首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 140 毫秒
1.
The effects of extender composition and freezing rate on motility and fertility of frozen‐thawed Arctic char, Salvelinus alpinus, spermatozoa were investigated. Three freezing rates, two semen diluents and three cryoprotectants were tested. Semen frozen in 0.3 mol L?1 glucose diluent with 10% methanol as a cryoprotectant or in a diluent described by Lahnsteiner with 10%N,N‐dimethylacetamide (DMA) resulted in the highest sperm motility. Fertility was the highest for semen frozen in a glucose–methanol extender but was not significantly different than that for semen frozen in Lahnsteiner's diluent with 10% DMA. Dimethyl sulphoxide (DMSO) at 10% was a relatively ineffective cryoprotectant with either semen diluent. Semen frozen at 6 cm above the surface of liquid nitrogen resulted in a higher post‐thaw sperm motility and fertility than semen frozen at 5 cm. The addition of 7% fresh egg yolk to glucose diluent containing methanol or DMSO did not improve the fertility of frozen‐thawed spermatozoa. However, the addition of 7% fresh egg yolk to glucose–DMA extender significantly improved the fertilization percentages of frozen‐thawed spermatozoa. In conclusion, dilution of semen 1:3 in 0.3 mol L?1 glucose with 10% methanol and freezing 6 cm above the surface of liquid nitrogen (freezing rate of 40±8°C min?1, mean±SD from ?5 to ?55°C) is a promising protocol for cryopreservation of Arctic char semen.  相似文献   

2.
Crappie, Pomoxis spp., are popular game fish throughout North America and are produced by public and private hatcheries. However, production is limited by a lack of information on tank culture and induced spawning methods. Development of techniques for storage of sperm and in vitro fertilization would increase flexibility in spawning. Therefore, techniques for sperm cryopreservation were examined in white crappie, Pomoxis annularis. Sperm from adult wild white crappie were used to evaluate sperm extender, cryoprotectant agent and concentration, and cooling technique based on post‐thaw sperm motility. Percent egg fertilization was also compared between sperm stored in the two best cryopreservation protocols and two different osmotic activator solutions. Sperm were cryopreserved using treatment combinations of two extenders (350 mOsmol/kg Hanks' balanced salt solution [HBSS] and 350 mOsmol/kg Ca2+free HBSS) and two cryoprotectants (dimethyl sulfoxide [DMSO] and methanol) at concentrations of 5, 10, and 15% that were cooled at four different rates: 5, 10, 20, and 40 C/min. Post‐thaw sperm motility and fertilization rates indicated white crappie sperm can be cryopreserved using either extender, cryoprotectants of either 5% DMSO or 10% methanol, and cooling at 40 C/min. A follow‐up experiment demonstrated sperm in suspensions on ice retained viability after overnight transport.  相似文献   

3.
Three experiments were performed to develop protocols for cryopreservation of Persian sturgeon Acipenser persicus, sperm. In the first experiment, sperm from six males was individually split in three subsamples and cryopreserved using Modified Tsvetkova's extender (mT) supplemented with dimethyl sulfoxide (DMSO), methanol (MeOH), glycerol (Gly) and ethylene glycol (EG) at concentration of 5%, 10%, 15% and 20%. In the second set of experiments, the effects of six equilibration times (0, 5, 10, 20, 40 and 60 min) and dilution ratios (volume sperm: volume extender 1:0.5, 1:1, 1:2, 1:3, 1:5 and 1:10) and the additive advantage of bovine serum albumin (BSA; 0, 2.5, 5 and 10 mg mL?1) and ascorbic acid (0, 2.5, 5 and 10 U mL?1), on the post‐thaw survival of sperm (triplicate set of six fish) were evaluated. Then, sperm was diluted in 1:1 mT extender with 10 mg mL?1 BSA with selected cryoprotectants (15% MeOH and 10% DMSO) for 5 min. After a month of storage in liquid nitrogen, post‐thawed sperm motility; fertilization and hatching rate and viability of derived larvae were measured (Exp.3). Evaluation of cryoprotectants efficiency showed that MeOH 15% and DMSO 10% were suitable for cryopreservation of Persian sturgeon sperm. Gly and EG resulted in very low post‐thaw motility rates even at lowest concentration. No significant difference was observed among the four different equilibration times (0, 5, 10, 20 min) (P > 0.05) although higher equilibration times than 20 min resulted low post‐thaw motility (P < 0.05). The motility of frozen–thawed sperm did not significantly change when dilution ratio was increased from 1:0.5 to 1:3 (P > 0.05). However, higher dilution ratios (1:5 and 1:10) reduced the percentage of motile sperm. Supplementation of the cryoprotectant solution with 10 mg mL?1 BSA significantly improved post‐thaw motility (P < 0.05), but ascorbic acid did not improve post‐thaw motility (P > 0.05). The results of experiment 3 showed that the highest fertilization (30.2 ± 5.75) and hatching rates (28.2 ± 5.25) were observed when samples were frozen with 15% MeOH (P > 0.05). Our study indicates that the use of mT extender consisting of 10 mg mL?1 BSA in 15% MeOH diluted with sperm at 1:1 ratio for 5 min can be recommended cryopreservation method for Persian sturgeon sperm.  相似文献   

