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1.
ESR2 is involved in oestrogen-related apoptosis in cell cycle spermatogenesis but their effects have not yet confirmed in pig. Therefore, this study was aimed to investigate the association of ESR2 polymorphism with sperm quality and boar fertility traits and to analyse the ESR2 mRNA and protein expressions in boar reproductive tissues. DNA samples from 203 Pietrain (PI) and 100 Pietrain × Hampshire (PIHA) pigs with records of sperm quality [sperm concentration (SCON), motility (MOT), semen volume (VOL), plasma droplet rate (PDR) and abnormal spermatozoa rate (ASR)] and fertility [non-return rate (NRR) and number of piglet born alive (NBA)] traits were available. A SNP in coding region of ESR2 g.35547A>G in exon 5 was associated with MOT and PDR in the PI and with SCON, VOL, MOT and PDR in PIHA population. For mRNA and protein expression study, a total of six boars were divided into two groups with group I (G-I) and group II (G-II) where G-I characterized for relatively a better sperm quality according to the mean of two groups. mRNA expression was higher in brain and testis than that in all parts of epididymis. Both qRT-PCR and western blot analysis revealed that the ESR2 gene expression and protein expression were significantly higher in testis collected from G-II compared with that of G-I boars. Moreover, ESR2 protein localization in germ cell, Leydig and Sertoli cells, epithelial cells and spermatozoa was remarkable, which indicated the important role of ESR2 in spermatogenesis process. These results might shed new light on the roles of ESR2 in spermatogenesis as candidate for boar fertility, but still the lack of association across populations should be considered.  相似文献   

2.
Retinol-binding protein 4 (RBP4), androgen receptor (AR), relaxin (RLN), acrosin (ACR) and osteopontin (polymorphism in intron 6 named OPNin6; polymorphism in promoter region named OPNprom) were addressed as functional candidate genes for sperm quality and boar fertility and investigated for their association with sperm concentration, motility, semen volume per ejaculate, plasma droplets rate, abnormal spermatozoa rate as well as non-return rate and number of piglets born alive. Therefore 356 AI boars of the purebred Pietrain (PI) and crossbred Pietrain x Hampshire (PI x HA) were genotyped at these loci. Analysis of variance revealed significant associations of RBP4 (p < 0.05), ACR (p < 0.01), and OPNin6 (p < 0.05) with sperm motility. OPNin6 (p < 0.05) was also associated with number of piglets born alive. Moreover, AR (p < 0.05) and OPNprom (p < 0.05) were significantly associated with abnormal spermatozoa rate. For RLN (p < 0.01) there was evidence for effects on sperm volume and ACR significantly affected sperm concentration (p < 0.05) as well as non-return rate (p < 0.05). No significant effects of any locus on plasma droplets rate were observed.  相似文献   

3.
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4.
本试验旨在研究谷胱甘肽过氧化物酶6（glutathione peroxidase 6,GPx6）在大白公猪附睾细胞中的表达和定位,并探究其与公猪繁殖性能的相关性。选取15月龄的公猪和母猪各3头,取睾丸、附睾、前列腺、尿道球腺、精囊腺、卵巢和输卵管,提取蛋白,通过蛋白免疫印迹和免疫组化（IHC）检测组织和细胞中GPx6蛋白的表达和定位;根据评定大白公猪受精能力的数学模型,按照公猪配种胎次≥20胎、3次配种公猪为同一头的标准,筛选并采集符合要求的20头公猪精液,同时,统计相对应的1 279头母猪的生产成绩,计算得到公猪繁殖性能指标（包括窝产总仔数、窝产活仔数、分娩率和繁殖力）。提取精子蛋白和精清蛋白,通过BCA和ELISA检测精子和精清中GPx6蛋白的含量。使用SPSS软件的独立样本t检验及单因素方差分析（one-way ANOVA）,进行差异显著性分析,用双变量Pearson进行相关性分析,P<0.05表示差异或相关显著。结果表明,GPx6蛋白在附睾中高表达,IHC结果显示,GPx6蛋白在附睾的顶细胞、基底细胞、晕细胞、主细胞和精子中表达,在肌样细胞中不表达;精清蛋白中GPx6的含量是精子蛋白的7倍,精液中GPx6蛋白的含量与窝产活仔数、窝产总仔数呈负相关关系。结果提示,GPx6在附睾的顶细胞、基底细胞、晕细胞、主细胞和精子中表达,且其在精液中的含量会影响公猪的繁殖性能,这为GPx6对公猪受精能力影响的研究奠定了理论和试验基础。  相似文献   

