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 926 毫秒
1.
Cultured red porgy Pagrus pagrus (L.) males (n=6) were sampled every 2 weeks for milt, in order to monitor changes in sperm quality parameters during a whole spawning period. On 11 January 2001, 60% of the fish were spermiating, increasing to 100% in mid‐February and dropping to 30% by mid‐April. Sperm density showed a slight increasing trend, with mean values ranging between 8.6 and 23.7×109 spermatozoa mL?1. Sperm motility percentage exhibited a significant improvement during the spawning season (analysis of variance (anova ) P=0.0001). The duration of forward motility for the major part of the monitoring period ranged between 2 and 4 min. Red porgy spermatozoa maintained their viability for many days after whole storage of milt at 4°C. During the monitoring period there were significant changes in the mean duration of sperm survival after cold storage, ranging from 5 to 12 days. The total volume of expressible milt was maximal on 28 March, increasing from a mean value of 1.7 mL to 5.3 mL kg?1. Milt production of captive‐reared red porgy does not appear to be limiting, when compared with the volume of expressible milt produced by other cultured marine fishes.  相似文献   

2.
In this research, the mineral and organic composition of the seminal plasma, physical spermatological parameters and their physiological relationships were investigated in grass carp (Ctenopharyngodon idella). The seminal plasma contained 98.14±5.23 mM L?1 (Na+), 380.85±25.95 mM L?1 (K+), 30.25±4.96 mg dL?1 (Ca2+), 19.16±1.70 mEq L?1 (Mg2+), 1.36±0.11 mg dL?1 glucose, 0.37±0.08 g dL?1 total protein, 12.02±1.18 mg dL?1 cholesterol, 14.85±1.50 mg dL?1 triglyceride and 43.5±9.56 mg dL?1 urea. The following spermatological parameters were found: sperm volume 14.44±1.16 mL, sperm motility 80.60±1.55%, movement duration 67.68±4.32 s, density 15.43±0.72 × 109 mL?1, total density 337.43+45.86 × 109 and pH 7.24±0.17. The Na+ and Ca2+ ions correlated negatively with spermatozoa motility (r=?0.453, P>0.05 and r=?0.192, P>0.05) respectively. The K+ ion correlated positively with spermatozoa motility (r=0.545, P>0.05). But a statistically significant correlation was not observed between sperm motility and seminal plasma parameters. The following correlations were observed between mineral and organic components. The Mg2+ was positively correlated with glucose and cholesterol (r=0.692, P<0.05 and r=0.680, P<0.05) respectively. A highly significant positive relationship was also found between Mg2+ and total protein (r=0.837, P<0.01). On the other hand, a significantly negative relationship was found between Ca2+ and triglyceride (r=?0.639, P<0.05). These parameters should be considered when developing procedures for either artificial fertilization or for cryopreservation of grass carp sperm.  相似文献   

3.
In this study, the effects of spermiation time are investigated on milt quality of Russian sturgeon over the course of the spawning season. The milt samples were collected from three broodstock batches at three time points including: the beginning, middle and at the end of the spawning season. According to the results, the milt quality parameters including pH, sperm density, spermatocrit, duration of sperm motility and percentage of sperm motility were significantly low in the beginning and end of season than middle of season. The values of milt quality parameters in the middle of season were as follows: (motility percentage: 69.6 ± 3.5, motility duration: 460.3 ± 37.2 s, sperm density: 8.7 ± 0.4 × 109, milt volume: 86.3 ± 8.1 and milt pH: 8.3 ± 0.15). Significant positive correlations were also found between milt pH and sperm motility as well as between sperm density and spermatocrit. In conclusion, our study showed that the middle of season is the best time for collection of milt with appropriate quality in Russian sturgeon. Selection of milt with good quality is necessary aim to cryopreservation of spermatozoa in endangered fish species including Russian sturgeon.  相似文献   