4.
The Southern flounder, Paralichthys lethostigma, is a valuable aquaculture fish with established markets in the USA. All‐female production in this species is an important technology for aquaculture because the females usually have body sizes twice those of males at the same age, and sex‐reversed males (genotypic XX neomales) are used for all‐female production by crossing with genetically normal females. However, sperm volume from the neomales is usually small (<0.5 mL) and limits their application for all‐female fish production. Cryopreservation of sperm from these sex‐reversed neomales will provide access on demand with increased efficiency to extend the application of neomales. The goal of this study was to develop a protocol for cryopreservation of sperm from the Southern flounder by using an automated high‐throughput processing system. The objectives were to: (1) determine the effect of osmolality on activation of sperm motility; (2) evaluate the effect of extender solutions on sperm motility capacity; (3) evaluate the acute toxicity of cryoprotectants (dimethyl sulfoxide [DMSO], propylene glycol, and polyethylene glycol) on sperm motility, and (4) estimate the effect of cooling rate on sperm cryopreservation and post‐thaw fertilization. Sperm motility was activated when osmolality was 400 mOsmol/kg or higher. Of the three extender buffers tested, HEPES4‐(2‐hydroxyethyl)‐1‐piperazineethanesulfonic acid (HEPES) at 300 mOsmol/kg resulted in better protection for sperm motility than did Hanks' balanced salt solution and Mounib solution at 300 mOsmol/kg during 7 d of refrigerated storage. After 30 min equilibration with the cryoprotectant of 15% DMSO, sperm motility was 24 ± 21% (fresh sperm motility without any cryoprotectants was 42%). After cooling at a rate of 20 C/min, post‐thaw sperm motility was 8 ± 5% and fertilization was 63 ± 40% evaluated at the 32–64 cell stage (5 × 105 sperm per egg). Overall, a protocol was developed for sperm cryopreservation in the Southern flounder with high‐throughput processing, which provides a tool to preserve the valuable genetic resources from neomale flounders, and enables germplasm repository development for the Southern flounder.  相似文献   

5.
Experiments were carried out to develop an optimal cryopreservation protocol for tench sperm by testing the fertilizing capacity and motility parameters including progressive motility, curvilinear velocity (VCL) and linearity (LIN) of cryopreserved sperm. Three experiments were designed to this aim: first experiment where we tested the effects of two extenders (sugar‐based Grayling and ion‐based Kurokura 180) and two cryoprotectants (DMSO and methanol) on fertilization and hatching success; second where we tested the effect of cryoprotectant type (methanol or DMSO) in different concentrations (5%, 10% and 15%) on fertilization and hatching success; and third where we tested the effect of two cryoprotectants (methanol and DMSO) on sperm motility parameters (progressive motility, VCL and LIN) after 4 h post‐thaw storage (4°C). Sperm prepared with the sugar‐based Grayling extender displayed better fertilization and hatching rates independently of the applied cryoprotectant most likely due to glucose present which acted as an external cryoprotectant. Concerning cryoprotectant concentrations, the use of 10% methanol yielded the highest fertilization (85 ± 15%) and hatching (80 ± 13%) rates, which were significantly higher than in all other groups. During the post‐thaw storage time, 5% methanol, 10% methanol and 5% DMSO groups had significantly higher motility parameters than other groups and we observed no significant decline in any of the parameters during the storage time. Overall, we found that a sugar‐based extender in combination with methanol as cryoprotectant is suitable for the cryopreservation of tench sperm and allows storage of cryopreserved sperm for up to 4 h post thaw.  相似文献   