5.
Chinese Erhualian pigs are known for prolificacy with distinct reproductive traits compared with Western commercial breeds. In this study, a four‐generation intercross resource population was constructed using White Duroc boars and Chinese Erhualian sows as founder animals, and a total of 14 male reproductive traits were recorded in 411 F2/F3 boars including the testis and epididymis weights, the seminiferous tubular diameter and spermatogenesis at 60, 90 and 300 days of age, semen characteristics, serum testosterone concentration and libido level at 300 days of age. The White Duroc–Erhualian boars showed remarkable segregations in the traits measured except for the seminiferous tubular diameter and had high ratio (13.9%) of the abnormality of spermatogenesis, providing a good experimental population for detecting quantitative trait loci affecting these male reproductive traits. Furthermore, the correlations among nine male reproductive traits at 300 days of age indicated that the testis weight and the body weight were strongly correlated with the sperm production, supporting the two traits as important parameters for boar selection to increase sperm production and ultimately improve boar fertility. The libido level in the White Duroc–Erhualian boars that was evaluated by a new and easily recorded scoring system showed a significant correlation with serum testosterone concentration. Yet, both libido and serum testosterone concentration were not correlated with the sperm production. Results of this study provided new information on the male reproductive physiology and genetics in Chinese Erhualian and White Duroc boars.  相似文献   

6.
本研究目的是评估不同处理对精子顶体素活性的影响以及顶体素活性、精液参数和体外受精间的联系.鲜精、稀释精液(1:1)和液相精液(17℃)的精子顶体素活性分别是5.27,4.28和4.41 mIU/106.冻精或液相精液保存4 d后顶体素活性显著下降(P＜0.05).公猪间液相精液顶体素活性和低渗膨胀精液百分数有显著的差异(P＜0.05).冷、热应激对精子顶体素活性没有影响.鲜精和冻精的顶体素活性与低渗膨胀精子百分数和顶体完整率呈正相关.不同种猪液相精液精子顶体素活性与体外受精率和随后的囊胚发育率相关性不大.因此建议顶体素活性与其它精子功能参数相结合才能精确预测精子受精力.  相似文献   

7.
The objective of this study was to investigate the effects of a preparation from herbal extracts (PHE) on libido and semen quality in breeding artificial insemination boars. Ten fertile boars were divided into control and experimental groups according to significant difference of libido. There were no differences in semen quality between groups. Animals were fed a commercial feeding mixture for boars. The feeding mixture for the experimental group was enriched with PHE, which was prepared from Eurycoma longifolia, Tribulus terrestris and Leuzea carthamoides. Duration of the experiment was 10 weeks. Samples of ejaculate were collected weekly. Libido was evaluated according to a scale of 0-5 points. Semen volume, sperm motility, percentage of viable spermatozoa, sperm concentration, morphologically abnormal spermatozoa, daily sperm production and sperm survival were assessed. Amounts of mineral components and free amino acids were analysed in seminal plasma. Significant differences were found in these parameters: libido (4.05 ± 0.22 vs 3.48 ± 0.78; p < 0.001), semen volume (331.75 ± 61.91 vs 263.13 ± 87.17 g; p < 0.001), sperm concentration (386.25 ± 107.95 vs 487.25 ± 165.50 × 10(3) /mm(3); p < 0.01), morphologically abnormal spermatozoa (15.94 ± 11.08 vs 20.88 ± 9.19%; p < 0.001) and Mg concentration (28.36 ± 11.59 vs 20.27 ± 13.93 mm; p < 0.05). The experimental group's libido was increased by 20% in comparison with the beginning of the experiment. Results of this study showed positive effect of PHE on libido and some parameters of boar semen quality.  相似文献   

