This study was conducted to evaluate whether \"Royal jelly\" (RJ) added to Tris-buffer dilute contributed to supporting post-thaw viability and longevity of frozen canine spermatozoa. Two Japanese spitzs (2 to 4 years of age) were used as a semen donor. Semen was collected by manual masturbation and separated into 3 fractions. Only the sperm-rich fraction having sperm motility of more than 70%, containing sperm concentration of 2~4$\times$10$^{8}$ cells/ml and having dead or abnormal spermatozoa of less than 15% was used for the experiment. Each ejaculated semen was centrifuged at 400 $\times$ g for 5 min and then diluted in a Tris-buffer supplemented with 20 ml egg yolk (Ext I), 4% glycero1 and 1% Equex STM Paste (Ext II) or g1ycero1, Equex STM paste and RJ of various concentrations (Ext II-RJ). After freezing and thawing, viability of spermatozoa in Ext II -RJ containing 1% RJ immediately after thawing (67.5$\pm$9.6) was significantly lower than that of Ext II , Ext II -RJ containing 0.01 or 0.1% RJ (77.5$\pm$12.5, 78.7$\pm$8.2 and 80.0$\pm$6.3). However, Ext II-RJ containing 0.1% RJ yielded higher viability than Ext II, Ext II-RJ containing 0.01% at or 1% 1 h after thawing (69.5$\pm$8.1 vs. 55.0$\pm$12.9, 57.5$\pm$9.6 and 41.5$\pm$12.6; P<0.05). At 1 h after thawing, the viability of spermatozoa thawed in 7$0^{\circ}C$ (68.8$\pm$12.5) was significantly higher than that of spermatozoa thawed in 38$^{\circ}C$ (48.8$\pm$16.3), although there was no difference in the viability between both groups immediately after thawing (77.5$\pm$9.6 and 81.3$\pm$8.1). Post-thaw viability and longevity of post-thaw spermatozoa in Ext II-RJ containing 0.1% RJ was higher in those in Ext II at 1 h (65.0$\pm$12.9 vs. 42.5$\pm$12.6), 2 h (52.5$\pm$12.6 vs. 27.5$\pm$17.1) and 3 h (40.0$\pm$14.1 vs. 20.0$\pm$12.1) after thawing. These results indicated that addition of 0.1% af to Tris-buffer enhanced post-thaw viability and longevity of canine spermatozoa and this additive can be used for increasing the possibility of collision between spermatozoa and ova during insemination.emination.
Proceedings of the Korean Society of Embryo Transfer Conference
/
2002.11a
/
pp.85-85
/
2002
Pregnancy block by male pheromones in mice differs in incidence depending on the combination of strains. Female mice of BALB/cA strain mated with BALB/cA males show a 100% pregnancy block when exposed to males of inbred strain DDK shortly after copulation (Chung et al., Biol Reprod 1997). In the present study, BALB/cA females mated with the males of other strains (CBA/J, C3H/HeN, C57BL/6Cr, and IXBL) showed higher pregnancy rates (66.6-87.5%) even when they were exposed to DDK males. In the pharmacological induction of pregnancy block with dopamine agonist (Bromocriptine, 4mg/kg BW), BALB/cA females mated with BALB/cA males showed a 100% pregnancy block. In contrast, BALB/cA females mated with CBA/J, C3H/HeN, and C57BL/6Cr males showed higher pregnancy rates (40-70%). These results suggest that the better pregnancy rate of BALB/cA females mated with alien males may be due to the stronger viability of F 1 embryos. This interpretation was confirmed by an embryo transfer experiment in which a higher implantation rate was observed when BALB/cA embryos grown in BALB/cA females exposed to BALB/cA males were transferred into recipient BALB/cA females exposed to DDK males. These results suggest that the embryonic genotype or viability of the embryo is one factor contributing to the occurrence of pregnancy block by male pheromones in mice.
