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Di Iorio M, Lauriola F, Rusco G, Antenucci E, Schiavitto M, Iaffaldano N. Cryopreserving Rabbit Semen: Impact of Varying Sperm Concentrations on Quality and the Standardization of Protocol. Vet Sci 2023; 11:9. [PMID: 38250915 PMCID: PMC10818829 DOI: 10.3390/vetsci11010009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 12/06/2023] [Accepted: 12/20/2023] [Indexed: 01/23/2024] Open
Abstract
This study aimed to investigate the impact of sperm concentrations on the in vitro quality of cryopreserved rabbit semen. The semen pools (n = 8, from 80 donors) were split into five aliquots with final sperm concentrations of 15, 25, 35, 55, and 75 × 106 per straw. The sperm motility parameters (CASA system) and membrane integrity (flow cytometric analysis) were both evaluated at various stages of the cryopreservation process: fresh semen dilution, cooling, equilibration, and immediately after and 30 min post-thawing. The results indicated the significant influence of the sperm concentration on the total motility (TM) and progressive motility (PM), with a consistent decline in all sperm variables over the time points. Notably, the semen with a final concentration of 15 × 106 exhibited a higher TM and PM after cooling and equilibration. The post-thawing quality (TM, PM) was higher (p < 0.05) in the mid-range sperm concentrations of 25 × 106 (49.9% and 19.7%) and 35 × 106 (46.2% and 19.7%) compared to the other concentrations. This study demonstrated that the sperm concentration per straw played a significant role in specific phases of the cryopreservation process. These findings contribute valuable insights for refining and standardizing the cryopreservation protocol for rabbit semen, emphasizing the importance of the sperm concentration.
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Affiliation(s)
- Michele Di Iorio
- Department of Agricultural, Environmental and Food Sciences, University of Molise, Via De Sanctis snc, 86100 Campobasso, Italy; (M.D.I.); (F.L.); (G.R.); (E.A.)
| | - Fabrizio Lauriola
- Department of Agricultural, Environmental and Food Sciences, University of Molise, Via De Sanctis snc, 86100 Campobasso, Italy; (M.D.I.); (F.L.); (G.R.); (E.A.)
| | - Giusy Rusco
- Department of Agricultural, Environmental and Food Sciences, University of Molise, Via De Sanctis snc, 86100 Campobasso, Italy; (M.D.I.); (F.L.); (G.R.); (E.A.)
| | - Emanuele Antenucci
- Department of Agricultural, Environmental and Food Sciences, University of Molise, Via De Sanctis snc, 86100 Campobasso, Italy; (M.D.I.); (F.L.); (G.R.); (E.A.)
| | - Michele Schiavitto
- Italian Rabbit Breeders Association (ANCI-AIA), Volturara Appula, 71030 Foggia, Italy;
| | - Nicolaia Iaffaldano
- Department of Agricultural, Environmental and Food Sciences, University of Molise, Via De Sanctis snc, 86100 Campobasso, Italy; (M.D.I.); (F.L.); (G.R.); (E.A.)