4.
This study was carried out to evaluate milt quality in male Caspian brown trout (Salmo trutta caspius) over the course of the winter spawning season. Milt samples were collected biweekly during December and January. Chemical composition of seminal fluid, sperm production (milt volume, sperm density, spermatocrit,) and sperm motility characteristics (percentage and duration of motility) were measured. Milt volume, sperm density, osmolality, seminal minerals (Ca2+, Mg2+, K+, Na+, Cl?), and total protein gradually decreased over the spawning season. Glucose and triglyceride content of milt did not show significant changes over the spawning season. Milt pH and the percentage and duration of motility were comparatively stable, declining only at the end of the season. Significant positive correlations were found between sperm density and seminal minerals, total protein and spermatocrit; percentage of motile spermatozoa and seminal minerals, total protein; and duration of motility and K+, Cl?, total protein, and pH. Results show that season has a significant influence on milt quality in male Caspian brown trout, with the best milt being available at the beginning of spawning season.  相似文献   

5.
Spermiation in 3‐year‐old sterlet, Acipenser ruthenus (L.), males maintained under warm water conditions was induced by intramuscular injection of either (i) (D‐Ala6)‐GnRH‐ProNHEt (Kobarelin); (ii) mammalian GnRH analogue+metoclopramide (Ovopel); or (iii) human chorionic gonadotropin (Biogonadyl). The volume of milt, sperm concentration and motility were measured. A higher percentage of spermiating males was obtained after Kobarelin or Ovopel treatment (81.8% and 77.7% respectively) in comparison with fish treated with Biogonadyl (40.0%). However, only stimulation with Ovopel guaranteed motile spermatozoa in all spermiating males. Moreover, treatment with Ovopel resulted in the highest average milt volume, sperm concentration and motility. The average total number of motile spermatozoa (milt volume×sperm concentration×sperm motility) per individual was 0.99×109, 5.31×109 and 0.02×109 after stimulation with Kobarelin, Ovopel or Biogonadyl respectively. Our data indicate that Ovopel is a good stimulator of spermation in sturgeons. Moreover, the time of sexual maturation could be significantly reduced in sturgeons maintained in cages under warm water conditions.  相似文献   

6.
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   

7.
Sperm density, mineral and organic composition of the seminal plasma and their physiological relationship were investigated in the Caspian brown trout (Salmo trutta caspius). To establish a rapid and accurate method for assessment of sperm density, three different techniques were used: sperm counting, spectrophotometry (at 480 nm) and determination of the spermatocrit. The seminal plasma contained 159.26±8.84 mM sodium (Na), 33.72±2.01 mM potassium (K), 133.04±5.96 mM chlorine (Cl), 1.68±0.2 mM calcium (Ca) and 0.988±0.13 mM magnesium (Mg). The following organic components were found: total protein 0.75±0.14 mg 100 mL−1, cholesterol 2.86±0.58 mg L−1 and glucose 3.81±1.04 mM L−1. The mean sperm density was estimated to be 3.3 × 109 spermatozoa mL−1. The spermatocrit (%) ranged from 25 to 52 in sperm samples. Highly significant linear relationships were found between sperm density and spermatocrit (R2=0.703, P<0.001) and sperm density and optical density (R2=0.909, P<0.001), indicating that optical density can be used as a quick and accurate method of estimating sperm density. Significant relationships were also found between sperm density and Ca, Mg and total protein of seminal plasma. A significant correlation was also observed between the Ca and Mg concentrations (R2=0.774, P<0.01). The following correlations were observed between mineral and organic components: total protein and Ca (R2=0.462, P<0.05), total protein and Mg (R2=0.518, P<0.05) and glucose and Cl (R2=0.374, P<0.05). These parameters should be considered when developing procedures for either artificial fertilization or for cryopreservation of sperm.  相似文献   

