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1.
Colloid centrifugation of boar semen has been reported sporadically for at least the last two decades, beginning with density gradient centrifugation (DGC) and progressing more recently to single layer centrifugation (SLC). Single layer centrifugation through a species-specific colloid has been shown to be effective in selecting the best spermatozoa (spermatozoa with good motility and normal morphology) from boar sperm samples. The method is easier to use and less time-consuming than DGC and has been scaled-up to allow whole ejaculates from other species, e.g. stallions, to be processed in a practical manner. The SLC technique is described, and various scale-up versions are presented. The potential applications for SLC in boar semen preservation are as follows: to improve sperm quality in artificial insemination (AI) doses for 'problem' boars; to increase the shelf-life of normal stored sperm samples, either by processing the fresh semen before preparing AI doses or by processing the stored semen dose to extract the best spermatozoa; to remove pathogens (viruses, bacteria), thus improving biosecurity of semen doses and potentially reducing the use of antibiotics; to improve cryosurvival by removing dead and dying spermatozoa prior to cryopreservation; to select spermatozoa for in vitro fertilization. These applications are discussed and practical examples are provided. Finally, a few thoughts about the economic value of the technique to the boar semen industry are presented.  相似文献   

2.
The aim of this study was to determine whether there was an increase in pregnancy rates when frozen-thawed stallion semen was processed by single layer centrifugation (SLC) through a colloid before insemination. In addition, changes in semen parameters, including motility, were determined before and after SLC. Twenty light-horse mares (aged 3-16 years) and one Thoroughbred stallion (aged 16 years) having average fertility with fresh and cooled semen (>50% per cycle) and displaying a postthaw motility of >35% were used. Control mares were inseminated using 4- × 0.5-mL straws (200 × 106/mL) of frozen-thawed semen. Treatment mares were inseminated with 4 × 0.5 mL of frozen-thawed semen after processing by SLC. Pregnancy rates were compared using Fisher exact test, and continuous parameters were evaluated by a Student t test. The pregnancy rates at day 14 were not different for the mares inseminated with control versus SLC-processed semen, despite the difference in sperm number (171 × 106 ± 21, 59 × 106 ± 25 progressively motile sperm). After frozen-thawed semen was processed by SLC, the percentage progressively motile sperm improved (P < .05), and SLC processing resulted in a 21.8% recovery of spermatozoa. In summary, centrifugation of frozen-thawed semen through a single layer of colloid increased the percentage of motile spermatozoa, but did not improve pregnancy rates after deep horn insemination.  相似文献   

3.
The purposes of this study were to examine the relationship between male artificial insemination (AI) fertility and sperm acrosomal conditions assessed by new and conventional staining techniques and to identify possible reproductive dysfunctions causing low conception rates in AI using frozen-thawed spermatozoa with poor acrosomal conditions in Japanese Black bulls. We investigated individual differences among bulls in the results concerning (1) acrosomal conditions of frozen-thawed spermatozoa as assessed by not merely peanut agglutinin-lectin staining (a conventional staining technique) but also immunostaining of acrosomal tyrosine-phosphorylated proteins (a new staining technique), (2) routine AI using frozen-thawed spermatozoa as assessed by pregnancy diagnosis, (3) in vivo fertilization of frozen-thawed spermatozoa and early development of fertilized eggs as assessed by superovulation/AI-embryo collection tests and (4) in vitro fertilization of frozen-thawed spermatozoa with oocytes. The percentages of frozen-thawed spermatozoa with normal acrosomal conditions assessed by the abovementioned staining techniques were significantly correlated with the conception rates of routine AI, rates of transferable embryos in superovulation/AI-embryo collection tests and in vitro fertilization rates. These results are consistent with new suggestions that the distribution of acrosomal tyrosine-phosphorylated proteins as well as the acrosomal morphology of frozen-thawed spermatozoa are AI fertility-associated markers that are valid for the prediction of AI results and that low conception rates in AI using frozen-thawed spermatozoa with poor acrosomal conditions result from reproductive dysfunctions in the processes between sperm insemination into females and early embryo development, probably failed fertilization of frozen-thawed spermatozoa with oocytes.  相似文献   