8.
Although widely used in practice, visual motility assessment of boar spermatozoa is a very subjective method. The aim of this study was to compare the visual motility assessment of boar spermatozoa with two objective, automated systems, namely the Sperm Quality Analyzer (SQA-IIC) and the Hamilton-Thorne computer-based semen analyzer (HTR). In addition, concentrations as determined by the Burker counting chamber and HTR were compared. Motility of 30 semen samples from 30 different boars (22 Pietrain, seven Landrace boars and one Large White) was examined during three consecutive days, subjectively by two independent persons (visual motility assessment) and objectively with both automated systems. The use of the SQA-IIC and HTR for assessing boar sperm motility was evaluated and the repeatability of the measurements was estimated. The Sperm Motility Index (SMI), determined by SQA-IIC, and the percentage motile spermatozoa determined by the HTR showed a good correlation (r=0.71; p <0.05). The visual examination performed by Person 2 showed a good correlation with the SMI (r=0.81) and with the percentage of motile spermatozoa measured by the HTR (r=0.66) (p <0.05). There was a very poor correlation and a limited agreement between the visual assessments of both persons emphasizing the subjectivity of visual motility assessment. Nevertheless, motility scores of each person during the three consecutive days were highly correlated (r=0.67 and 0.72, p <0.05). The limits of agreement plots showed poor agreement between both persons and the HTR. The repeatability of measurements for most parameters evaluated by the HTR and by the SQA-IIC was good with coefficients of variation below 10%. In addition, for fertile Pietrain boars (n=22), reference values for the different HTR-parameters are presented showing a high curvilinear velocity (157.3 +/- 19.5 microm/s) and a low straightness and linearity of the movement of the spermatozoa (62.7 +/- 8.7 and 35.5 +/- 7.6%, respectively). Concentration as determined by the Burker counting chamber (56.0 +/- 16.8 x 10(6)/ml) was significantly higher compared with HTR measurement (37.6 +/- 7.7 x 10(6)/ml). The high number of counted cells and the low variation render the HTR concentration measurement more reliable. It can be concluded that visual motility assessment is highly subjective and should therefore be replaced by automated systems that allow for a more objective and detailed motility assessment of boar spermatozoa. In addition, based on the present results, highly repeatable results were obtained by the SQA-IIC and especially by the HTR.  相似文献   

9.
Three experiments evaluated the effects of dietary Se and vitamin E on the ultrastructure of spermatozoa, ATP concentration of spermatozoa, and the effects of adding sodium selenite to semen extenders on subsequent sperm motility. The experiment was a 2 x 2 arrangement of treatments in a randomized complete block design. A total of 10 mature boars were fed from weaning to 18 mo of age diets fortified with two levels of supplemental Se (0 or .5 ppm) or vitamin E (0 or 220 IU/kg diet). The nonfortified diets contained .06 ppm Se and 4.4 IU vitamin E/kg. In Exp. 1, the spermatozoa from all boars were examined by electron microscopy. Vitamin E had no effect on structural abnormalities in the spermatozoa. When the low-Se diet was fed the acrosome or nuclei of the spermatozoa was unaffected, but the mitochondria in the tail midpiece were more oval with wider gaps between organelles. The plasma membrane connection to the tail midpiece was not tightly bound as when boars were fed Se. Immature spermatozoa with cytoplasmic droplets were more numerous when boars were fed the low-Se diet, but the occurrence of midpiece abnormalities occurred in boars fed diets with or without Se or vitamin E. Our results suggest that Se may enhance spermatozoa maturation in the epididymis and may reduce the number of sperm with cytoplasmic droplets. In Exp. 2, the concentration of ATP in the spermatozoa was evaluated in the semen of all treatment boars. When the low-Se diet was fed, ATP concentration was lower (P < .01), whereas vitamin E had no effect on ATP concentration. Experiment 3 investigated the effect of diluting boar semen with a semen extender with sodium selenite added at 0, .3, .6, or .9 ppm Se. Three ejaculates from each boar were used to evaluate these effects on sperm motility to 48 h after dilution. Sperm motility declined (P < .01) when Se was added to the extender, and this decline was exacerbated as the concentration of added Se increased (P < .01). The added Se was demonstrated to be tightly adhered to the spermatozoa. Overall, these results suggest that low Se-diets fed to boars resulted in abnormal spermatozoal mitochondria, a lower ATP concentration in the spermatozoa, and a loose apposition of the plasma membrane to the helical coil of the tail midpiece, but no effect from inadequate vitamin E was demonstrated. Adding sodium selenite to the semen extender reduced sperm cell motility.  相似文献   