8.
This study investigated the composition of milt of the South American silver catfish (Rhamdia quelen) or jundiá. The semen was taken from jundiá in different periods during the four seasons. The biochemical composition of seminal fluid and the characteristics of sperm were analyzed. The semen quantity which can be extracted per fish in one day was 0.95 ± 0.08 ml during spring (maximum) and 0.24 ± 0.03 ml during winter (minimum). Sperm density (spermatocrit) showed higher values in the spring (75.1 ± 1.3%) decreasing slightly afterwards and reaching 63.0 ± 2.4% to 65.0 ± 2.2% in the fall and winter. Immediately after water dilution, 90–100% of the spermatozoa presented vigorous straightforward motility that remained for at least 20 s. The total duration of the motility was 47.9 ± 1.3 s in the spring and 38.6 ± 0.6 s in the other seasons (P < 0.05). This pattern of motility is maintained for more than 2 h after storage of the milt at room temperature. The pH from 5 to 10 of the water dilution does not influence the sperm motility. The mean seminal pH and osmolality values were 8.7 ± 0.07 and 274.8 ± 11.2 (mOsm/kg), respectively. The ion concentration was: Na 153.7 ± 2.4, K 10.7 ± 2.4, Cl 139.4 ± 2.1, Ca 4.2 ± 0.2, Mg 0.9 ± 0.05, P 0.9 ± 0.08 (mEq/l). The total protein was 0.6 ± 0.05 mg/dl and cholesterol concentration was 13.9 ± 0.9 mg/dl.  相似文献   

9.
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   

10.
The effects of extracellular ions on the acquisition and maintenance of the potential for motility in the spermatozoa of the ayu, Plecoglossus altivelis Temminck et Schlegel (Osmeridae), were examined. Testicular spermatozoa and milt spermatozoa were obtained from fully matured males and diluted with buffered solution (BS, 20 mM HEPES–NaOH, pH 7.5). Testicular spermatozoa showed a significantly low rate of motility (0.8 ± 0.4%), whereas milt spermatozoa showed a high rate (89.4 ± 2.1%). The spermatozoa were incubated with various isotonic media for 2 h, diluted with BS, and changes in the rates of motility were then compared. When incubated for 2 h with artificial seminal plasma (ASP), corresponding in terms of ionic constituents to seminal plasma buffered at pH 8.0, both spermatozoa showed a high rate of motility. Testicular spermatozoa acquired and milt spermatozoa maintained the potential for motility in response to the HCO3– ion concentrations (between 0 and 20 mM) in the ASP. The differences in the pH of the ASP had a significant effect on the acquisition and maintenance of the potential for motility, and spermatozoa showed the highest rate of motility with the ASP at pH 8.0 and 8.5. These results suggest that the quality of milt in the ayu can be regulated by controlling the concentration of bicarbonate and the pH of the incubating media.  相似文献   

11.
Spermatozoa concentration, ionic composition, osmolality, glucose and total protein contents of seminal plasma and sperm motility were determined in Barbus sharpeyi (Cyprinidae, Teleosotei). Spermatozoa concentration ranged from 9.77 to 20.20 × 109 spermatozoa mL?1. Osmolality (mOsmol kg?1) and ionic contents (mM L?1) of the seminal plasma were 274.5±9.0, 70.0±3.4 Na+, 28.8±0.9 K+, 101.7±3.1 Cl?, 0.9±0.1 Mg2+ and 2.1±0.1 Ca2+ respectively. Total protein and glucose were 5.3±0.2 g L?1 and 76.7±4.3 mM L?1 respectively. Sperm motility was initiated in a hypo‐osmotic condition, composed of either an ionic (KCl or NaCl) or a non‐ionic (sucrose) activation medium. Duration of sperm motility was very short: <2 min after activation in distilled water. Percentage of motile spermatozoa was significantly higher in an activation medium containing NaCl compared with that of distilled water. An activating medium containing NaCl or KCl higher than 150 mM or sucrose higher than 275 mM totally inhibited the activation of sperm motility. Immediately after sperm activation, wave(s) propagated along the flagellum, but waves were restricted to the proximal part of the flagellum (close to the head) at 1 min post activation. Studied characteristics in the present study were compared with those of other cyprinids for understanding inter‐species differences.  相似文献   

