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 15 毫秒
1.
Two experiments were conducted to test whether stallionand/or semen processing techniques influenced spermatozoal motility and acrosomal status following cold storage. Ejaculates from each of 18 stallions (N=54) were collected and split. In Experiment I, a skim milk-glucose extender (SKMG) was added to the semen following a 5, 15 or 30 minute delay post-collection. Following each delay, sperm were packaged at a final concentration of 25 million progressively motile sperm per ml (PMS/ml) in a commercially available skim milk-glucose extender (SKMG). In Experiment II, sperm were packaged at concentrations of 25, 50, and 75 million PMS/ml both in the presence and absence of seminal plasma (SP) utilizing SKMG and SKMG plus PBS, respectively. In both experiments, aliquots were cooled, stored, and the percentage of progressively motile and acrosome intact spermatozoa were determined at 24 and 48 hours post-collection. In Experiment 1, delayed dilution resulted in a lower recovery of PMS. In Experiment II, removal of SP resulted in higher percentages of PMS following cold storage. Increasing the concentration of spermatozoa during packaging decreased the percentage of PMS; however, removal of SP reduced the harmful effects on spermatozoa motility. These data suggest that reducing the time that spermatozoa remain in an undiluted state and removal of SP maximize recovery of progressively motile, acrosome-intact spermatozoa. In addition, individualizing the processing techniques for each stallion may enhance spermatozoal survival following cold storage.  相似文献   

2.
This study investigated the effects of skim milk on the quality and fertility of boar spermatozoa under long‐term chilled preservation. Semen samples were stored in Modena solution supplemented with 0 (control) to 50 mg/mL skim milk at 5°C for 4 weeks; spermatozoa stored with 7.5 and 15 mg/mL of skim milk (7.5‐SM and 15‐SM groups, respectively) exhibited significantly higher motility indices than those of the control group up to 3 weeks (P < 0.05), and the 7.5‐SM group showed improved motility indices even after 4 weeks (P < 0.05). In vitro fertilization using spermatozoa in the 7.5‐SM and 15‐SM groups stored at 5°C for 2 weeks showed significantly higher fertilization rates of spermatozoa and the development rates to blastocyst than the control group (P < 0.05), and the 7.5‐SM group showed similar rates of fertilization and blastocyst formation in the fresh non‐stored spermatozoa group. After artificial insemination using spermatozoa stored for 2 weeks in the 7.5‐SM group, healthy piglets were obtained. Boar spermatozoa can be stored at 5°C in a Modena solution containing skim milk. Supplementation of 7.5 mg/mL skim milk improves boar spermatozoa motility and fertility even after liquid preservation at 5°C for 2 weeks.  相似文献   

3.
Incubation of dog spermatozoa in a medium without glucose and in the presence of lactate and pyruvate (l-CCM) for 4 h at 38.5 degrees C in a 5% CO(2) atmosphere induced in vitro capacitation of these cells. This was verified after the combined specific capacitation-like changes in percentages of viability and altered acrosomes, motility characteristics, sperm location of reactivity against Pisum sativum, Arachis hypogaea and Helix pomatia lectins and the tyrosine phosphorylation pattern. Furthermore, a feasible acrosome reaction (AR) was induced when spermatozoa incubated in l-CCM for 4 h were further co-incubated for 1 h with canine oocytes. This was demonstrated by AR-like changes in percentages of viability, altered acrosomes, motility characteristics and sperm location of reactivity against P. sativum, A. hypogaea and H. pomatia lectins. All these results clearly indicate that in vitro capacitation, and subsequent AR, can be feasibly achieved without the presence of sugars. This ability can be related to the specific characteristics of energy-metabolism regulation reported in dog spermatozoa.  相似文献   