4.
The aim of this study was to evaluate the effect of antioxidant catalase (CAT) and superoxide dismutase (SOD) in semen extender on motility, viability and acrosomal integrity of frozen-thawed cat spermatozoa. Semen was collected by using an artificial vagina from five domestic cats (two ejaculates/cat). Spermatozoa were diluted in egg yolk Ttris-fructose citrate solution (EYT-FC) without glycerol and cooled at 4°C for 1 h, then diluted further with EYT-FC with glycerol (7% final concentration) and 400 IU/ml of CAT (treatment 1) or SOD (treatment 2) or without antioxidants (control). Before freezing using a styrofoam box, diluted spermatozoa filled in 0.25-ml straws were equilibrated for 1 h at 4°C. After thawing, spermatozoa were assessed for motility, viability and acrosomal integrity. Cryopreservation significantly impaired sperm motility, viability and acrosomal integrity (p   <   0.05). However, motility, viability and acrosomal integrity of frozen-thawed cat spermatozoa in the EYT-FC with CAT, SOD and without the antioxidants were not significantly different. The average percentages of spermatozoa motility after thawing compared between control, treatment 1 and treatment 2 group were 43.5 ± 3.2, 42 ± 4.1 and 38 ± 4.5; for viability: 44.8 ± 3.5, 50.6 ± 5.7 and 47.1 ± 4.1 and for acrosomal integrity: 45 ± 3.5, 44.9 ± 3.4 and 44.4 ± 3.3, respectively. In conclusion, adding CAT and SOD to EYT-FC did not improve motility, viability and acrosomal integrity in cryopreserved cat spermatozoa.  相似文献   

5.
The objective was to investigate whether it is possible to improve the quality of stallion semen, with respect to sperm morphology and chromatin integrity, both of which have been linked to fertility, using either density gradient centrifugation (DGC) or a new method, hereby named single layer centrifugation (SLC). The two methods of colloidal centrifugation were evaluated using 38 ejaculates from 10 stallions. Sperm morphology, subjective motility and sperm chromatin integrity were compared in uncentrifuged samples and in centrifuged sperm preparations. The proportion of morphologically normal spermatozoa varied between stallions (p < 0.001) and was increased by both methods of colloidal centrifugation (median value before centrifugation 67.5%; after SLC 78%; after DGC 77%; p < 0.001). The incidence of certain abnormalities was reduced, e.g. proximal cytoplasmic droplets were reduced from 12.9% to 8.8% (p < 0.001), and mid-piece defects from 5.3% to 1.4% (p < 0.05). Similarly, sperm motility and chromatin integrity were significantly improved (p < 0.001), with no difference between the two centrifugation methods. Centrifugation through colloids can enrich the proportions of stallion spermatozoa with normal morphology and normal chromatin structure in sperm preparations. The new method, SLC, was as effective as DGC in selecting motile stallion spermatozoa with normal morphology and intact chromatin. SLC, being simpler to use than DGC, would be appropriate for routine use by stud personnel to improve stallion sperm quality in insemination doses.  相似文献   

6.
The aim of this work was to study the effects of cryopreservation on the binding and penetration of dog spermatozoa to the zona pellucida (ZP) by scanning electron microscopy (SEM). The sperm-rich fraction of six ejaculates from five dogs was divided into two aliquots and washed by centrifugation. One aliquot was processed as fresh control sample and the other aliquot frozen in Tris-fructose extender. Gamete interaction was assessed using in vitro matured bitch oocytes, which were co-incubated for up to 3 h. At hourly intervals after the start of co-incubation, in vitro fertilized (IVF) oocytes were processed by SEM. The results were analysed statistically using the anova test. Differences in binding and penetration of the spermatozoa to the ZP occurred; a lower proportion of oocytes with spermatozoa bound to ZP was observed using frozen sperm (p < 0.05) than with fresh sperm (61%, 57% and 53% vs 42%, 40% and 44% at 1, 2 and 3 h, respectively). The percentage of ZP penetration by fresh sperm was directly proportional to the time of co-incubation (9%, 25% and 34%; p < 0.05); in contrast, no differences were observed in the penetration rate with frozen-thawed sperm (21%, 17% and 21%). More acrosome reacted sperm were observed in frozen sperm than in fresh sperm on the surface of the ZP. The differences in the percentage of binding and penetration between fresh and frozen sperm during the co-culture could indicate that the time course of penetration is faster in frozen-thawed dog spermatozoa than in fresh sperm, but that fresh spermatozoa can penetrate more oocytes over a given period of time, which may be related to their reacted or non-reacted initial status.  相似文献   