6.
In two trials, Arctic char (Salvelinus alpinus) semen was frozen in 0.5 mL straws using extenders consisting of 0.3 M glucose and 10%, 12.5% or 15% methanol. Cryopreserved semen was thawed by immersing straws in 25 °C water for 17 s (11.6 °C s?1) or in 5 °C water for 60 s (3.3 °C s?1). The viability of the frozen–thawed semen was measured by determining post‐thaw motility and sperm membrane integrity. Two fertility trials were also conducted. There was no effect of trial or thaw rate on post‐thaw sperm viability or fertility. Use of 15% methanol in the extender resulted in the highest overall percentage of sperm motility and fertility. Use of 12.5% methanol as a cryoprotectant resulted in a higher per cent post‐thaw motility and a lower percentage of dead cells than did 10% methanol. Thus, levels of methanol higher than the commonly used 10% are beneficial for cryopreserving Arctic char sperm.  相似文献   

7.
Sperm were collected in Florida from wild common snook, Centropomus undecimalis (Bloch), and were shipped to Louisiana State University for analysis and cryopreservation. Threshold activation of sperm (10% motility) occurred at 370 mOsmol kg?1, and complete activation occurred at 680 mOsmol kg?1. These values were significantly different. Sperm samples stored at 1°C in Hanks' balanced salt solution (HBSS) or in 0.6% NaCl solution at 200 mOsmol kg?1 retained motility for as long as 22 days. Mean motility remained above 50% for 9 days for sperm stored in HBSS and for 7 days for sperm stored in NaCl solution. Sperm exposed to 5% dimethyl acetamide (62±10%; mean±SD), 10% dimethyl sulphoxide (DMSO) (39±16%), 5% glycerol (26±5%) or 10% glycerol (6±2%) for 30 min had significantly lower motility than did unexposed sperm (89±9%). When used as a cryoprotectant, samples frozen with 5% or 10% DMSO or 5% methanol had significantly higher post‐thaw motility than did samples frozen with other cryoprotectants. Sperm cryopreserved with 10% DMSO (38±12%) had significantly higher post‐thaw motility than did sperm cryopreserved with 15% DMSO (19±10%) or 20% DMSO (4±4%). There were no significant differences in hatch rates of eggs fertilized with fresh sperm (54±29%) or cryopreserved sperm (41±35%). Survival to first feeding was not different between fish produced with fresh sperm (37±30%; range, 0–86%) or with thawed sperm (24±29%; 0–77%). Transport of sperm to a cryopreservation laboratory and back to a hatchery for thawing and use enabled collaboration between groups with specific expertise and provides a model for the application of cryopreservation by transport of fresh and frozen samples.  相似文献   

8.
The summer flounder, Paralichthys dentatus L., is a high‐value species and considerable research has been conducted to determine practices conducive for its culture. As milt can be limited in this species, experiments were conducted to develop a practical sperm cryopreservation protocol for hatchery use. Two dilution ratios (1:2 and 1:4; sperm:extender), 2 diluents (saline and sucrose‐based), 2 cryoprotectants (10% DMSO and 12% glycerol) and 3 freezing rates (?5, ?10 and ?15°C min?1) were evaluated using differential staining to assess post‐thaw sperm survival. Seven combinations of the factors examined reduced post‐thaw viability by less than 30%. The average viability of sperm from fresh, pooled flounder milt (67.2 ± 2.9%) was not different from that of thawed milt diluted 1:4 with sucrose diluent (10% DMSO) frozen at ?5°C min?1 (38.4 ± 7.7%) and fertilization and hatch success were not different in trials using fresh or thawed, cryopreserved sperm. From these experiments a practical sperm cryopreservation method was developed, but further refinement of the freezing protocol is necessary to optimize results.  相似文献   