4.
This study aimed at comparing in vitro, ultra‐heat‐treated (UHT) skim milk and INRA‐96®‐based extenders supplemented or not with 5% egg yolk and/or 2% glycerol on sperm quality parameters along 72 h of preservation at 5°C, using a factorial design. Semen from six healthy mature Merino rams was pooled and extended in each medium using a split sample procedure (six replicates) and chilled. Subjective motility (SM) (%), membrane integrity (MI) (%) and uncapacitated spermatozoa (US) (×106 spermatozoa/AI dose) were used to assess the semen quality at 0, 12, 24, 48 and 72 h of preservation. UHT‐based extenders yielded better (p < 0.05) SM and MI than INRA‐96®‐based extenders (59.7% vs 57.9%; 60.2% vs 55.8%, respectively) but similar numbers of US (64.2% vs 62.3 × 106 sperm/AI dose, respectively) along the preservation time. Egg yolk–glycerol or just egg yolk as additives improved (p < 0.05) the results compared with the base extenders without additives or just with glycerol. The sperm parameters assessed decline slowly from 0 to 48 h, with a sharp decline (p < 0.05) at 72 h of preservation. In conclusion, UHT and INRA‐96® were similar as base extenders, and the addition of 5% egg yolk plus 2% glycerol or just 5% egg yolk improved the quality of ram semen preserved at 5°C, at least for 48 h. The combination of egg yolk–glycerol might provide extra protection in case of fluctuation of temperatures below 5°C, commonly seen under field conditions.  相似文献   

5.
The ability to ship cooled stallion sperm for subsequent freezing at a facility specializing in cryopreservation would be beneficial to the equine industry. Stallion sperm has been centrifuged, cooled to 5 degrees C for 12 h, and frozen without a detrimental effect on motility in a previous study; however, no fertility data were available. Experiment 1 compared the post-thaw motility of sperm cooled for 18 h at 15 or 5 degrees C at either 400 or 200 x 10(6) sperm/mL and then frozen. Storage temperature, sperm concentration, or the interaction of temperature and concentration had no effect on total (TM) and progressive motility (PM) after cooling. Post-thaw TM and PM were higher for control than (P < 0.05) for treated samples. There was no difference in post-thaw TM and PM due to temperature or concentration. Experiment 2 further evaluated procedures for cooling before freezing. Ejaculates were either cooled to 5 degrees C for 18 h and centrifuged, centrifuged at room temperature and then cooled to 5 degrees C for 18 h before freezing, or centrifuged and frozen immediately (control). There was no difference among treatments on post-thaw TM or PM. In Exp. 3, mares were inseminated with semen that had been extended in skim milk-egg yolk without glycerol, centrifuged, resuspended at 200 x 10(6) sperm/mL, cooled to 5 degrees C for 18 h, and then frozen or not cooled for 18 h before freezing (control). Pregnancy rates did not differ for mares receiving semen cooled and then frozen (21 of 30, 70%) or semen frozen directly without prior cooling (16 of 30, 53%). In summary, a procedure was developed for cooling stallion sperm for 18 h before freezing without a resultant decrease in fertility.  相似文献   

6.
Ram seminal plasma increases the fertility of frozen-thawed ram spermatozoa deposited into the cervix. The aim of the current study was to compare the effect of ram seminal plasma to that of bull seminal plasma, dog prostatic fluid, protein-free TALP TrilEq (Triladyl with 0.5 mt of Equex STM paste added to each 100 mt) and heat-treated skim milk on longevity and percentages of progressively motile and aberrantly motile frozen-thawed ram spermatozoa. Three ejaculates from each of 6 rams were extended in TrilEq, pooled and frozen in straws as a single batch per ram. One hundred and eight straws (3 straws from each ram for each fluid) were thawed in random order. Once thawed, a straw was emptied into a tube with 0.85 ml of the appropriate fluid at 37 degrees C and kept at that temperature for 6 h. Motility was assessed at x200 magnification immediately (time zero) and 2, 4 and 6 h after thawing. Progressive motility decreased from each time to the next (P < 0.05) and was 39.0 % (0 h), 26.0 % (2 h), 19.6 % (4 h) and 12.6 % (6 h); SEM 1.24, n = 108 for each group. Ram seminal plasma resulted in higher progressive motility than bull seminal plasma, lower than milk, and similar to the other fluids. Ram seminal plasma resulted in lower aberrant motility than protein-free TALP and similar aberrant motility to other fluids. The effect of ram seminal plasma and dog prostatic fluid was very similar. The effect of ram seminal plasma on the fertility of frozen-thawed ram spermatozoa deposited into the cervix is not due an exceptionally beneficial effect on the motility of spermatozoa.  相似文献   