12.
The effectiveness of applying Ovaprim [(D-Arg6, Pro9NEt)-sGnRH + domperidone] and Ovopel [(D-Ala6, Pro9NEt)-mGnRH + metoclopramide] to male barbel Barbus barbus (L.) 6, 12 and 24 h after hormonal stimulation was analyzed. The control group (Control) during each time interval was stimulated with 0.9 % NaCl. Milt was collected from seven fish only once (n = 7) for Ovopel, Ovaprim and Control group in order to determine total volume of milt, volume of milt per kg of body weight, sperm concentration, total sperm production, seminal plasma osmotic pressure, pH of milt and pH of seminal plasma. Woynarovich’s solution (68 mM NaCl + 50 mM urea) with the addition of 0.5 % BSA (pH 7.7; 181 mOsm kg?1) was used as the activating liquid. Selected parameters of sperm motility (MOT %) and progressively motile sperm (%), curvilinear velocity (VCL, μm s?1), straight-line velocity (μm s?1), movement linearity (%), wobbling index (%), amplitude of lateral head displacement (μm) and beat cross frequency (Hz) were determined using the Computer-assisted sperm analysis system. A time of 6 h proved to be too short to obtain milt from barbel following hormonal stimulation with Ovaprim and Ovopel. Extending the time to 12 h, however, resulted in 100 % spermiation in males, regardless of hormonal preparation used for stimulation. The stimulation of spermiation in barbel is best performed using Ovopel 12 h upon application. Extending the latency period to 24 h following the application of this preparation results in a significant decrease in the volume of milt obtained, sperm count and motility parameters, including MOT and VCL, which may influence sperm fertilization ability.  相似文献   

13.
The present study investigated the effects of sequential collection of milt, time of post-mortem storage and anesthesia on rainbow trout (Oncorhynchus mykiss) sperm motility parameters (using computer-assisted sperm analysis – CASA) as well as seminal plasma osmolality and sperm concentration. The post-mortem storage and time of anesthesia altered motility characteristics of rainbow trout sperm to different extents. The moderate impact of time of anesthesia was manifested in a shortened duration of sperm motility after 10 min exposure of fish to anesthetic. The prolonged post-mortem storage (≥40–60 min), in addition to lowering sperm motility duration, also significantly influenced sperm motility parameters, such as sperm velocities, percentage of motile sperm and sperm trajectory parameters. These results clearly demonstrate that when milt from sacrificed fish is used for sperm motility studies, the time of post-mortem storage significantly alters sperm motility characteristics. Since sperm motility rate and swimming velocity could predict fertilizing ability, detrimental effects of prolonged post-mortem storage may lead to reduced fertilization success. Sperm concentration and seminal plasma osmolality were lower in the first fractions and increased with successive collections of milt. It suggests the presence of urine contamination of the first milt fractions which were collected by stripping. Therefore, testing of sperm concentration and/or seminal plasma osmolality should be mandatory while handling stored milt.  相似文献   

14.
The commercial‐scale production of fish by use of artificial (induced) spawning would require reliable, large‐volume sources of sperm. Cryopreservation can be used to preserve and store sperm within commercial and research germplasm repositories, but is limited in its application to aquaculture. Straw volume and cooling chamber size restrict the quantity of sperm that can be frozen, and straws must be filled by hand. In contrast, the dairy industry has refined methods for freezing of bull sperm, including automation of straw filling and the use of large cooling chambers. These methods could be used for commercial‐scale cryopreservation of fish sperm, although application would require testing. To supply sperm in large volumes, bags originally developed for swine semen could be cooled using dairy protocols and used as a container for fish sperm. The current study documented the use of commercial‐scale dairy cryopreservation techniques for the production of hybrids of channel catfish Ictalurus punctatus (female) by blue catfish Ictalurus furcarus. Four cryoprotectants (methanol, dimethyl sulfoxide, dimethyl acetamide, and glycerol) were initially evaluated for use with blue catfish sperm. During May 2000 and March to April 2001, suspensions of blue catfish sperm were cryopreserved with 10% methanol in 0.5‐mL French straws and in commercial swine semen bags (Cochette* bags, IMV International. Minneapolis, Minnesota, USA). Cryopreservation took place at a dairy breeding cooperative, using technology employed for bull semen. Sperm motility before freezing was 26 ± 18% during Year 1 (2000) and 62 ± 30% during 2001. Sperm were thawed at 40 C and used to fertilize the eggs of channel catfish (yielding hybrids). Motility after thawing for sperm frozen in 0.5‐mL straws was 11 ± 10% during 2000 and 50 ± 24% during 2001. Motility after thawing was 41 ± 17% for sperm frozen in swine semen bags in 5‐mL aliquots and 43 ± 10% for sperm frozen in 10‐mL aliquots. Neurulation of eggs fertilized with thawed sperm from straws was 83 ± 13% during 2000 and 54 ± 27% during 2001. Neurulation was 57 ± 24% using sperm frozen in swine semen bags in 5‐mL aliquots and 55 ± 10% using sperm frozen in 10‐mL aliquots. There was no correlation between sperm motility before freezing (in 0.5‐mL straws) and after thawing during 2000 (r= 0.52) or during 2001 (r= 0.49). In addition, there was no correlation between initial motility and neurulation of channel catfish eggs fertilized using thawed sperm during 2000 (r= 0.14) or during 2001 (r= 0.29). Sperm of blue catfish can thus be cryopreserved at a commercial scale using dairy protocols and can be made available for the production of hybrid catfish when viable eggs are available.  相似文献   

