s)
- Bence Somoskoi
- Department and Clinic of Obstetrics and Reproduction, Szent Istvan University, Budapest, Hungary.
| | - Nicola A Martino
- Veterinary Clinics and Animal Productions Unit, Department of Emergency and Organ Trasplantation (DETO), University of Bari Aldo Moro Valenzano, Bari, Italy.
| | - Rosa A Cardone
- Department of Bioscience, Biotechnology and Pharmacological Science, University of Bari, 70126, Bari, Italy.
| | - Giovanni M Lacalandra
- Veterinary Clinics and Animal Productions Unit, Department of Emergency and Organ Trasplantation (DETO), University of Bari Aldo Moro Valenzano, Bari, Italy.
| | - Maria E Dell'Aquila
- Department of Bioscience, Biotechnology and Pharmacological Science, University of Bari, 70126, Bari, Italy.
| | - Sandor Cseh
- Department and Clinic of Obstetrics and Reproduction, Szent Istvan University, Budapest, Hungary.
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Martino NA, Dell'aquila ME, Cardone RA, Somoskoi B, Lacalandra GM, Cseh S. Vitrification preserves chromatin integrity, bioenergy potential and oxidative parameters in mouse embryos. Reprod Biol Endocrinol 2013; 11:27. [PMID: 23552480 PMCID: PMC3652727 DOI: 10.1186/1477-7827-11-27] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 03/17/2013] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The aim of this study was to evaluate the effects of vitrification on morpho-functional parameters (blastomere/chromatin integrity and bioenergy/oxidative potential) of mouse preimplantation embryos. METHODS In vivo produced mouse (4/16-cell, morulae and blastocyst-stage) embryos were randomly divided into vitrification and control groups. For vitrification, embryos were exposed to a 2-step loading of ethylene glycol and propylene glycol, before being placed in a small nylon loop and submerged into liquid nitrogen. After warming, the cryoprotectants were diluted by a 3-step procedure. Embryo morphology, chromatin integrity and energy/oxidative status were compared between groups. RESULTS Vitrification induced low grade blastomere cytofragmentation (P < 0.05) and low chromatin damage only in embryos at the morula stage (P < 0.001). Mitochondrial (mt) distribution pattern was affected by vitrification only in early embryos (P < 0.001). Mitochondrial activity did not change upon vitrification in morula-stage embryos but it was reduced in blastocyst-stage embryos (P < 0.05). Intracellular ROS levels significantly increased in embryos at the morula and blastocyst stages (P < 0.001). Colocalization of active mitochondria and ROS increased only in vitrified blastocysts. CONCLUSIONS In conclusion, this study elucidates the developmentally-related and mild effects of vitrification on morphology, nuclear and bioenergy/oxidative parameters of mouse embryos and demonstrates that vitrification is a suitable method for preserving predictive parameters of embryo ability to induce a full-term pregnancy.
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Affiliation(s)
- Nicola A Martino
- Veterinary Clinics and Animal Productions Unit, Department of Emergency and Organ Trasplantation (DETO), University of Bari Aldo Moro, Valenzano, Bari, Italy.
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Jiménez-Trigos E, Naturil-Alfonso C, Vicente JS, Marco-Jiménez F. Effects of cryopreservation on the meiotic spindle, cortical granule distribution and development of rabbit oocytes. Reprod Domest Anim 2011; 47:472-8. [PMID: 22497624 DOI: 10.1111/j.1439-0531.2011.01906.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Although much progress has been made in oocyte cryopreservation since 1971, live offspring have only been obtained in a few species and in rabbits. The aim of our study was to evaluate the effect of vitrification and slow freezing on the meiotic spindle, cortical granule (CG) distribution and their developmental competence. Oocytes were vitrified in 16.84% ethylene glycol, 12.86% formamide, 22.3% dimethyl sulphoxide, 7% PVP and 1% of synthetic ice blockers using Cryotop as device or slow freezing in 1.5 m PROH and 0.2 m sucrose in 0.25 ml sterile French mini straws. Meiotic spindle and CG distribution were assessed using a confocal laser-scanning microscope. To determine oocyte competence, in vitro development of oocytes from each cryopreservation procedure was assessed using parthenogenesis activation. Our data showed that oocytes were significantly affected by both cryopreservation procedures. In particular, meiotic spindle organization was dramatically altered after cryopreservation. Oocytes with peripheral CG distribution have a better chance of survival in cryopreservation after slow-freezing procedures compared to vitrification. In addition, slow freezing of oocytes led to higher cleavage and blastocyst rates compared to vitrification. Our data showed that, in rabbits, structural alterations are more evident in vitrified oocytes than in slow-frozen oocytes, probably as a consequence of sensitivity to high levels of cryoprotectants. Slow-freezing method is currently the recommended option for rabbit oocyte cryopreservation.
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Affiliation(s)
- E Jiménez-Trigos
- Institute of Science and Animal Technology, Laboratorio de Biotecnología de la Reproducción, Universidad Politécnica de Valencia, Valencia, Spain
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