7.
Reasons for performing study: A new, simpler, technique of colloidal centrifugation has recently been developed, designated single layer centrifugation (SLC). This technique requires evaluation by comparison with a density gradient for its ability to select the best quality spermatozoa and its practicality of use on studfarms. Objective: To compare the effect of 2 methods of colloidal centrifugation, density gradient centrifugation and single layer centrifugation, on stallion sperm motility, yield and survival, using freshly collected extended stallion semen. Methods: Aliquots of extended stallion semen from 10 stallions (38 ejaculates) were processed by the 2 methods of colloidal centrifugation. For both uncentrifuged and centrifuged samples, sperm yield was calculated and subjective sperm motility assessed over several days to provide an estimate of sperm survival. Some stored semen samples, held at 4°C overnight, were also available for testing. Results: For fresh, extended semen, a similar recovery yield of motile spermatozoa was seen for the 2 methods of preparation for single layers and density gradients, respectively. Sperm motility and survival rate were significantly improved by colloidal centrifugation compared to unprocessed ejaculate, without any significant difference between methods (SLC vs. gradient). However, the yield was reduced by 18–20% when cold‐stored semen was used for centrifugation compared to fresh semen; and more variation between ejaculates was observed than for fresh ejaculates. Again, sperm motility and sperm survival were improved in the centrifuged sperm preparations compared to stored, unprocessed ejaculates. Potential relevance: The 2 colloid centrifugation techniques produce equivalent sperm preparations in terms of sperm quality. However, the SLC method would be more practical and convenient for use in the field.  相似文献   

8.
The present study attempted to select the subpopulation of stallion spermatozoa that best survived a conventional freezing and thawing procedure, using centrifugation of post-thawed semen samples through a single layer of a glycidoxypropyltrimethoxysilane-coated silica colloid with a species-specific formulation (Androcoll-E™). After freezing and thawing, four sperm subpopulations were identified, listed as FT1 to FT4. While subpopulations FT1 and FT2 were characterized by low sperm velocity, high velocities characterized the ones called FT3 and FT4. The single-layer centrifugation (SLC)-handled sperm sample was enriched in subpopulation FT3, reaching a proportion of 82.6% of the present spermatozoa, in contrast with the non-filtered control post-thawed semen, where this sperm subpopulation only accounted for 16.3% of the total. It is concluded that in the equine industry, the SLC is a practical, easy-to-perform approach to improve the quality of equine frozen–thawed semen samples.  相似文献   

9.
Straws of sex‐sorted sperm are usually packaged at a low concentration (e.g., ~2.1 × 106 sperm/ml) and cost significantly more than unsorted conventional semen from the same sire. In order to maximize the efficiency of using sex‐sorted sperm under in vitro fertilization conditions, the selection of an appropriate sperm separation technique is essential. In this study, the effect of using different silane‐coated silica colloid dilutions and layering configurations during centrifugation of sex‐sorted sperm was examined over an extended period of incubation time. Sperm recovery and viability after centrifugation using the colloid separation technique were measured along with several sperm motility parameters using CASA. For this purpose, frozen and thawed sex‐sorted sperm samples were centrifuged using mini‐volume single‐layer (40%, 60% and 80%) and mini‐volume two‐layer (45%/90%, 40%/80% and 30%/60%) separation configurations using PureSperm®. A single layer of 40% PureSperm® recovered significantly more sex‐sorted sperm (78.07% ± 2.28%) followed by a single layer of 80% PureSperm® (68.43% ± 2.33%). The lowest sperm recovery was obtained using a two‐layer PureSperm® dilution of 45%/90% (47.57% ± 2.33%). Single‐layer centrifugation recovered more sorted sperm (68.67% ± 1.74%) than two layer (53.74% ± 1.74%) (< .0001). A single layer of 80% PureSperm® exhibited the highest sorted sperm viability (72.01% ± 2.90%) after centrifugation (< .05). The mini‐volume single layer of 80% PureSperm® was determined to be an effective alternative to a two‐layer centrifugation configuration for sex‐sorted sperm selection. In addition, single‐layer colloid dilution of 80% performed either as well as or significantly outperformed the other treatments, as well as the control, with regard to motility (MOT) for all time periods of analysis.  相似文献   