10.
An investigation involving seven boars, active in artificial insemination, and 1,350 multiparous sows was conducted at a private farm and aimed at examining the relationship between sperm quality traits and boar fertility in terms of farrowing rate and litter size. This experiment was done for 6 months. The semen samples were evaluated for subjective sperm motility and concentration. Ejaculates with at least 1 × 108 sperm/mL and 70% sperm progressive motility were extended with a commercial medium to 30 × 106 sperm/mL and used for artificial insemination (AI). AI dose was 100 mL semen containing 3 × 109 spermatozoa. Aliquots of diluted semen were assessed for live morphologically normal spermatozoa (LMNS, eosin-nigrosin stain exclusion assay) and sperm chromatin instability (SCI, acridine orange assay). Farrowing rates according to different boar sperm varied (p < 0.001) from 59.3 to 88.92%. The mean values of LMNS (47.2~76.5%) and SCI (0.16~4.67%) differed significantly among boars. LMNS (r = 0.79, p < 0.05) and SCI (r = -0.90, p < 0.02) accounted for 62.2 and 81.7% of the variability in farrowing rates, respectively. After the combination of sperm traits, the relationship between percentage of LMNS with stable chromatin structure and farrowing rate was significant (r = 0.86, p < 0.05). The number of live piglets per parturition was not significantly correlated with sperm quality attributes. In conclusion, boar fertility after AI with freshly diluted semen can be predicted based on the evaluation of sperm morphology and chromatin integrity.  相似文献   

11.
Sperm handling, associated to artificial reproduction technologies (ART) such as in vitro fertilization (IVF) or the use of flow cytometry for cell analysis or sorting imposes volumetric extension of the sperm suspension and decreases sperm viability, presumably because of the removal of seminal plasma (SP) components. This study evaluated whether a 10% v/v of autologous SP (retrieved from the same donor boar) or homologous SP (e.g. from any of the four fertile boars included, other than the one providing the spermatozoa) would differently affect the viability of boar spermatozoa subjected to large extension in a simple saline medium [phosphate-buffered saline and 0.1% ethylenediaminetetraacetic acid (EDTA), PBSm] to a concentration of 0.3 x 10(6) spermatozoa/ml and incubated for 2 h at 30 degrees C. Sperm viability was monitored as membrane integrity [using the fluorophore carboxyfluorescein diacetate (C-FDA) and propidium iodide (PI)], mitochondrial function (using the fluorophore R-123) and motility characteristics [using Computer Assisted Sperm Analysis (CASA)]. Substraction of the SP and extension followed by incubation in PBSm significantly (p < 0.05) decreased sperm viability, which could be restored by addition of autologous SP. Furthermore, exposure of the extended spermatozoa to homologous SP (from any other individual boar) significantly (p < 0.05) varied with the source of the sire; some boars exerting beneficial effects (even surpassing the effects of the autologous SP; p < 0.05) while at least one boar negatively (p < 0.05) influencing the viability of the incubated spermatozoa. It is concluded that SP should be present when incubating highly extended spermatozoa. As a result of the obvious differences among boars, it would be advantageous to examine the ability of SP to maintain sperm viability prior to the use of SP pools during sperm handling in vitro.  相似文献   