7.
The standard procedure of artificial insemination with fresh equine spermatozoa involves short‐term storage (to 48 h at 5°C). This procedure is accompanied by a gradual loss of sperm viability. The aim of this study was to investigate whether the X/Y ratio of equine spermatozoa is affected by short‐term storage and the swim‐up procedure. We used a standard protocol, for short‐term storage (0, 24 and 48 h at 5°C) of stallion semen diluted in the commercial extender EquiPro? (Minitüb GmbH, Tiefenbach, Germany). After each set‐up storage period, the motile fraction of sperm cells was selected by the swim‐up method. The X/Y ratio was evaluated by fluorescence in situ hybridization (FISH) in the fresh, non‐selected sperm, and in motile spermatozoa selected after each of the storage periods. Molecular probes for the equine chromosomes X and Y were used. The X/Y ratio in all sperm samples analysed in this study (fresh and stored) was not different from the theoretical 1 : 1 value. The incidence of chromosomally abnormal sperm cells in the fresh (0.28%) and motile (0.13%) sperm samples was not significantly different. The two approaches (sperm storage up to 48 h and the swim‐up procedure) applied to this study did not affect the X/Y ratio in the motile fraction of equine spermatozoa. This finding does not conform to phenomena described for human and cattle. For this reason, the finding may imply species‐related differences.  相似文献   

8.
A 4-year-old Basque Shepherd male dog was presented for breeding soundness evaluation after the dog failed to impregnate the three bitches he had mated. Clinical examination showed no anomaly of the reproductive system. Semen evaluation showed normal sperm count (640 x 10(6)), 80% had progressively motile spermatozoa, and 96% had morphologically abnormal sperm of which 84% had proximal cytoplasmic droplet and 12% had proximal droplet plus other anomaly. A zona pellucida-binding assay, using canine oocytes derived from frozen-thawed ovaries, was performed in order to investigate the zona-binding ability of dog spermatozoa with proximal cytoplasmic droplets. For the zona pellucida-binding assay, ovaries were thawed and minced in phosphate-buffered saline + 0.4% bovine serum albumin, the oocytes recovered were divided into two groups of 35-40 oocytes to be, respectively, used with the infertile dog and with a control fertile dog. Spermatozoa were capacitated in Canine Capacitating Medium (CCM) at 38.5 degrees C and 5% CO(2) in air for 2 h before oocyte insemination. Groups of five to six oocytes placed in 45 microl droplets of CCM were incubated for 1 h. Afterwards, 5 microl of CCM containing 25,000 spermatozoa were added to each droplet and co-incubated for 2 h before fixation and evaluation of the complexes. After oocyte insemination, sperm motility and viability were evaluated: the sample from the infertile dog had 85% sperm motility with fast and linear progressive movement, and sperm viability of 92%. The sample from the control dog showed 40% sperm motility with fast and highly curvilinear and erratic movement, high degree of sperm agglutination and sperm viability of 32%. For the infertile dog the mean number of bound spermatozoa/oocyte was 0.33 whereas for the control dog it was 1.80. It was concluded that dog sperm with proximal cytoplasmic droplets seem to lack normal capacitating ability in vitro, and consequently, they may have reduced capacity to bind to the zona pellucida of canine oocytes.  相似文献   

9.
The spermiograms of 17 bulls were studied and 160 ejaculates were subjected to the thermoresistance test (38 degrees C) to evaluate sperm survival after thawing. After the first insemination of 10 682 cows, statistically significant differences were found in the fertilizing capacity of the ejaculates with various values of the thermo-resistance test. The best sperm fertilizing capacity was obtained in the ejaculates which retained progressive movement in 40% of the spermatozoa after two hours of exposure to the thermoresistance test. Out of the 1496 cows inseminated, 971 (i.e. 64.9%) got in calf, whereas after the insemination of 4216 cows with semen where only 30% of spermatozoa moved progressively at the end of the test, the number of pregnant dams was 2403, i.e. 56.98%; this difference is statistically significant (p0.05). At a lower sperm activity in the test the fertility after the first insemination was even lower. Although there was some difference in the individual fertility of bulls (54 to 67%), a positive relationship between the results of the thermoresistance test and fertility was recorded in all bulls.  相似文献   