9.
Three cryoprotectants (dimethyl sulphoxide, propylene glycol and glycerol) and two diluents (sucrose based and saline based) were mixed (9 parts diluent–1 part cryoprotectant) factorially to produce six extenders that were tested to develop an effective sperm cryopreservation protocol for winter flounder Pseudopleuronectes americanus (Walbaum). Sperm were diluted 1:3 with each extender and frozen by flotation on liquid nitrogen before being submerged and stored for 30 days. Sperm left unfrozen in each extender for 20 min showed no toxic effects on motility. Extenders containing propylene glycol (PG) as cryoprotectant yielded higher post‐thaw sperm motilities than those containing dimethyl sulphoxide (DMSO) or glycerol. The sucrose‐based diluent performed better than the saline‐based diluent when DMSO was used as cryoprotectant, but there were no differences in post‐thaw motility between diluents for the other cryoprotectants. Activating sperm with ovarian fluid and sea water instead of sea water alone had no effect on post‐thaw motility. In fertilization trials, no differences were observed between any of the extenders and fresh milt when milt, eggs and sea water were left in contact for 1 h. When sperm were forced to compete for eggs by reducing contact time to 20 s, fertilization results followed those of sperm motility rates. Percentage hatch and morphology of larvae at hatching did not differ for eggs fertilized by cryopreserved and fresh sperm. This study represents the first reported successful attempt at cryopreserving winter flounder sperm and should improve gamete and broodstock management protocols for this species.  相似文献   

10.
Effectiveness and efficiency of frozen sperm on fertilization and hatching success of eggs from silver barb was examined in relation to cryoprotectants, freezing rate and storage period. Sperm was diluted in calcium‐free Hank's balanced salt solution, equilibrated with dimethylsulphoxide (DMSO), propylene glycol, sucrose or methanol at 5%, 10%, 15% or 20% final concentrations, and frozen in 250‐μL straws using a one‐step freezing procedure (1, 5 and 8°C min?1 from 25 to ?40°C). Highest post‐thaw sperm motility was found from a treatment using 10% DMSO and 5°C min?1 (82.2 ± 2.1%), similar to that of 10% DMSO and 8°C min?1 (87.8 ± 3.2%). Post‐thaw motility of sperm frozen at 5 or 8°C min?1 was significantly higher than 1°C min?1. Relative sperm motility declined significantly after 10 months of cryostorage while viability did not change during a 12‐month cryostorage. Average fertilization rates of sperm after 1 and 4 months of storage were 64.5 ± 4.6% and 61.3 ± 3.4%, respectively, similar to those of fresh sperm (69.6–72.3%). Hatching rates of cryopreserved sperm (45.4–51.2%) were similar to those of fresh sperm (51.8–57.8%). This study developed suitable methods for cryopreservation of silver barb sperm that can be used to facilitate hatchery operation.  相似文献   

11.
This study developed a technique of sperm cryopreservation using liquid nitrogen (LN) vapour in farmed blacklip abalone Haliotis rubra through evaluating the following five key factors: (1) cryoprotectant agent (CPA) toxicity; (2) cooling temperature; (3) thawing temperature; (4) sperm to egg ratio and (5) sugar addition, using sperm motility or fertilization rate as quality assessment indicators. The results demonstrated that 6% dimethyl sulfoxide (DMSO) was the best single CPA for sperm cryopreservation in this species. The highest post‐thaw sperm motility was achieved when sperm were exposed to LN vapour for 10 min at 5.2 cm above the LN surface and thawed at 60°C and recovered at 16°C in seawater baths. Post‐thaw sperm motility was found to be significantly higher when 6% DMSO was used in combination with 1% or 2% glucose than 6% DMSO alone. Further evaluation of fertilization rate between these CPAs showed that 6% DMSO+2% glucose achieved the highest fertilization rate of 70% at a sperm to egg ratio of 10 000:1.  相似文献   