12.
Epididymides from nine crossbred male pigs [Polish Landrace × (Duroc × Pietrain)] (n = 3 per each group) were used in this study to show whether there are any differences between androgen receptor (AR) distribution along epididymal duct of a GnRH agonist deslorelin-treated boars when compared to the control tissues. The active agent was administered by way of a subcutaneous controlled-release implant containing 4.7 mg deslorelin at 91 or 147 days of age respectively. Boars from two experimental groups and the control group were slaughtered at 175 day of age. Immunolocalization was performed using a polyclonal rabbit antiserum against the AR. In control boars, strong staining for AR was detected in nuclei of the epithelial (principal and basal) and stromal cells, whereas in boars treated with deslorelin the staining was confined to the principal cell nuclei. In those treated for 84 days, AR-immunostaining was weak or the principal cells were negative for the AR. Irrespective of the time from deslorelin insertion all stromal cells were immunonegative. The results demonstrate for the first time the effect of deslorelin on the distribution of the AR in the three regions of the boar epididymis. It is likely that stromal cells are more sensitive than epithelial cells to the regulation of AR expression by androgen. The morphological and functional alterations along the epididymal duct and lack of spermatozoa within the lumen after deslorelin treatment indicate that a potent GnRH agonist is likely responsible for an impairment of the microenvironment created by epididymal cells for sperm maturation and their storage.  相似文献   

13.
The aim of the study was to determine the relation between the semen quality, frequency of sperm defects, sperm dimensions and shape, and the ejaculate volume of Large White and Landrace boars. A total of 648 ejaculates collected from 31 Large White and 30 Landrace boars were divided into three groups according to the criterion of the ejaculate volume. In this study Landrace boars produced ejaculates with higher volume, sperm concentration, and total numbers of spermatozoa than Large White boars. Landrace boars also showed a lower frequency of sperm with morphological abnormalities (P < 0.05). Landrace boars sperm had larger heads, which were by 0.15 μm longer, and by a larger perimeter and area (P < 0.05). Landrace boar spermatozoa also had a longer flagellum and were generally larger and by 2.07 μm longer than Large White boar sperm (P < 0.05). Significant differences were also found in the shape of sperm of the two breeds (P < 0.05). Landrace boars sperm had more elongated heads, and the ratio of head size to flagellum length was lower than in Large White boars sperm (P < 0.05). Sperm from ejaculates with low volume had a shorter flagellum and a greater head length/flagellum length ratio than sperm from medium- and high-volume ejaculates (P < 0.05).  相似文献   

14.
In the period 1996–2006 two specific sperm defects, the knobbed acrosome (KA) defect and the immotile short‐tail sperm (ISTS) defect, showed a strong negative association with fertility in Finnish breeding boars. In this study, we examined the incidence of these two sperm defects in two pig breeds, their effects on fertility and their associations with sperm morphology and testicular histology. Semen samples from 2048 (1097 Yorkshire, 951 Landrace) boars were collected. None of the Landrace boars revealed either the KA defect or the ISTS defect. Of the Yorkshire boars, 0.8% were afflicted with the KA defect and 7.6% with the ISTS defect. Boars diagnosed with the ISTS defect produced no litters. Fertility data were available from two artificially inseminated (AI) boars and six farm breeding boars affected with the KA defect. Breeding boars with 45–81% knobbed spermatozoa (n = 6) did not produce any litters out of 71 sows bred. AI boars with 25–30% knobbed spermatozoa had a poor non‐return rate (on average 47% compared with 85% for normal control boars) and produced small litters, on average 2.5 piglets less than other boars of the same breed. Morphometry of testicular tissue and distribution of different cells in the seminiferous tubules were examined in nine boars. Boars with the KA defect had a smaller diameter of the seminiferous tubules (p < 0.05) and a lower number of Sertoli cells (p < 0.05) than controls. ISTS boars, in turn, had a significantly lower number of elongated spermatids (p < 0.05), and they also produced on average only 12% of the spermatozoa of normal boars. The ISTS defect is a manifestation of an autosomal recessive disease caused by an insertion in the KPL2 gene in porcine chromosome 16. Although we tried to map the KA defect, its aetiology remains unclear.  相似文献   