Inoculated anthers of Capsicum annuum L. were subjected to 4 and 32$^{\circ}C$ pretreatment and their influence on the microspore viability, early cytological changes and the induction frequency of microspore embryo was investigated. Viability of freshly isolated microspores was between 62 and 64%. During temperature pretreatment, microspore viability showed a rapid decrease and this tendency enhanced with the 32$^{\circ}C$ pretreatment. Irrespective of temperature pretreatment, microspore viability declined to nearly zero after nine days. Before temperature pretreatment, most of the microspores in anthers were at late uninucleate stage. Several types of multinuclear microspores appeared from the 2 day after culture onwards, together with many degenerated and non-induced microspores. The 32$^{\circ}C$ pretreatment gave higher proportions of embryogenic microspore than other treatment. However, the temperature pretreatment had no clear effect on the frequencies of symmetrical binucleate rnicrospore. The multinucleate grains might originate either by symmetrical or asymmetrical division. After 2 days of pretreatment at 25 and 32$^{\circ}C$ , degenerated microspore increased above 50%. In contrast, during 4$^{\circ}C$ treatment, nucleus of most microspores remained intact for 14 days. The 32$^{\circ}C$ pretreatment produced more embryos than 4$^{\circ}C$ treatment. The most effective period of 32$^{\circ}C$ pretreatment was 4 days. In contrast, effective period of 4$^{\circ}C$ pretreatment was 2 days and longer time had deleterious effect on induction of microspore embryo.
Bae, Kee-Hwa;Ko, Myoung Suk;Lee, Mi Hyun;Kim, Nam Young;Song, Jae Mo;Song, Gwanpil
Journal of Plant Biotechnology
/
v.40
no.1
/
pp.43-48
/
2013
Oreorchis coreana Finet is threatened globally by over-collection from its natural habitats for horticultural purposes. Its rarity in nature makes this plant one of the most endangered species in Korea. In this study, we investigated the effects of sodium hypochlorite (NaOCl) on orchid seed viability and seed germination. An in vitro bioassay swelling test using immature seeds was compared with a standard chemical procedure using triphenyl tetrazolium chloride (TTC) to test seed viability. In general, the bioassay was more appropriate for estimating embryo viability after a prolonged pre-treatment (more than 1 h) in 1% NaOCl, a surface sterilant often used to enhance germination of seeds of terrestrial plants. Therefore, an efficient method for investigating in vitro swelling of immature seeds is urgently needed. We established a method for determining the viability and swelling of O. coreana seeds via in vitro examination of immature seeds. Treatment of immature seeds with 1% NaOCl for 10 min greatly enhanced the extent of swelling of immature zygote embryos when compared to untreated seeds. These data obtained here appear to be comparable to viability and swelling that occurs in O. coreana seeds via asymbiotic germination.
This study was carried out to establish most suitable freezing condition, to evaluate the different glycerol concentration of freezing and thawing rates on motility, viability, membrane integrity and acrosome intecrity of frozen Korean Jeju Black Bull spermatozoa, Semen was collected from a Korean Jeju Black Bull using an artificial vagina and transported to the laboratory. The semen was extended gradually 1:5 then cooled slowly for 2 hrs to 4$^{\circ}C$. The semen was diluted 1:1 with cryoprotectant extenders (3%, 5% and 7% glycerol) and equilibrated for 2 hrs at cold chamber and packed to 0.5 ml straws. The semen straws were located above 3 cm of liquid nitrogen for 5 minutes, above 5 cm for 10 min and above 8 cm for 10 min. And then the frozen straw was plunged into LN$_2$. The presented straws were examined the viability and motility after thawed at 37$^{\circ}C$ water bath. The viability and membrane integrity immediately post-thawing were significantly higher in samples frozen in 7% glycerol than 3% and 5% glycerol (p<0.05). After CTC staining to assess acrosome integrity, F pattern was significantly increased, but B pattern was significantly decreased in 7% glycerol (p<0.05). Freezing distance of 5 cm from liquid nitrogen and pre-cooling for 10 min yield better survival and membrane integrity, but not significant difference. However, AR pattern according to CTC staining was significantly decreased in 3 cm for 5 min.