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Mohammed KM, Darwish GM, Rawash ZM, Taha AM. Cryopreservation of rabbit semen: impacts of permeable and non-permeable mixture of cryoprotectant, male group individuality, freezing rate, semen package size and antioxidant bovine serum albumin on rabbit semen freezability. WORLD RABBIT SCIENCE 2022. [DOI: 10.4995/wrs.2022.17303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
In the present study, three experiments were designed to identify the most appropriate technique for freezing rabbit semen. Experiment 1 aimed to determine the optimal levels of dimethyl sulfoxide (DMSO) contents in freezing medium and their effects on individual bucks. Semen ejaculates for each buck (n=15 bucks) were mixed and split into three portions for extension with a freezing medium containing varying concentrations of DMSO (0.75, 1.0, and 1.4 M). Diluted semen samples were packaged in 0.25 mL straws and suspended above liquid nitrogen (LN) for 10 min, then dipped in LN. A few days after freezing, post-thaw semen evaluation was assessed, and according to the results, six bucks and an extender containing 0.75 M of DMSO were used for experiments 2 and 3. In experiment 2, the pooled semen from 6 bucks was divided into two portions for packaging in two straw sizes (0.25 and 0.50 mL). Each straw size was divided into five groups and suspended at different heights above LN (2, 4, 6, 8, and 10 cm) for 10 minutes before being preserved in LN. In experiment 3, the pooled semen was divided into four portions for dilution with freezing medium containing different concentrations of bovine serum albumin (BSA; 0, 2.5, 5.0, and 7.5 mg/mL). Semen samples were packaged in a 0.50 mL straw and suspended 10 min, 4 cm above LN for freezing. Pre-freezing and post-thawing, semen samples were evaluated for semen quality. Results showed that the extender containing 0.75 M DMSO had higher significant values for post-thaw sperm motility, longevity, acrosome integrity and sperm plasma membrane permeability. Bucks’ individuality had significant effects on post-thaw motility, acrosome and sperm plasma membrane integrity. A significant interaction was recorded between DMSO concentrations and bucks’ individuality on sperm longevity. Semen package sizes had no significant effects on the evaluated parameters. Semen was frozen at 2 and 4 cm above LN had significantly better post-thaw quality. BSA at concentrations 5 and 7.5 mg/mL improved recovery rates of acrosome integrity and sperm membrane permeability. DMSO 0.75 M and freezing 4 cm above LN seem to be more adequate for rabbit semen cryopreservation. The appropriate level of DMSO differs between bucks, as the post-thaw sperm longevity is affected. BSA enhanced acrosome and sperm membrane integrity. Results obtained will need further investigation to be confirmed in the field.
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Küçük N, Uçan U, Raza S, Erdoğan G, Aksoy M. Comparative efficiency of novel laparoscopic and routine vaginal inseminations with cryopreserved semen in rabbits. Reprod Domest Anim 2021; 56:1059-1065. [PMID: 33966306 DOI: 10.1111/rda.13949] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 05/05/2021] [Indexed: 12/14/2022]
Abstract
Laparoscopic artificial insemination technique (LAI) is described to overcome reduced fertility problems in sheep artificial insemination (AI) programmes with frozen semen. Later on, this technology was modified for endangered non-domestic cats to deposit low quality or reduced number of sperm cells hardly obtained by electro-ejaculation into the oviduct. This technique by passes the complex structure of cervix and efficiently transfers the sperm cells to the point of fertilization. In recent years, rabbits are becoming popular transgenic animal models producing various therapeutic and commercial products, as well as being experimental animals for disease models. The worldwide transportation of frozen semen and re-establishment of transgenic lines using AI technology has become a common practice. Therefore, this study was designed to describe a laparoscopic intrauterine insemination technique, which might assist in conceiving the animals with limited number of sperm cells. The female rabbits were laparoscopically (n = 22) or vaginally (n = 13) inseminated with frozen-thawed semen samples containing approximately 10 × 106 motile sperm. The laparoscopic insemination technique provided higher pregnancy rate (45.5%) than vaginal insemination technique (7.7%) (p < .05). In conclusion, the described laparoscopic AI might be a new alternative technique, thus enabling limited or low-quality frozen sperm samples to establish pregnancy in rabbits.