10.
Damage occurring to spermatozoa during cryopreservation results in a loss of motile cells and cells that are functionally normal, compared with fresh sperm samples. Treating bull sperm with cholesterol-loaded cyclodextrins (CLC) before cryopreservation results in increased sperm cryosurvival. However, in previous studies, CLC were always added to sperm samples that had been highly diluted. The aim of this study was to develop a procedure for adding CLC to whole bull ejaculates that would optimize sperm cryosurvival. Adding 2 or 4 mg of CLC/120 x 10(6) sperm to sperm samples ranging in concentration from 120 to 2,000 x 10(6) sperm/mL resulted in greater (17 to 28 percentage points; P < 05) numbers of live cells compared with control samples (no CLC treatment), regardless of the sperm concentration, except for samples at 120 x 10(6) sperm/mL treated with 4 mg of CLC. Incubating sperm with CLC at 23 or 37 degrees C before cryopreservation resulted in similar sperm cryosurvival. The cooling rate used to cryopreserve CLC-treated cells did not affect sperm cryosurvival. Finally, adding CLC to undiluted ejaculates (2 mg of CLC/120 x 10(6) sperm) resulted in greater percentages of live sperm compared with the control samples (62 vs. 45%; P < 0.05), although the percentages of motile sperm were similar for both CLC-treated and control samples (58%). In conclusion, bull sperm cryo-survival can be improved if spermatozoa are treated with CLC before freezing. In addition, CLC can be added to fresh ejaculates at either 23 or 37 degrees C. This technique is simple, practical, and can be easily integrated into current cryopreservation protocols.  相似文献   

11.
Assisted sperm morphometry analysis (ASMA) was used in this study to determine the effects of cryopreservation on bull spermatozoa distribution in morphometrically distinct subpopulations. Ejaculates were collected from five bulls and were divided. One portion was diluted at 30 degrees C in a skim milk-egg yolk medium, containing glycerol. A microscope slide was prepared from single extended sperm samples prior to freezing. The remainder of each sample was frozen in nitrogen vapours. After thawing, sperm smears were prepared as described above. All slides were air dried and stained with Hemacolor. The sperm-head dimensions for a minimum of 200 sperm heads were analysed from each sample by means of the Sperm-Class Analyser (SCA), and the mean measurements recorded. Our results showed that applying the ASMA technology and multivariate cluster analyses, it was possible to determine that three separate subpopulations of spermatozoa with different morphometric characteristics coexist in bull ejaculates (large, average and small spermatozoa). The mean values of each sperm head dimension among the three subpopulations of spermatozoa were significantly different (p < 0.001). Besides, there were significant (p < 0.001) differences in the distribution of these three sperm subpopulations between fresh and thawed samples. Thus, the percentage of representation of the subpopulation that includes those spermatozoa whose dimensions are the biggest, decreased from 52.06% in extended fresh samples to 15.51% in the thawed ones. Contrarily, the percent of representation of the subpopulation containing the smallest spermatozoa, increased from 8.70% in extended fresh samples to 34.04% in the thawed ones. In conclusion, the present study confirms the heterogeneity of sperm head dimensions in bull semen, heterogeneity that vary through the cryopreservation procedure.  相似文献   

12.
A study was conducted to assess viability and mitochondrial status of boar spermatozoa stored at 5 degrees C and 16 degrees C. Gel-free ejaculates, collected from 3 mature boars, were extended in a standard diluent (K3) supplemented with a low-density lipoprotein fraction (LDF) isolated from egg yolk, and stored for 96 h at 5 degrees C and 16 degrees C. Motility analysis was conducted after semen dilution (D0) and on D1-D4 of storage. A double staining method, rhodamine 123 (R123) and propidium iodide (PI), was used to assess sperm viability and mitochondrial status. Sperm viability was also assessed using Hoechst 33,258 (H33258) stain. In fresh semen samples, the percentage of motility was significantly correlated with the percentage of viable spermatozoa with functional mitochondria (R123-PI), viable spermatozoa determined by H33258 staining and ATP content (r = 0.88, p < or = 0.01; r = 0.69, p < or = 0.05; r = 0.77, p < or = 0.01, respectively). The ATP content was also positively correlated with the percentage of viable spermatozoa with functional mitochondria (r = 0.76, p < or = 0.01). Sperm cells progressively lost motility, viability and mitochondrial capacity when stored in the supportive media at 5 degrees C and 16 degrees C. Motility estimates were lower (p < or = 0.05) than the percentage of viable spermatozoa with functional mitochondria during storage in K3 and LDF-based diluents on D4 and D3-D4, respectively. Deterioration in motility and membrane integrity was less marked in spermatozoa stored in LDF-based diluents. Spermatozoa doubly-stained with R123-PI appeared to possess some functional mitochondria, particularly in LDF-based diluent semen. Estimates of sperm viability, as determined by R123-PI staining, were equivalent (p > or = 0.05) to estimates made using H33258 staining. A decrease in mitochondrial activity, as measured by R123 uptake, was accompanied by lower ATP content in spermatozoa stored in K3 and LDF-based diluents after 48 h and 72 h of storage, respectively. Fluorometric measurements of viability and mitochondrial status of boar spermatozoa during liquid storage seem to provide reliable information about the sperm functional membranes.  相似文献   