15.
In swine artificial insemination, several dose regimens are applied, ranging from 1.5 x 10(9) to 6.0 x 10(9) spermatozoa per intra-cervical insemination dose. A lower sperm dose is more profitable for artificial insemination centres and offers a more effective use of superior boars. To evaluate fertility, 50 boars were used for a total of 10 773 homospermic first inseminations at a dose of 2 billion spermatozoa. In addition, 96 boars were used at a dose of 3 billion spermatozoa for 34 789 homospermic first inseminations. Fertility was determined by a 60-day non-return rate (NR%) of first inseminations. Litter size was registered by total number of piglets born separately in primiparous and multiparous farrowings. On average, a sow was inseminated 1.5 times. A significant decrease was observed in all three fertility parameters (NR%, litter size of both primiparous and multiparous farrowings) with a dose of 2 billion spermatozoa compared with a dose of 3 billion spermatozoa. The NR% was 75.8% and 84.0% (p < 0.001), the mean litter size of primiparous farrowings 10.1 and 10.7 (p < 0.001) and the mean litter size of multiparous farrowings 11.7 and 12.1 (p < 0.001) for 2 and 3 billion spermatozoa/dose, respectively. The proportion of normal spermatozoa in the sperm morphology analysis correlated significantly with NR% in both insemination regimens: p < 0.001, r = 0.604 and p < 0.05, r = 0.223 for 2 and 3 billion spermatozoa/dose, respectively. These results confirm that quantity can at least partly compensate for poor sperm quality. When the boars with <70% normal spermatozoa in the morphology evaluation were excluded from the data there were no correlation between the sperm morphology and NR%. However, the difference between the NR% and litter size remained statistically significant (p < 0.001) in favour for the bigger insemination dose. In conclusion, a decrease in sperm dose from 3 to 2 billion spermatozoa on commercial farms will severely decrease prolificacy at least under field conditions, where a sow is inseminated an average of 1.5 times/heat, and the semen is typically used within 3 days after collection. We recommend that under commercial circumstances the homospermic semen doses contain no <3 billion spermatozoa/dose.  相似文献   

16.
2 insemination trials were conducted to assess the effect of different thawing diluents on deep frozen boar spermatozoa. The diluents used were boar seminal plasma, protein free seminal plasma, isotonic glucose solution, and OLEP (fructose, sodium pyruvate, CaC12, MgC12, KCL, NaC1, and NaHC03). The electrolyte levels and pH and osmotic pressure of the latter are similar to those of boar seminal plasma. 139 gilts were inseminated. The percentage of fertilized ova was similar for OLEP, protein free seminal plasma, and boar seminal plasma. However, thawing in isotonic glucose solution gave markedly poorer results. There were also differences in the fertility of spermatozoa from the different boars, though these were independent of the effects of the various thawing diluents. The possible effects of the thawing diluents are discussed. The need for methods of selecting boars with spermatozoa of good freezing quality is emphasized.  相似文献   

17.
Cryopreserved boar sperm is not used extensively for artificial insemination, owing to the poor fertility rates of the sperm after freezing and thawing. The sperm membrane is damaged as the cells are cooled from body temperature to 5°C (cold shock), as well as during the freeze–thaw process. Increasing the cholesterol content of boar sperm membranes could help them survive cryopreservation, similar to sperm from other species that are cold shock sensitive. The aim of this study was to determine the optimal cholesterol‐loaded cyclodextrin (CLC) concentration to use for boar sperm cryopreservation, and the influence of CLCs on the cryosurvival of sperm from boars classified as good or poor freezers. Treating boar sperm with 1 mg of CLC/120 × 106 sperm slightly improved (p < 0.05) the percentage of viable sperm after freezing–thawing. On the other hand, sperm, from both good and poor freezers, responded similarly to CLC treatment. Nevertheless, additional studies will be needed to study the effect of this treatment on other parameters of sperm quality.  相似文献   