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Affiliation(s)
- Niyazi Küçük
- Faculty of Veterinary Medicine, Department of Reproduction and Artificial Insemination, University of Aydın Adnan Menderes, Aydın, Turkey
| | - Uğur Uçan
- Faculty of Veterinary Medicine, Department of Reproduction and Artificial Insemination, University of Aydın Adnan Menderes, Aydın, Turkey
| | - Sanan Raza
- Faculty of Veterinary Medicine, Department of Reproduction and Artificial Insemination, University of Aydın Adnan Menderes, Aydın, Turkey.,Department of Animal Reproduction, University of Veterinary & Animal Sciences, Lahore, Pakistan
| | - Güneş Erdoğan
- Faculty of Veterinary Medicine, Department of Veterinary Obstetrics and Gynecology, University of Aydın Adnan Menderes, Aydın, Turkey
| | - Melih Aksoy
- Faculty of Veterinary Medicine, Department of Reproduction and Artificial Insemination, University of Aydın Adnan Menderes, Aydın, Turkey
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Nishijima K, Kitajima S, Matsuhisa F, Niimi M, Wang CC, Fan J. Strategies for Highly Efficient Rabbit Sperm Cryopreservation. Animals (Basel) 2021; 11:ani11051220. [PMID: 33922622 PMCID: PMC8145333 DOI: 10.3390/ani11051220] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/20/2021] [Accepted: 04/21/2021] [Indexed: 12/28/2022] Open
Abstract
The rabbit is a valuable animal for both the economy and biomedical sciences. Sperm cryopreservation is one of the most efficient ways to preserve rabbit strains because it is easy to collect ejaculate repeatedly from a single male and inseminate artificially into multiple females. During the cooling, freezing and thawing process of sperms, the plasma membrane, cytoplasm and genome structures could be damaged by osmotic stress, cold shock, intracellular ice crystal formation, and excessive production of reactive oxygen species. In this review, we will discuss the progress made during the past years regarding efforts to minimize the cell damage in rabbit sperms, including freezing extender, cryoprotectants, supplements, and procedures.
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Affiliation(s)
- Kazutoshi Nishijima
- Center for Animal Resources and Collaborative Study, National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
- National Institute for Physiological Sciences, National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki 444-8585, Japan
- Department of Physiological Sciences, SOKENDAI (The Graduate University for Advanced Studies), Aichi, Okazaki 444-8585, Japan
- Correspondence: (K.N.); (J.F.); Tel.: +81-564-557781 (K.N.); +81-55-2739519 (J.F.)
| | - Shuji Kitajima
- Analytical Research Center for Experimental Sciences, Division of Biological Resources and Development, Saga University, 5-1-1 Nabeshima, Saga 849-8501, Japan; (S.K.); (F.M.)
| | - Fumikazu Matsuhisa
- Analytical Research Center for Experimental Sciences, Division of Biological Resources and Development, Saga University, 5-1-1 Nabeshima, Saga 849-8501, Japan; (S.K.); (F.M.)
| | - Manabu Niimi
- Department of Molecular Pathology, Faculty of Medicine, Interdisciplinary Graduate School of Medical Sciences, University of Yamanashi, 1110 Shimokato, Chuo 409-3898, Japan;
| | - Chen-chi Wang
- Animal Resources Section, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa 904-0495, Japan;
| | - Jianglin Fan
- Department of Molecular Pathology, Faculty of Medicine, Interdisciplinary Graduate School of Medical Sciences, University of Yamanashi, 1110 Shimokato, Chuo 409-3898, Japan;
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, China
- Correspondence: (K.N.); (J.F.); Tel.: +81-564-557781 (K.N.); +81-55-2739519 (J.F.)
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Jimoh OA. Potential of coconut water to enhance fresh semen quality and fertility in rabbits. Trop Anim Health Prod 2019; 52:249-255. [PMID: 31302834 DOI: 10.1007/s11250-019-02011-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 07/08/2019] [Indexed: 11/25/2022]
Abstract
Coconut water as a natural diluent was evaluated on rabbit semen quality, conception and litter size in artificially inseminated does. A total of 10 bucks and 90 does, all crossbred New Zealand White × chinchilla, were used for the trial. Pooled semen was obtained from bucks using artificial vagina. Semen diluents were prepared at 0%, 20%, 40%, 60% and 80% and control 50% normal saline and designated as T1, T2, T3, T4, T5 and T6 respectively, in a completely randomised design. Semen analysis was conducted on fresh semen and the various diluted semen immediately at 37 °C. Fifteen does each were randomly allotted to the different treatment and were inseminated with their respective treatment diluted semen using the standard procedure, and conception rate, litter size and productivity index at birth were assessed at kindling. Result obtained revealed that spermatozoa motility and structural membrane integrity of the diluted semen were significantly (p < 0.05) affected by the percentage of dilution. The range of values obtained for spermatozoa motility, structural membrane integrity and acrosome integrity is within the accepted values for good-quality semen. Conception rate, litter size and productivity index at birth were highest in does inseminate with T4 (60%), and the least values were obtained in T5 (80%). In conclusion, coconut water is a suitable diluent for rabbit semen for on-farm artificial insemination, the optimal dilution rate of coconut water in rabbit semen is 60%, which guarantees high conception, litter size and productivity index at birth.