13.
Flow cytometry sorting of spermatozoa using fluorescence dye Hoechst 33342 is the only effective sex selection methodology validated in numerous laboratories. This study was carried out to determine the effect of Hoechst 33342 on the motility and fertility of stained boar spermatozoa. Experiment 1 evaluated motility parameters (percentage of motile spermatozoa, velocity, angularity and oscillation) of boar spermatozoa stained with Hoechst 33342 by a computer‐aided sperm analysis (CASA) instrument. Spermatozoa (30 million/ml) were divided into five treatment groups and stained during 1 h at 35°C with 9, 18, 27, 60 and 90 μM of H33342. There were no differences in sperm motility patterns nor percentages of motile spermatozoa incubated in the presence of 9, 18 or 27 μM. Percentage of motile spermatozoa and motility parameters decreased significantly (p < 0.05) at 60 μM of Hoechst 33342. Spermatozoa were immotile at concentration of 90 μM. In experiment 2, pregnancy rates, farrowing rates and litter size from sows (n = 275) artificially inseminated (AI) with either Hoechst 33342 stained (27 μM) or unstained (control) spermatozoa were determined. Sows inseminated with stained spermatozoa had no significant lower pregnancy rate (88.33%) as compared with controls (90.32%). Staining neither affected farrowing rates (85.0 vs 87.7%) nor total number of piglets born (10.56 ± 0.32 vs 10.47 ± 0.24, stained and controls, respectively). No phenotypical abnormalities were registered among the newborn piglets. The data suggest that incubating spermatozoa with Hoechst 33342 at levels required for X‐ and Y‐bearing chromosome sperm sorting, does not impair sperm viability or their fertility after AI.  相似文献   

14.
Cryosurvival of cells is reduced if the cooling rate used is suboptimal. If cells cool too rapidly, intracellular water will freeze, causing intracellular ice crystals. However, if spermatozoa are cooled too slowly, excessive cellular dehydration occurs, causing irreversible damage to cellular compartments. In addition, cryoprotectants are added to the freezing diluent to protect cells from damage during cryopreservation. This study was conducted to determine the optimal cooling rate for stallion spermatozoa frozen in the presence of three different cryoprotectants. Spermatozoa were frozen in a skim milk, egg yolk diluent containing 4% glycerol, and ethylene glycol or dimethyl formamide at 10 different cooling rates ranging from 5°C/min to 50°C/min. The percentage of viable spermatozoa was higher for spermatozoa cooled at 10°C/min than at 50°C/min (P < .05). Spermatozoa frozen using glycerol as the cryoprotectant had higher percentages of motile and progressively motile spermatozoa compared with spermatozoa frozen using the other two cryoprotectants (P < .05). In conclusion, the cryosurvival of stallion spermatozoa is similar when cooling rates of 5°C/min to 45°C/min are used, and when 4% cryoprotectant is used, glycerol is a more effective cryoprotectant than ethylene glycol or dimethyl formamide.  相似文献   