The objective of this study was to evaluated the efficiency on sperm cryosurvival and ability of in vitro fertilization using Triladyl and Lactose Egg-Yolk(LEY) as extenders for cryopreservation of separated sperm by 65% percoll in miniature pig. Sperm viability was measured with SYBR-14/PI double stained sperm by flow cytometry. Ability on embryo cleavage rate and blastocyst development were observed by in vitro fertilization after frozen-thawing of sperm separated by 65% percoll. The experimental groups were designed that separated sperm by 65% percoll with Triladyl (ST) or LEY(SL) and unseparated sperm with Triladyl(UT) or LEY(UL) for cryopreservation. As a results, the viability was significantly(p<0.05) higher in ST(55.1%), SL(63.1%), UL(58.8%) than UT(38.2%) group. Sperm viability in SL(63.1%) group was significantly(p<0.05) higher than other experimental groups. On the other hand, embryo cleavage rate was significantly(p<0.05) higher in ST(79.1%), SL(83.2) than UT(74.1) and UL(75.7%) groups at 96h after in vitro fertilization. Blastocyst development was also significantly(p<0.05) higher in ST(21.5%), SL(20.9%) than UT(17.0%) and UL(18.8%) groups. In conclusion, cryopreservation of miniature boar sperm separated by 65% percoll were beneficial to viability and capacity on in vitro fertilization.
The cryopreservation of sperm has become the subject of research for successful artificial insemination technologies. Antifreeze proteins (AFPs), one of the factors necessary for effective cryopreservation, are derived from certain Antarctic organisms. These proteins decrease the freezing point of water within these organisms to below the temperature of the surrounding seawater to protect the organism from cold shock. Accordingly, a recent study found that AFPs can increase the motility and viability of spermatozoa during cryopreservation. To evaluate this relationship, we performed cryopreservation of boar sperm with AFPs produced in the Arctic yeast Leucosporidium sp. AFP expression system at four concentrations (0, 0.01, 0.1, and $1{\mu}g/ml$) and evaluated motility using computer assisted sperm analysis. DNA damage to boar spermatozoa was measured by the comet assay, and sperm membrane integrity and acrosome integrity were evaluated by flow cytometry. The results showed that motility was positively affected by the addition of AFP at each concentration except $1{\mu}g/ml$ (p<0.001). Although cryopreservation with AFP decreased the viability of the boar sperm using, the tail DNA analyses showed that there was no significant difference between the control and the addition of 0.1 or $0.01{\mu}g/ml$ AFP. In addition, the percentage of live sperm with intact acrosomes showed the least significant difference between the control and $0.1{\mu}g/ml$ AFP (p<0.05), but increased with $1{\mu}g/ml$ AFP (p<0.001). Our results indicate that the addition of AFP during boar sperm cryopreservation can improve viability and acrosome integrity after thawing.
W.S. Moon;S.R. Jeong;S.H. Jung;B.H. Son;Lee, J. W.;I.K. Kong
Proceedings of the Korean Society of Embryo Transfer Conference
/
2002.11a
/
pp.83-83
/
2002
The purpose of this study was to investigate the warming temperature and exposed time on the post-thaw survival rate and viability of bovine blastocyst cryopreserved by GMP vitrification. Groups of three bovine IVP blastocysts were sequentially placed into vitrification solution before being loaded into the GMP straws and immersed into LN$_2$within 20 to 25 sec. The warming rate was increased 2 times of warming temperature for improvement of post-thaw survival rates. The frozen embryos were warmed either at 35 or 70$^{\circ}C$ for 1 or 2 sec and then diluted in sucrose solution. Post-thaw blastocysts were serially washed in 0.25 and 0.15 M sucrose in holding medium (HM: TCM199 supplemented with 10% FCS) and TCM-199 for each 5 min, respectively, and then cultured in TCM199 for 24 h. The rate of re-expanded blastocyst was significantly different fer 35 and 70$^{\circ}C$ warming temporature (76.4 vs. 89.3%; P<0.05). The rate of re-expanded blastocyst at 70$^{\circ}C$ for 1 sec was significantly higher than that for 2 sec (91.1 vs. 70.9%; P<0.05). The number of nuclei counted were significantly different among control, 35 and 70$^{\circ}C$ (121${\pm}$8.5 vs. 104${\pm}$11.7 vs. 114${\pm}$10.3; P<0.05). These results indicated that the increasing of warming rate can provide high survival rates of bovine IVP blastocysts. Especially, the best viability of post-thaw blastocyst could be thaw at 70$^{\circ}C$ for 1 sec. The warming temperature and exposed time far warming was considered to be limiting factors to the viability of bovine IVP embryos. he purpose of this study was to investigate the warming temperature and expose.