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Affiliation(s)
- O A Jimoh
- Animal Physiology Laboratory, Department of Animal Science, University of Ibadan, Ibadan, Nigeria. .,Agricultural Technology Department, Federal Polytechnic Ado Ekiti, Ado Ekiti, Ekiti State, Nigeria.
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Abstract
In this study, fresh and frozen-thawed semen of Nitra and Zobor rabbit breeds were evaluated for potential inter-breed or inter-male differences in sperm quality traits. Individual male semen from four rabbits of each breed were diluted (v:v; 1:1) in a freezing medium composed of a commercial diluent, 16% of dimethyl sulphoxide (DMSO), 4% of Ficoll 70 and 2% of sucrose and frozen in liquid nitrogen vapours before being plunged into liquid nitrogen. Different motility traits, viability and plasma membrane integrity of fresh and frozen-thawed semen were evaluated in vitro using computer-assisted sperm analysis and flow cytometry. To evaluate the sperm fertilization ability, artificial insemination of fresh and frozen-thawed sperm was performed. Our results showed the effect of breed (P ≤ 0.05) on frozen-thawed sperm viability and plasma membrane integrity. Moreover, individual variability in semen quality among the rabbits was revealed (0.31 to 0.71 among quality traits). Our results thereby confirmed that the cryopreservation procedure could not ensure comparable sperm post-thaw survival for different breeds or males. Nevertheless, correlations between numbers of fresh total motile and progressively moving sperm and several quality parameters measured post thawing were revealed. Therefore, we suggest that the objective assessment of fresh rabbit sperm motility may be an effective indicator of frozen-thawed semen quality. Consequently, regular semen assessment is required in order to preserve good-quality insemination doses from native breeds.
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Mocé E, Blanch E, Talaván A, Viudes de Castro MP. Effect of different freezing velocities on the quality and fertilising ability of cryopreserved rabbit spermatozoa. Reprod Fertil Dev 2017; 27:846-51. [PMID: 25483855 DOI: 10.1071/rd14009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 02/09/2014] [Indexed: 11/23/2022] Open
Abstract
The freezing step of the cryopreservation protocol negatively influences the quality and fertilising ability of rabbit spermatozoa. This study determines the effect of different rates of freezing on the quality and fertilising ability of rabbit spermatozoa cryopreserved with dimethylsulfoxide (DMSO) (1.75M) and sucrose (0.05M). Ejaculates from meat rabbit line males (n=12) were pooled and each pool (n=7) was split into four aliquots. One group of straws (control, C) was frozen in static liquid nitrogen vapour (5cm above the liquid nitrogen, 10min) and the other groups were frozen at different freezing rates (°Cmin(-1)) from -6°C to -100°C using a programmable freezer: slow (-15°Cmin(-1), S), medium (-40°Cmin(-1), M) or fast (-60°Cmin(-1), F). After thawing (50°C, 12s), the quality was highest (P<0.05) in C and M samples and lowest in S and F samples. F samples presented the lowest litter sizes (P≤0.05) and fertility whilst M samples exhibited the highest values. In conclusion, the freezing rate affects both the quality and the fertilising ability of frozen-thawed rabbit spermatozoa, with both slow (-15°Cmin(-1)) and fast (-60°Cmin(-1)) freezing rates being detrimental for the quality and fertilising ability.