12.
Cryopreservation of Arctic charr Salvelinus alpinus (L.) semen was investigated using three diluents, three cryoprotectants [10% dimethyl sulphoxide (DMSO), 10% dimethylacetamide (DMA) or 20% glycerol] and three sizes of straw. The three diluents and three cryoprotectants were combined, resulting in nine extenders. One part semen was added to three parts extender, and motility was evaluated to assess the toxicity of six of the extenders. Semen in nine extenders was frozen in 0.5‐mL straws using liquid nitrogen vapour. Semen extended in 0.3 m glucose and each of the cryoprotectants was also frozen in 0.5‐mL, 1.7‐mL (flat) or 2.5‐mL straws. The freezing rate in each size of straw was measured. Fertility trials were conducted to determine the post‐thaw viability of the frozen semen. The motility of activated spermatozoa was higher in the DMA and DMSO extenders than in the glycerol extender. For the trial using 0.5‐mL straws, post‐thaw fertility results were higher for all extenders containing DMSO, or 0.3 m glucose and DMA, than for all other combinations of diluent and cryoprotectant. For the straw size comparison, the highest fertility was obtained for the 1.7‐mL straw using either DMSO or DMA and for the 2.5‐mL straw using DMSO. For all cryopreservation trials, fertility was low for extenders containing glycerol.  相似文献   

13.
Cryopreservation of sea cucumber Apostichopus japonicus (Selenka) sperm   总被引：1，自引：0，他引：1  
A simple and convenient method for the cryopreservation of sea cucumber Apostichopus japonicus (Selenka) sperm was tested in the present study. The highest motility (76.7±2.9%) of post‐thawing sperm was obtained in 15% dimethyl sulphoxide (DMSO) with a 1:9 dilution (semen volume to DMSO volume) when 0.5 mL semen–DMSO mixture was frozen at 6 cm above liquid N2 in a closed styrofoam box. After thawing, sperm cryopreserved in glycerol almost lost motility entirely. Although there was no significant difference in percentage of motile sperm between 15% and 20% DMSO, the duration of sperm motility of 15% DMSO group was longer than that of 20% DMSO group. The motility of post‐thawing sperm enhanced when the dilution ratio of semen increased from 1:1 to 1:9. Morphological changes such as the loss of mitochondria, swollen plasma membrane and broken or rolled‐up tails were observed in post‐thawing sperm using an eosin–nigrosin staining. The fertility of cryopreserved sperm was significantly lower than that of unfrozen sperm. The 10‐fold increase in sperm to egg ratio resulted in double fertility for cryopreserved sperm, and about 70% fertility relative to the control.  相似文献   

14.
This study investigated factors key to the development of sperm cryopreservation in the greenlip abalone Haliotis laevigata using a programmable freezing technique, including (1) permeable cryoprotectant agent (CPA) selection; (2) cooling rate; (3) endpoint temperature; (4) thawing temperature; (5) sperm to egg ratio and (6) sugar, vitamin and amino acid supplementation, using sperm motility, fertilization rate, plasma membrane integrity, mitochondrial membrane potential or acrosome integrity as quality assessment indicators. Results showed that among the permeable CPAs evaluated, 10% dimethyl sulfoxide was the most suitable for greenlip abalone sperm cryopreservation. The highest post‐thaw sperm motility was achieved with the sperm being frozen at a cooling rate of ?5°C min?1 to ?30°C from 0°C and thawed and recovered in 40°C and 18°C seawater baths respectively. The addition of sugars in 10% dimethyl sulfoxide did not significantly improve the post‐thaw sperm motility and fertilization rate. The addition of 0.6% glycine, 0.2% taurine or 0.02% L‐ascorbic acid, on the other hand, significantly improved the post‐thaw sperm motility. However, only the addition of 0.6% glycine improved the post‐thaw sperm fertilization rate, which was further confirmed by the improvement of the post‐thaw sperm mitochondrial membrane potential and acrosome integrity through flow cytometry analysis.  相似文献   