10.
Semen from a Western Finncattle bull exhibiting a highly polymorphic spermiogram was processed by colloid centrifugation using Androcoll‐B, a species‐specific silane‐coated silica colloid. In the first experiment, Single Layer Centrifugation (SLC) was used to identify which density colloids were needed to separate different cell populations. Colloids of the two chosen densities were then used in a density gradient resulting in two sperm subpopulations, one containing nearly all normally sized spermatozoa and the other enriched for the macrocephalic spermatozoa. Microcephalic spermatozoa did not appear in either of the selected subpopulations. Using a combination of SLC and DGC with this species‐specific colloid, it was possible to separate the spermatozoa into different subpopulations, that is, a subpopulation containing nearly all normally sized spermatozoa, and another one enriched for the macrocephalic spermatozoa. Thus, colloid centrifugation could be used to select sufficient normal spermatozoa from a highly polymorphic ejaculate for AI, if desired.  相似文献   

11.
The objective of this study was to optimize recovery and cryopreservation of epididymal sperm from plains bison, as a model for wood bison. In Phase 1, cauda epididymides were recovered from bison (n = 14) immediately after slaughter, minced and incubated in Sp-TALPH buffer for 3 h at 36°C. The resulting sperm suspensions were cryopreserved in Triladyl®, using a protocol for bovine semen. In Phase 2, epididymal sperm were cryopreserved in either Triladyl® or Andromed®. The mean (±SD) estimated number of sperm recovered was 468 ± 207 × 106. There was an increase (p < 0.05) in the proportion of sperm with normal morphology between initial recovery and after extension (52.4 ± 4.6 vs 69.7 ± 2.4%), with a concurrent decrease (p < 0.05) in the proportion of sperm with distal droplets. Median values for progressively motile sperm in post-thaw samples (60%) were lower (p < 0.05) than that after extension or after chilling (70% for both). The mean percentages of viable sperm and of sperm with an intact acrosome were lower (p < 0.05) for frozen-thawed samples (38.7 ± 2.8 and 85.2 ± 1.1) compared with extended (66.2 ± 2.2 and 92.4 ± 0.9) or chilled (63.7 ± 2.5 and 90.0 ± 1.0) samples. Rates of cleavage, morulae and blastocyst production were not significantly different for chilled (70.9, 38.7 and 8.0%) vs post-thaw sperm (73.0, 46.0 and 6.3%). There was no significant difference between extenders for most sperm characteristics. In conclusion, we developed a functional protocol for the recovery and cryopreservation of epididymal sperm from plains bison, which may have implications for the genetic preservation of wood bison.  相似文献   

12.
Artificial insemination (AI) is one of the most widely used reproductive technologies, and there is considerably interest in commercializing this technology in camels. Storage of semen extender frozen (at -20 °C) is of considerable interest to scientists working with camels, as transportation of diluents at refrigeration temperature is not always possible given the hot, arid and remote conditions that dromedary camels exist in. Therefore, this study was conducted to compare the fertility of fresh camel semen, after dilution in fresh or frozen-thawed green buffer (GB), after AI into single and multiple ovulating female camels. No differences were observed in any sperm characteristics (motility, membrane integrity, acrosome integrity or morphology) when semen was diluted in fresh or frozen-thawed GB (p>0.05). Sperm motility was increased by dilution (fresh: 70.7 ± 4.9% and frozen: 68.8 ± 3.1%) compared with the motility of sperm in neat semen (35 ± 2.85%; p<0.05), and sperm motility changed from oscillatory to forward progressive after dilution. Pregnancy rates were higher (p<0.05) for single ovulating camels inseminated with semen diluted in fresh (72.7%) compared with frozen-thawed GB (27.3%), and fertilization rates were also higher (p<0.05) for multiple ovulating camels inseminated with semen diluted in fresh (83.3%) compared with frozen-thawed GB (11.1%). These results clearly demonstrate the detrimental effect of freezing and thawing semen diluent on the fertility of fresh camel semen. However, further studies are required to elucidate the mechanism responsible for this reduction in fertility. Moreover, these results demonstrate that the fertility of fresh camel semen diluted in fresh GB is high enough to be considered commercially viable.  相似文献   