15.
As the preservation of the fertilizing capacity of rabbit spermatozoa for several days after semen collection remains a major target for the artificial insemination programs of rabbit breeding, a study was conducted to compare the efficacy of 5 or 15°C as holding temperature in lengthening the preservability of rabbit semen quality during 192 h of storage both in a solid (Cunigel) and a liquid (Tris-Citric acid-Glucose; TCG) extender. Six pooled semen samples (two ejaculates/male; two-three males/pool) were taken and made four aliquots: two aliquots were tenfold diluted with the TCG extender, whereas the other two were tenfold diluted with the Cunigel extender. One aliquot per diluent was stored at 5°C and the second one at 15°C. Sperm motility (light microscope), viability (SyBr-PI staining), plasma membrane functional integrity (Hypo-osmotic swelling test) and acrosome integrity (PSA-FITC staining) were recorded at 0, 48, 120 and 192 h of storage. In liquid-stored spermatozoa, mass motility and viability were significantly higher (p ≤ 0.05) in samples stored at 5°C than at 15°C at all the storage times; at 5°C resulted also higher (p ≤ 0.05) the percentages of both forward motility at 48 h and sperm functional integrity at 120 and 192 h of storage, whereas chilling temperature did not affect acrosome integrity. With the Cunigel extender, all the semen qualitative parameters were significantly higher in sample stored at 5 than 15°C over storage time (p ≤ 0.05); only acrosome integrity at 192 h was not different according to the chilling temperatures. In conclusion, 5°C were better than 15°C for the long-term storage of rabbit semen both in the TCG and Cunigel extender.  相似文献   

16.
Slow-cooled stallion spermatozoa, with and without seminal plasma removed by centrifugation, were diluted in Kenney's extender (KE) containing nonfat dry skim milk with glucose and antibiotics or in KE supplemented by adding a modified high-potassium Tyrode's medium (KMT). Four ejaculates from each of four stallions were collected and divided factorially across these four treatments. Percentage of motile sperm, path velocity, and linearity immediately after treatment (0 h) and after storage at 4 degrees C for 24, 48, and 72 h were evaluated objectively by use of a HTM-2030 sperm motility analyzer. Stallions were a significant source of variation (P less than .01) throughout. After sperm had cooled, effects of stallion, extender, centrifugation, and their interactions were all found to be significant (P less than .01). The motility at 0, 24, 48, and 72 h for centrifuged KE was 74, 47, 39, and 24%; for uncentrifuged KE was 76, 56, 50, and 37%; for centrifuged KMT was 76, 75, 72, and 64%; and for uncentrifuged KMT was 80, 50, 26, and 13%, respectively. The extender x centrifugation interaction, after 24, 48, and 72 h of storage, accounted for half or more of the variation. Whereas centrifugation of semen extended in KE seemed to be harmful to sperm, motility of sperm extended in KMT after centrifugation was remarkably conserved for 72 h and was superior to all other treatments (P less than .05). This extender is promising for preserving liquid stallion semen when it must be transported before use in artificial insemination.  相似文献   

17.
The present study aimed to compare cat sperm quality after thawing using two different temperatures (37 and 70°C) and to investigate the effects of post‐thaw dilution on the sperm quality and longevity of ejaculated cat spermatozoa. Six ejaculates of each of six male cats were collected using an electroejaculator (total 36 ejaculates). The semen was frozen in 0.25‐ml straws using a Tris egg yolk extender containing Equex STM paste. Four straws prepared from each ejaculate were thawed at four different occasions; (i) at 37°C for 15 s, (ii) at 37°C for 15 s and diluted 1 : 2 with Tris buffer (v/v), (iii) at 70°C for 6 s, (iv) at 70°C for 6 s and diluted 1 : 2 with Tris buffer (v/v). The percentages of motile spermatozoa, the scores of progressive motility, the percentages of spermatozoa with intact plasma membrane (using SYBR‐14/EthD‐1 stains) and intact acrosome (using fluorescein isothiocyanate conjugated peanut agglutinin/propidium iodide stains) were evaluated in fresh semen at 0, 2, 4 and 6 h after thawing. The thawing temperature had no effect on any sperm parameters throughout the incubation period (p > 0.05). The dilution after thawing improved sperm motility, progressive motility and acrosome integrity (p < 0.05). The thawing of cat spermatozoa and subsequently diluting with Tris buffer resulted in an immediate (at 0 h) overall (combined over temperature) percentage of motile sperm of 64.8 ± 10.7 (mean ± SD), a score of progressive motility of 4.0 ± 0.5, a percentage of spermatozoa with intact plasma membrane of 64.4 ± 12.1 and intact acrosome of 44.8 ± 20.2. In conclusion, frozen cat semen can be thawed either at 37 or 70°C and post‐thaw dilution is recommended to reduce the toxic effect of some ingredients in the extender during post‐thaw incubation.  相似文献   