18.
A porcine in vitro fertilization (IVF) system and seminal quality parameters of frozen–thawed boar semen were used to assess the effectiveness of two different thawing rates of frozen boar semen, and to address the question of whether differences between fertility of ejaculates could be predicted in a limited field trial. In the first experiment, two thawing procedures were analysed (37°C, 30 s; 50°C, 12 s) and no differences in sperm quality were found. However, when the procedure was 50°C, 12 s the IVF results showed a higher number of sperm per penetrated oocyte and a near 10 points higher rate of pronuclear formation. In the second experiment, the fertility results obtained in the limited field trial show to be efficient enough for application in a commercial use, especially for three of the employed boars (fertility ≥80%). In this limited study, the conventional seminal parameters are not accurate enough to discriminate good and bad boars in relation to fertility. On the contrary, parameters of in vitro penetrability are more precise to predict subsequent fertilities. As conclusion, the IVF fertilization system seems to be a good tool to evaluate the quality of frozen–thawed boar semen previous to its commercial way, to verify the bank semen storage quality and a good way to assay new sperm freezing procedures, as it is the more precise evaluating method in estimating the potential fertilizing ability.  相似文献   

19.
In this study, we tested the hypothesis whether the neutral Comet assay (NCA) and the Sperm‐Sus‐Halomax (SSH) test kit could provide similar measurements of post‐thaw DNA fragmentation of boar spermatozoa. Whole ejaculates or sperm‐rich fractions of boar semen were frozen in an extender containing lactose, lipoprotein fractions isolated from ostrich egg yolk (LPFo), glycerol (lactose‐LPFo‐G) or in a standard boar semen extender (K3), without the addition of cryoprotective substances. In all boars, both the NCA and SSH test showed similar levels of post‐thaw sperm DNA fragmentation in samples of the same ejaculates, regardless of the ejaculate collection procedure and extender. Yet, the levels of post‐thaw sperm DNA damage, detected by the NCA and SSH test, were more accentuated in spermatozoa frozen in the absence of cryoprotective substances. Both the NCA and SSH detected variations among individual boars in terms of post‐thaw sperm DNA fragmentation. Agreement between the measurements of the NCA and SSH was confirmed by scatter plots of differences, suggesting that the DNA integrity tests could detect the same sperm populations, which were susceptible to cryo‐induced DNA damage. The findings of this study indicate that the NCA and the SSH test are effective in detecting similar levels of sperm DNA fragmentation and reinforce their importance in the assessment of frozen‐thawed boar semen quality.  相似文献   

20.
The possibility of selecting boars for deep freezing of spermatozoa was evaluated by tests of frozen-thawed spermatozoa. 20 of 31 ejaculates were used for artificial insemination of 37 gilts. Boar seminal plasma and OLEP were used as thawing diluents. The thermoresistance test and the extracellular concentration of aspartate aminotransferase (ASAT) were used as indicators of fertility. Spermatozoa from 4 boars were utilized. 1 of the boars appeared to be of superior fertility, while the spermatozoa from another was infertile. The latter animal had been used for fresh artificial insemination trials, and had shown higher pregnancy rates than the average. Samples from this boar exhibited the lowest degree of motility after 3 hours storage at 37 degrees C, the greatest relative decrease of motility during the thermoresistance test, the greatest release of ASAT after thawing by OLEP, and greatest relative release of ASAT. These variations were statistically significant (p less than .05). The results show that there is a possibility of detecting boars with spermatozoa with potential low freezability.  相似文献   

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