13.
In order to improve boar sperm quality during frozen-thawed process, the influence of the presence of trehalose on success of cryopreservation of boar sperm were investigated. We evaluated freeze-thawing tolerance of boar spermatozoa in a base cooling extender with the addition of different trehalose concentrations (0, 25, 50, 100 and 200 m m ), and try to determine the optimum concentration of trehalose. We chose sperm motility, mitochondrial activity, acrosome integrity and membrane integrity as parameters to evaluate cryopreservation capacity of boar spermatozoa. We obtained the best results for 100 m m trehalose-supplemented extenders, with values of 49.89% for motility, 44.69% for mitochondrial activity, 66.52% for acrosome integrity and 44.61% for membrane integrity, while freeze-thawing tolerance diminished significantly for 200 . The synergic effect of trehalose and glycerol resulted in better cryosurvival of boar spermatozoa than that of a single cryoprotectant. In conclusion, when trehalose-supplementation was added up to 100 m m , trehalose confers a greater cryoprotective capacity to the extender, and the sperm motility, mitochondrial activity, membrane integrity and acrosome integrity parameters were significantly improved during frozen-thawed process.  相似文献   

14.
本实验目的是评价低密度脂蛋白(LDL)对冻融后猪精子DNA完整性及受精率的影响。结果表明:添加9%LDL处理组冷冻解冻后,精细胞DNA完整率(彗星长为13.21,尾长为10.28,尾部DNA(%)为16.54,尾矩为2.31)和卵裂率(43.12%)都与7%、8%和10%LDL处理组差异显著(P<0.05)。本实验表明LDL能显著提高冷冻解冻后猪精子DNA的完整性;也能显著改善冷冻解冻后猪精子体外受精(IVF)率。  相似文献   

15.
This study was designed to evaluate the effect of single layer centrifugation (SLC) and subsequent cold storage on stallion sperm capacitation‐like status and acrosome reaction. Three stallions were included in the study, with three ejaculates per stallion. The samples were examined 4, 24 and 72 h after collection, extension and SLC, with storage at 6°C. Sperm capacitation‐like status was investigated using the fluorescent dye chlortetracycline (CTC). There was no difference in capacitation‐like status between colloid‐selected and non‐selected spermatozoa. Sperm motility decreased significantly during cold storage, whereas the proportion of apparently capacitated spermatozoa increased. There was no change in the proportion of acrosome‐reacted spermatozoa. In conclusion, SLC through Androcoll?‐E does not adversely affect the capacitation‐like status of stallion spermatozoa, although it did increase with time during cold storage.  相似文献   

16.
Although several selection techniques are available for processing spermatozoa, only colloid centrifugation has been used to any extent in this field, starting with density gradient centrifugation and progressing more recently to single-layer centrifugation (SLC). SLC through a species-specific colloid has been shown to be effective in selecting spermatozoa with good motility and normal morphology from stallion semen. The method is easier to use and less time-consuming than density gradient centrifugation, and has been scaled-up to allow whole ejaculates to be processed in a practical manner. The potential applications of SLC in equine breeding are as follows: to improve sperm quality in artificial insemination doses for “problem” ejaculates, to increase the shelf life of normal sperm doses, to remove pathogens (viruses, bacteria), to improve cryosurvival by removing dead and dying spermatozoa before freezing or after thawing, to select spermatozoa for intracytoplasmic sperm injection, and to aid conservation breeding.  相似文献   