18.
We previously reported that skim milk (SM) is an effective cryoprotectant for cryopreservation of canine spermatozoa instead of egg yolk (EY), which is the conventional cryoprotectant. In this study, the fertilizing ability and practical use of frozen canine spermatozoa prepared with SM were evaluated by transcervical insemination. Frozen‐thawed spermatozoa were inseminated one to four times on days 2–9 after the LH surge. In SM group, a single transcervical insemination (TCI) on Day 5 led to higher delivery rate (83%) than any other days (33%–50%) post‐LH surge. In EY group, delivery rate in double TCI on days 5 and 6 (71%) was higher compared to any other experimental groups (0%–44%). Regardless of single or double, TCI on Day 5 or Day 6 led to higher litter sizes in SM or EY groups, respectively. The breeding efficiency and litter size of single TCI on Day 5 (4.2) and double TCI on Day 5 and Day 6 (3.7) were significantly higher than in the other experimental groups in SM and EY groups, respectively (p < .05). These findings suggest that skim milk is a suitable alternative to egg yolk for cryopreservation of canine spermatozoa, and the suitable timing for insemination might be on Day 5 post‐LH surge.  相似文献   

19.
Cooled stallion semen has a short viable life, which ranges with acceptable motility and viability from 24 up to 48 hours. The purpose of this study was to compare the effects of storage pH, the ability of three different zwitterionic buffers, and cholesterol-loaded cyclodextrins (CLC) to preserve the motility and integrity of stallion sperm cooled to 5°C for 48 hours. Fourteen ejaculates were collected and split to receive CLC or not (control group). After incubation, each sample was split into six subsamples and diluted in KMT extender containing 4-(2-hydroxyethyl)piperazine-1-ethanesulfonic acid (HEPES), N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid (BES), or 2-(N-morpholino)ethanesulfonic acid (MES) buffers, and the final pH was adjusted to either 7.0 or 6.6, totalizing 12 experimental groups as a function of CLC, buffer, and pH variables (2 × 3 × 2 factorial). The motility parameters and integrity of plasma and acrosome membranes (live cell index) were determined using computer-automated semen analysis and epifluorescence microscopy at 3, 6, 24, and 48 hours of cooling period. According to results, pH was not a significant source of variation for motility and live sperm over different cooling periods. However, samples diluted in BES exhibited higher progressive motility within 3 hours and higher percentages of total motile cells after 48 hours of incubation at 5°C (P < .05). After 24 hours of storage, CLC-treated sperm samples presented higher motility than control group (P < .05), and after 48 hours of incubation, CLC-treated sperm exhibited higher percentages of live, motile, and progressively motile sperms (P < .05). We inferred that equine semen diluted in KMT containing BES as buffer and CLC treatment improve the equine sperm survival during storage at 5°C for 48 hours.  相似文献   

20.
Flow cytometrically sex sorted spermatozoa are reduced in their fertilizing capacity, particularly when stored either in cooling extender or after freezing in liquid nitrogen. So far, preservation methods for sorted spermatozoa have differed only marginally from procedures used for unsorted semen. In the present study, a TRIS extender was modified to balance major cell damage caused by the sorting process and by liquid storage of the sorted spermatozoa. The new extender, containing a combination of antioxidants (AO) and bovine serum albumin (BSA), significantly increased the lifespan and fertilizing capacity of sex sorted spermatozoa. No significant differences were observed between unsorted controls and sorted samples for motility and status of sperm membranes as tested by fluorescein-isothiocyanat-peanut agglutinin/propidium iodide (FITC-PNA/PI). Acrosome integrity of spermatozoa was significantly better when semen was stored at 15 degrees C for 24 and 48 h in an extender containing AO with or without BSA as compared with controls (p < 0.05). There were no significant differences, in pregnancy rates of heifers inseminated at a natural oestrus, between unsorted controls (16/24, 66.7%) and both sorted groups (AO + BSA: 18/31, 58.1% and AO-BSA: 12/22, 54.5%). Additionally, it was shown for the first time that artificial insemination (AI) with liquid sexed bull spermatozoa stored for 72 h after sorting can result in pregnancy rates similar to AI with non-sorted semen.  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