Spermatozoa sorted by flow cytometry have been successfully used to produce offspring in domestic animals and are commercially available for cattle. Also sheath fluid is the important environment for viability of sex-sorted sperm in flow cytometry. The aim of this study was to investigate whether or not HEPES (N-2-hydroxyethylpiperazine-N'-2-Ethanesulfonic acid) has any effect on the viability in sex-sorted Hanwoo (Korean native cattle) sperm. In this study, the semen was collected from Hanwoo of Hoengseong Livestock Cooperation by artificial vagina method then pooled and subjected to cryopreservation in straws. Sperm were cultured for 0, 30, 60 and 120 min with 0, 2.5, 5, 7.5 and 10 mM of HEPES added to the sheath fluid and incubated at 4, 20 and 38$^{\circ}C$, respectively. For the cytometric analysis the frozen-thawed semen was extended with 5 mM HEPES extender to final concentration ($2{\times}10^7$ spermatozoa) at 4, 20 and 37$^{\circ}C$. Sperm viability was assessed with SYBR-14 and propidium iodide (PI) staining. This study shows that the viability of sperm was decreased with prolongation of incubation time in all of test. But the viability of sperm which were treated with 38$^{\circ}C$ was gently decreased than that of treated with other temperature. The viability of the control was sharply decreased (p<0.05) than all of the HEPES treatment group at 60 to 120 min in 38$^{\circ}C$. X-sexed sperm was more sensitive than Y-sexed sperm to temperature during f10w cytometry (p<0.05). In conclusion, the results of this study suggest that the sheath fluid with 5 mM HEPES has effect on maintenance of viability after sperm sexing at 37$^{\circ}C$ in Hanwoo.
Spermatogonial stem cells (SSCs) developed into sperms through spermatogenesis have been utilized as a useful tool in the field of regenerative medicine and infertility. However, a small number of highly qualified SSCs are resided in the seminiferous tubule of testis, resulted in developing effective in-vitro culture system of SSCs for solving simultaneously quantitative and qualitative problems. Presently, SSCs can be enriched on testicular stromal cells (TSCs), but there are no systematic researches about TSC culture. Therefore, we tried to optimize culture condition of TSCs derived from mouse with different strains. For these, proliferation and viability were measured and compared by culturing ICR outbred or DBA/2 inbred mouse-derived TSCs at 35 or $37^{\circ}C$. In case of ICR strain, primary TSCs cultured at $37^{\circ}C$ showed significantly higher proliferation and viability than those at $35^{\circ}C$ and significant increase of proliferation and viability in sub-passaged TSCs was detected in the $35^{\circ}C$ culture condition. Moreover, sub-passage of primary TSCs at $35^{\circ}C$ induced no significant effects on proliferation and viability. In contrast, in case of DBA/2 strain, significantly improved proliferation were detected in the primary TSCs cultured at $35^{\circ}C$, which showed no significant difference in the viability, compared to those at $37^{\circ}C$. Furthermore, sub-passaged TSCs cultured at $37^{\circ}C$ showed no significant differences in proliferation and viability, compared to those at $35^{\circ}C$. However, with significant decrease of proliferation induced by sub-passage of primary TSCs at $35^{\circ}C$, no significant effects on proliferation and viability were resulted from sub-passage of primary TSCs at $37^{\circ}C$. From these results, culture temperature of primary TSCs derived from outbred and inbred strain of mouse could be separately optimized in primary culture and subculture.
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