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Affiliation(s)
- E Mocé
- Centro de Tecnología Animal - Instituto Valenciano de Investigaciones Agrarias (CITA-IVIA), Polígono La Esperanza, 100. Apdo. 187. 12400 - Segorbe (Castellón), Spain
| | - E Blanch
- Centro de Tecnología Animal - Instituto Valenciano de Investigaciones Agrarias (CITA-IVIA), Polígono La Esperanza, 100. Apdo. 187. 12400 - Segorbe (Castellón), Spain
| | - A Talaván
- Centro de Tecnología Animal - Instituto Valenciano de Investigaciones Agrarias (CITA-IVIA), Polígono La Esperanza, 100. Apdo. 187. 12400 - Segorbe (Castellón), Spain
| | - M P Viudes de Castro
- Centro de Tecnología Animal - Instituto Valenciano de Investigaciones Agrarias (CITA-IVIA), Polígono La Esperanza, 100. Apdo. 187. 12400 - Segorbe (Castellón), Spain
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8
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Effect of freezing extender composition and male line on semen traits and reproductive performance in rabbits. Animal 2014; 8:765-70. [DOI: 10.1017/s1751731114000135] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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In vitro survival and lipid peroxidation status of rabbit spermatozoa after both chilled and frozen storage in lycopene enriched extenders. Livest Sci 2012. [DOI: 10.1016/j.livsci.2012.03.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Mocé E, Lavara R, Vicente JS. Effect of cooling rate to 5 °C, straw size and farm on fertilizing ability of cryopreserved rabbit sperm. Reprod Domest Anim 2011; 45:e1-7. [PMID: 19650879 DOI: 10.1111/j.1439-0531.2009.01507.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
High fertility and prolificacy in rabbits are currently only achieved using fresh sperm. This study was conducted to determine if the cooling rate to 5 °C, the straw size and the farm where artificial inseminations are performed have an impact on the fertilizing ability of rabbit sperm cryopreserved with an extender containing dimethyl sulphoxide (DMSO; 1.75 m) and sucrose (0.05 m). Slow cooling to 5 °C improved neither fertility rate (58 vs 56% kindling rate for fast and slow cooling, respectively) nor prolificacy (6.5 vs 8.7 total born for slow and fast cooling, respectively; p < 0.05) compared to fast cooling rate to 5 °C. The straw size did not have an effect on either fertility or prolificacy (47 vs 57% kindling rate and 6.3 vs 6.8 total born for sperm loaded into 0.25 and 0.5 ml straws, respectively). In addition, similar results were obtained between farms (46-57% kindling rate and 4.9-6.7 total born), although this effect should be studied further. In conclusion, with this extender, slow cooling does not present a beneficial effect on sperm fertilizing ability and either 0.25 or 0.5 ml straws can be used to freeze the sperm, obtaining similar results after artificial insemination. In addition, similar results were obtained between farms when using cryopreserved sperm, and these results were lower than those obtained after artificial insemination with fresh semen. Therefore, new approaches are needed to improve the results obtained when cryopreserved sperms are used before this type of sperm can be used for commercial purposes.
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Affiliation(s)
- E Mocé
- Instituto Valenciano de Investigaciones Agrarias, Centro de Tecnología Animal, Polígono La Esperanza, Segorbe, Spain.
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Abstract
INTRODUCTIONArtificial insemination (AI) is used in rabbit husbandry to improve breeding management. Conception rates after AI with fresh semen are equivalent to or even better than those obtained by natural mating. Also, AI has the advantage of avoiding contact between animals. Furthermore, AI with frozen sperm is particularly useful for assisted reproduction and conservation of rabbit genetic resources, and in some cases, frozen semen produce results similar to those obtained in AI using fresh sperm. This protocol describes the most commonly used protocol for AI using fresh sperm.
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Affiliation(s)
- Nathalie Daniel
- Unité Mixte de Recherche UMR 1198, Biologie du Développement et Reproduction, Institut National de la Recherche Agronomique, F-78350 Jouy-en-Josas, France.
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12
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Abstract
Menopause is the final step in the process referred to as ovarian ageing. The age related decrease in follicle numbers dictates the onset of cycle irregularity and the final cessation of menses. The parallel decay in oocyte quality contributes to the gradual decline in fertility and the final occurrence of natural sterility. Endocrine changes mainly relate to the decline in the negative feedback from ovarian factors at the hypothalamo-pituitary unit. The declining cohort of antral follicles with age first results in gradually elevated FSH levels, followed by subsequent stages of overt cycle irregularity. The gradual decline in the size of the antral follicle cohort is best represented by decreasing levels of anti-Mullerian hormone. The variability of ovarian ageing among women is evident from the large variation in age at menopause. The identification of women who have severely decreased ovarian reserve for their age is clinically relevant. Ovarian reserve tests have appeared to be fairly accurate in predicting response to ovarian stimulation in the assisted reproductive technology (ART) setting. The capacity to predict the chances for spontaneous pregnancy or pregnancy after ART appears very limited. As menopause and the preceding decline in oocyte quality seem to have a fixed time interval, tests that predict the age at menopause may be useful to assess individual reproductive lifespan. Especially genetic studies, both addressing candidate gene and genome wide association, have identified several interesting loci of small genetic variation that may determine fetal follicle pool development and subsequent wastage of his pool over time. Improved knowledge of the ovarian ageing mechanisms may ultimately provide tools for prediction of menopause and manipulation of the early steps of folliculogenesis for the purpose of contraception and fertility lifespan extension.