15.
This study reports on the spermatological properties, and on the development of a protocol for refrigerator storage (4°C) of Labeo calbasu (Hamilton, 1822) sperm for artificial breeding. Volume, motility, concentration and pH of the freshly collected sperm were 2.21 ± 0.53 (μL g?1 of fish weight) (mean ± SD), 95 ± 1 (%), 1.93 ± 0.44 × 109 (cells mL?1) and 7.56 ± 0.17 respectively. Sperm activation was evaluated at different osmolalities of NaCl solution, and motility ceased completely when osmolality of the extender was ≥287 mOsmol kg?1. Sperm retained motility for 24, 72 and 108 h, after refrigerator storage when sperm were undiluted, suspended in Alsever's solution and suspended in Alsever's solution containing 5% methanol respectively. Fertilization rate of fresh eggs with sperm stored at 4°C in Alsever's solution and Alsever's solution containing 5% methanol was 77% and 60% with a hatching rate of 60% and 43% respectively. The fertilization and hatching success of the stored sperm suggests potential to use refrigeration for transporting genetic material to hatcheries for artificial breeding of L. calbasu in Bangladesh.  相似文献   

16.
Milt quality of Waigieu seaperch was sampled at the beginning, the middle, and the end of the spawning season to assess if the sampling season has an effect on milt quality parameters. The milt volume and total sperm production were higher at the middle of the spawning season while the sperm concentration in milt was significantly higher at the beginning and the end of the spawning season. Sperm morphology and the major parameters of seminal plasma (pH, total protein, Mg2+, or Ca2+ concentrations) did not differ throughout the spawning season. The concentrations of Na+ and the osmolality increased throughout the spawning season. The percentage of motile cells did not differ during the spawning season while the duration of sperm motility (swimming duration) and velocity (swimming speed) were significantly different during the spawning season. The fertilization rate (75.7 ± 6.8%) and hatching rate (56.5 ± 3.1%) at the middle of the spawning season were higher than at the beginning and end periods. Results indicated that milt quality parameters and fertility success in the middle of the spawning season were higher compared to earlier and later sampling dates. Thus, we recommend collecting milt during this time for maximal fertilization and hatching success.  相似文献   

17.
The aim of this study was to evaluate the sperm quality of Brazilian flounder Paralichthys orbignyanus throughout its reproductive season. Sperm was collected at the beginning, middle and end of the breeding period. Spermatozoa density was maximum at the beginning (12.7 ± 0.92 × 109 cells mL?1) and at the end (11.8 ± 0.39 × 109 cells mL?1) of the breeding season (P<0.05). Sperm production and the percentage of spermatozoa moving fast forward increased significantly towards the end of the breeding season (P<0.05). The mean duration of progressive motility of spermatozoa was around 10 min. No difference was observed during the reproductive season in the percentage of motile cells, pH, osmolality and K+, Cl? and Mg2+ concentrations in seminal plasma. The concentration of Na+ increased throughout the breeding season, reaching 174.62 ± 12.68 mmol L?1 at the end (P<0.05). There was a decline in the concentration of Ca2+ (12.31 ± 3.08 mmol L?1) in the middle of the breeding season, which coincided with the shortest motility duration of spermatozoa. The information reported in this study should help to improve management and optimize the development of protocols for short‐term storage and cryopreservation of Brazilian flounder semen.  相似文献   