15.
The present study investigated motility, acrosome reaction, fertility and cryobiological parameters of the semen of the sterlet, Acipenser ruthenus L. Sperm motility persisted for about 4 min in water, and the main swimming type was the linear motion. Motility was prolonged at osmolalities of 12.5 mosmol kg?1 and in the presence of magnesium ions, while calcium had no effect. Also a pH in the range of 7.0–9.0 had no effect on ` motility. At osmolalities of 25–50 mosmol kg?1 the sperm motility was partly inhibited, at osmolalities of 100 mosmol kg?1, completely and irreversibly. In 50 mosmol kg?1 solutions with 2.5–5 mM L?1 KCl the motility inhibition was total, but reversible. The acrosome reaction was not induced by one of the described solutions, but the percentage of spermatozoa with reacted acrosomes was low (<20%) and highly variable in all experiments. The optimal extender base for cryopreservation was a solution consisting of 50 mM L?1 NaCl, 5 mM L?1 KCl, 10 mM L?1 Tris (pH 8.5). From the tested cryoprotectants only dimethylsulphoxide (DMSO) and methanol provided sufficient cryoprotection. After freezing and thawing, the motility rates and swimming velocities were higher with DMSO than with methanol. However, the fertility was very significantly reduced with DMSO (10.3±0.5%) while with methanol fertilization rates in a similar range (32.7±4.4%) as with fresh semen (33.90±0.8%) could be obtained. Optimal freezing conditions for sterlet semen were in the vapour of liquid nitrogen 3–5 cm (?95°C to ?85°C) above its surface, the optimal thawing conditions at 25°C for 30 s. The acrosome reaction was not induced by these cryopreservation protocols.  相似文献   

16.
Black sea bass Centropristis striata L. are protogynous hermaphrodites that develop and spawn as females before changing sex to male. Since all fish eventually become males, determining the relationship between sperm production, sperm quality and seasonal changes in plasma levels of testosterone (T) and 11‐ketotestosterone (11‐KT) could be useful for identifying appropriate males to maintain as broodstock. Milt and blood samples were collected three times during an 8‐week spawning season. Milt volume (3.5±0.76 mL kg?1), sperm density (3.2 × 108± 0.31 cells mL?1), sperm production [11 × 108±3.4 cells kg?1 body weight (BW)] and sperm motility (80±0.6%) were at their highest during the first sampling interval and coincided with the highest 11‐KT levels (1.0± 0.11 ng mL?1). All of the sperm indices decreased to their lowest levels during the final 3 weeks of the study. Sperm viability was highly correlated (adjusted R2=0.84) with sperm motility. Sperm cryopreserved in modified Mounib's extender (MME) had the highest post‐thaw motility compared with two other extenders. Post‐thaw motility of sperm cryopreserved in MME was not different from fresh after 90 days of storage. There was no difference in fertilization rates between fresh (69±2.4%) and post‐thaw (67±4.1%) sperm samples taken from the same male or among males. These results demonstrate that the quality of black sea bass spermatozoa is higher earlier in the spawning season and that acceptable post‐thaw fertilization rates can be obtained from cryopreserved sperm.  相似文献   

17.
Yellow catfish (Pelteobagrus fulvidraco) is a candidate freshwater fish for aquaculture in China with its high consumer demand. The aim of this study was to examine the possibility of storage of the sperm of yellow catfish by cryopreservation in liquid nitrogen. Experiments were designed to investigate the effects of the different combinations of three extenders (Ringer extender, Kurokura-1 extender and D-15 extender) and three cryoprotectants (DMSO, Glycerol and Methanol) on the cryopreservation of yellow catfish sperm. Post-thaw sperm motility, fertilization and hatching rate were detected to evaluate the reliability of sperm cryopreservation. The results demonstrated that Ringer extender and 10% methanol was the best combination for protecting the sperm during freezing in liquid nitrogen by a three-step method and thawing in a water bath at 37 °C for 60 s. In this combination for cryopreservation, sperm maintained the highest post-thaw motility (65 ± 5%), fertilization (90.47 ± 3.67%) and hatching rate (88 ± 4%). And more interestingly, the fertilization and hatching rate were similar to those of fresh sperm (97.55 ± 2.74% and 92 ± 5%). Successful sperm cryopreservation techniques for yellow catfish have been developed for hatchery purpose.  相似文献   