17.
In domestic cats, epididymal spermatozoa have lower initial motility and viability than ejaculated spermatozoa and it is possible that seminal plasma compounds are behind these effects. The aim of this study was to investigate whether co-incubation of post-thaw epididymal cat spermatozoa with seminal plasma was able to improve sperm quality. Epididymal cat spermatozoa from 11 cats were cryopreserved. After thawing, each sperm sample was divided into two aliquots, centrifuged and incubated with two different media; Tris buffer (control) or pooled seminal plasma (treatment). Sperm quality was observed at 0, 2, 4 and 6 h after incubation. The results demonstrated that all of the sperm parameters except acrosome integrity were lower in the treatment group compared to the control group (p < 0.05); the percentages of motility (46.4 ± 15.4 vs 40.0 ± 9.4), the scores of progressive motility (3.1 ± 0.4 vs 2.8 ± 0.5), the percentages of spermatozoa with intact plasma membrane (46.3 ± 9.7 vs 39.6 ± 8.9) and intact acrosome (36.5 ± 16.2 vs 32.9 ± 15.1), as well as at all time points. In conclusion, the seminal plasma seems less beneficial to the post-thaw epididymal cat spermatozoa than the Tris buffer.  相似文献   

18.
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   

19.
Artificial insemination (AI) subfertility is an indication of failure of AI with frozen-thawed sperm classified as normal by conventional semen examination. Recently, 8 AI-subfertile Japanese Black cattle (S1-S8) were identified using the routine AI test or in vivo fertilization test, which included AI with frozen-thawed sperm of superovulated females and subsequent non-surgical recovery of presumptive zygotes. In the present study, we assessed capacitation states and in vitro oocyte penetration of frozen-thawed sperm from these bulls to estimate causal factors of AI subfertility. Frozen-thawed sperm from 8 AI-subfertile (S1-S8) and 9 fertile (F1-F9, control) bulls were washed and then used for a chlortetracycline (CTC) staining assay and in vitro fertilization test. The CTC staining assay revealed that approximately 50% of the sperm from 4 of the AI-subfertile bulls (S5-S8) were prematurely progressing into the capacitation state immediately after washing and resuspension in a CaCl(2)-lacking medium. In contrast, most of the sperm from the fertile bulls and other AI-subfertile bulls (S1-S4) remained uncapacitated. Addition of CaCl(2) to the medium effectively promoted a spontaneous acrosome reaction in the sperm samples from the AI-subfertile bulls (S5-S8). Moreover, the in vitro fertilization test showed that rates of sperm penetration into oocytes were significantly lower in sperm samples from the AI-subfertile bulls (S5-S8) than in the control sperm samples from the fertile bulls (F2-F4 and F7-F9). It has previously been suggested that prematurely capacitated sperm undergo a spontaneous acrosome reaction possibly due to uncontrolled influx of calcium ion, and consequently they possess relatively lower in vitro fertilizing ability. It is therefore possible that premature capacitation of sperm used for AI is a causal factor of subfertility of male Japanese Black cattle and a potentially good marker for identification of subfertile bulls for removal from AI programs.  相似文献   

20.
At the time of AI following Ovsynch protocol, a total of 51 buffaloes were randomly divided in a first group (n = 30) subjected to conventional AI into the uterine body with 20 million non-sex sorted frozen-thawed spermatozoa, while a second group (n = 21) was inseminated near the utero-tubal junction (UTJ) ipsilateral to the ovary carrying the preovulatory follicle with 2.5 million live (4 million total) sex-sorted frozen-thawed spermatozoa. The semen used for flowcytometric sorting was collected and processed on a farm in Italy, and then shipped to a laboratory in Germany. Eleven buffaloes were inseminated with X-chromosome bearing spermatozoa and 10 with Y-chromosome bearing spermatozoa. Conception rates after conventional and UTJ inseminations were 43.3% (n = 13) and 42.8% (n = 9) respectively (p = 0.97). Eight of the nine foetuses obtained after insemination with sexed spermatozoa corresponded to the sex as predicted by the cell sorting procedure (five male and four female foetuses by ultrasound vs six male and three female foetuses by cell sorting). In conclusion, for the first time buffalo semen has been successfully subjected to procedures for flowcytometric sperm sorting and freezing. Low doses of sexed spermatozoa have been deposited near the UTJ giving conception rates similar to those of conventional AI with full dose.  相似文献   

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