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Affiliation(s)
- F J Broekmans
- Department of Reproductive Medicine and Gynecology, University Medical Center, Utrecht, The Netherlands.
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Mocé E, Vicente JS. Rabbit sperm cryopreservation: A review. Anim Reprod Sci 2009; 110:1-24. [DOI: 10.1016/j.anireprosci.2008.08.015] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2008] [Revised: 08/11/2008] [Accepted: 08/11/2008] [Indexed: 12/20/2022]
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Broekmans FJ, Knauff EAH, te Velde ER, Macklon NS, Fauser BC. Female reproductive ageing: current knowledge and future trends. Trends Endocrinol Metab 2007; 18:58-65. [PMID: 17275321 DOI: 10.1016/j.tem.2007.01.004] [Citation(s) in RCA: 275] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2006] [Revised: 12/22/2006] [Accepted: 01/24/2007] [Indexed: 10/23/2022]
Abstract
Over the past few decades, postponement of childbearing has led to a decrease in family size and increased rates of age-related female subfertility. Age-related decrease in ovarian follicle numbers and a decay in oocyte quality dictate the occurrence of natural loss of fecundity and, ultimately, menopause. The rate of this ovarian ageing process is highly variable among women. Identification of women who have severely decreased ovarian reserve for their age is, therefore, clinically relevant. Endocrine and imaging tests for ovarian reserve relate mainly to the quantitative aspect of ovarian reserve, but their capacity to predict the chances for pregnancy is limited. Genetic factors regulating the size of the follicle pool and the rate of its depletion might be identified in the near future and, possibly, assist the accurate prediction of a woman's reproductive lifespan.
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Affiliation(s)
- Frank J Broekmans
- Department of Reproductive Medicine and Gynecology, University Medical Center Utrecht, Utrecht, The Netherlands.
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Kashiwazaki N, Okuda Y, Seita Y, Hisamatsu S, Sonoki S, Shino M, Masaoka T, Inomata T. Comparison of Glycerol, Lactamide, Acetamide and Dimethylsulfoxide as Cryoprotectants of Japanese White Rabbit Spermatozoa. J Reprod Dev 2006; 52:511-6. [PMID: 16679717 DOI: 10.1262/jrd.18008] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The rabbit is considered to be a valuable laboratory animal. We compared glycerol, lactamide, acetamide, and dimethylsulfoxide (DMSO) as cryoprotectants in egg-yolk diluent of ejaculated Japanese white rabbit spermatozoa for improvement of sperm cryopreservation methods. Rabbit semen was frozen with 1.0 M glycerol, lactamide, acetamide, or DMSO in plastic straws. Forward progressive motility and plasma membrane integrity of the post-thaw spermatozoa were examined. The rate of forward progressive motile spermatozoa in lactamide (37.8 +/- 3.0%) was significantly (P<0.05) higher than in glycerol (17.0 +/- 3.3%). In addition, the rates of sperm plasma membrane integrity in lactamide and acetamide (35.9 +/- 3.3% and 30.2 +/- 3.0%, respectively) were significantly (P<0.05) higher than in glycerol (17.0 +/- 2.6%). The results indicate that 1.0 M lactamide and acetamide have higher cryoprotective effects than 1.0 M glycerol for cryopreservation of Japanese white rabbit spermatozoa.
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Affiliation(s)
- Naomi Kashiwazaki
- Laboratory of Animal Reproduction, School of Veterinary Medicine, Azabu University, Japan.
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