18.
To develop an appropriate cryopreservation protocol for spermatophores of black tiger shrimp, Penaeus monodon, three cryoprotectants (dimethyl sulphoxide (DMSO), methanol (MeOH) and ethylene glycol (EG)) at two concentrations (5% and 10%) were examined. Artificial implantation of spermatophores was also carried out to assess the fertilizing ability of fresh and post‐thaw spermatophores. Spermatophores were collected during consecutive regenerations (15‐day intervals) and assessed for qualitative and quantitative changes and also for fertilizing ability by implantation. The mean fertilization rate for artificial insemination using post‐thaw spermatophore was 79.9±3.7%, lower than the fertilization rates observed for artificial implantation using fresh spermatophore and natural mating. Mean hatch rates for fresh spermatophore, frozen‐thawed spermatophore and natural mating were 88.8±0.6%, 87.8±0.4% and 88.3±0.5%, respectively; and there was no difference among the three groups. The mean fertilization rate of spermatophores collected during the first stripping was higher (90.6±0.6) than during the second stripping (85.7±2.6), but the mean hatch rate was not different between the two strippings. The highest mean sperm viability (79.7±0.4%) was obtained from DMSO (5%), with no survival observed in the 10% MeOH treatment. Spermatophore weight, total sperm count and percentage of abnormal sperm were not different between spermatophores collected at the first and second stripping. This is the first study to report high fertilization and hatch rates from cryopreserved spermatophore using artificial implantation of spermatophore before spawning.  相似文献   

19.
This study examined the usage of a dry shipper for cryopreservation of Epinephelus septemfasciatus (Thunberg) spermatozoa. Milt was diluted 1:49 with 5% dimethyl sulfoxide plus 95% foetal bovine serum for cryopreservation. Computer‐assisted sperm analysis was used to analyse sperm motility, while fertilization and hatching trials were conducted to gauge the applicability of the cryopreservation method for aquaculture. We showed that cooling rates of the dry shipper were stable for 14 days and could be manipulated by the use of different sized freezing straws and use of a simple polystyrene foam container (5 × 5 × 12 cm and 1 cm thickness on all sides with the upper layer exposed). Dry shipper cryopreserved spermatozoa had significantly lower post‐thaw per cent motility and velocity than fresh sperm, but linearity of movement was unchanged. Fertilization and hatching rates were not significantly different at all tested sperm to egg ratios (3000:1–243000:1). The results indicated that 0.33 mL of milt when cryopreserved was sufficient to fertilize up to 450 g of oocytes. Application of this technology will help improve seed production in aquaculture and further develop breeding and genetics studies.  相似文献   

20.
The effects of extender composition, cryoprotectant concentration and freezing and thawing on the fertilization efficiency of cryopreserved spermatozoa of Puntius gonionotus were evaluated. Computer‐aided motility analysis of semen was conducted to check the suitability of spermatozoa for cryopreservation after mixing with different extenders and cryoprotective agents (CPAs). Extender‐4 with an osmolality 260 mOsmol kg−1and pH 7.6 was used for the cryopreservation study. Among the CPAs, dimethyl sulphoxide (DMSO) was least toxic and more than 60% fertilization was achieved when used at 1.4 M at 0 °C for 10 and 30 min, whereas the toxicity of all CPAs to spermatozoa was evident when tested at 30 °C. Semen frozen at −16 °C min−1 with 1.4 M DMSO showed 70% fertilization, which was significantly higher (P<0.05) than other freezing rates. Samples thawed at 35 °C water showed a fertilization rate comparable with that of fresh semen. Computer‐assisted semen analysis of fresh and frozen semen after thawing showed variations in different types of motility in spermatozoa and in their class. There was no significant difference in motility before or after cryopreservation; however, significant differences could be observed in the average path velocity (VAP), straight line velocity (VSL) and curve linear velocity (VCL). Semen of silver barb could be cryopreserved with extender‐4 by addition of 1.4 M DMSO to a final cryopreservation medium (MED 2) cooled at a rate of −16 °C min−1, stored in liquid nitrogen (−196 °C) and utilized after thawing at 35±2 °C.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号