18.
Collection of fish milt by stripping risks the danger of milt contamination by urine. This may seriously influence milt characteristics and quality, including usefulness for cryopreservation. Urine contamination of milt may be avoided by using a catheter for sperm collection. The objectives of this study were to provide basic characteristics of milt collected with a catheter, to test the usefulness of this milt for cryopreservation, and to correlate characteristics of fresh and cryopreserved semen with sperm fertility rates. Milt from 25 rainbow trout Oncorhynchus mykiss (Walbaum) males were used. All samples were cryopreserved using the pellet method within 1 h of collection, using 0.6 m sucrose and 10% dimethyl sulphoxide (DMSO) as an extender. Catheterization resulted in semen of very good motility (> 90% motile spermatozoa) and high fertilization rates after cryopreservation (mean fertilization rate 81.8 ± 13.3% of control, at a sperm/egg ratio of 2.4 ± 0.3 × 106). Osmolality of seminal plasma and concentrations of sodium, potassium and magnesium ions had low variability, which suggests that they are important for creating a stable environment for sperm storage in the sperm duct. Higher variability of certain seminal plasma characteristics, such as protein concentration and antiproteinase activity, suggests that these characteristics are related to individual semen features of particular males. A strong correlation of seminal plasma zinc concentration with protein concentration may reflect an importance of zinc in semen biology. Cryopreservation caused a significant release of protein and acid phosphatase from spermatozoa. Our results did not reveal any single characteristic of semen collected by catheter that could be used as a powerful predictor of cryopreservation success, presumably because all samples were of high quality.  相似文献   

19.
To provide necessary standardization of procedures for cryopreservation of sperm, a spectrophotomeric method was developed to determine the sperm concentration of diploid and tetraploid Pacific oysters, Crassostrea gigas. Wavelengths of 380, 550, 581 and 780 nm were compared, and 550 and 581 nm were found to be the most sensitive and reliable. A linear relationship between sperm concentration and photometric absorbance was observed for sperm concentrations between 2 × 107 and 2 × 109 cells mL?1. The regression equation for the standard curve at 550 nm for sperm of diploid oysters was Y=?8.528+1.165 log X. The equation for sperm of tetraploid oysters was Y=?8.844+1.236 log X. The equation at 581 nm for sperm of diploid oysters was Y=?8.07+1.104 log X. The equation at 581 nm for sperm of tetraploid oysters was Y=?8.331+1.167 log X. Comparisons derived from the standard curves at 581 nm between observed values and the predicted values indicated good agreement for sperm from diploid (coefficient of determination, r2=0.983) and tetraploid (r2=0.980) oysters.  相似文献   

20.
In the present study, attempts were made to preserve Urechis unicinctus sperm at 4°C. Cryopreservation procedures were optimized for various cryoprotectants and freezing rates, equilibration times and dilution ratios. During short‐term storage, the motility of undiluted sperm was extended for 6 days of cold storage,and in 70% and 100% artificial seawater only persisted for 2 and 4 days respectively. The survival rate of undiluted sperm was maintained at a high level accordingly. After cryopreservation, the highest motility and survival rate (41.5±2.2%) were obtained in 15% dimethyl sulphoxide (Me2SO) using a freezing rate of 30°C min?1. After thawing the sperm cryopreserved in glycerol lost almost all motility. The motility and survival rate of post‐thawing sperm did not show significant differences after 8 and 15 min equilibration using 15% Me2SO as cryoprotectant; the values were significantly higher than those of 2 min equilibration. Comparisons of motility and survival rate between treatments pooled by dilution ratio showed that the effect of 1:1 ratio (sperm volume to cryoprotectant volume) was best. There was no difference between 1:3 and 1:5, and other ratioswere significantly worse.  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