Semen

About: Semen is a research topic. Over the lifetime, 14571 publications have been published within this topic receiving 407739 citations. The topic is also known as: come & ejaculate.

Results of 55 intracytoplasmic sperm injection cycles in the treatment of male-immunological infertility.

Abstract: Antisperm antibodies present in the semen can be a primary cause of infertility. If the proportion of spermatozoa carrying antisperm antibodies is very high, then usually a poor result ensues in standard in-vitro fertilization. We therefore employed intracytoplasmic sperm injection (ICSI) in 55 cycles (37 patients) where the proportion of antisperm antibody-bound spermatozoa was 80% or higher, as determined by the mixed antiglobulin reaction (MAR) test. The type and location of antisperm antibodies were determined by the immunobead test in 30 of the 37 patients. The mean normal fertilization rate was 75.7% in these 55 cycles, which was significantly higher than the fertilization rate in another 1767 ICSI cycles (69.2%) performed over the same period and where MAR-negative semen (the level of antisperm antibodies was < 80%) was used for microinjection. Embryonic development was comparable, but a higher proportion of poor-quality embryos was obtained with MAR-positive than with MAR-negative semen samples. Out of the 55 patients, 53 had embryos replaced (96.4%) and a fetal sac was detected by ultrasonography in 14 patients (26.4%). The data indicate that fertilization, embryo development and pregnancy rates after ICSI are not influenced significantly by the proportion of antisperm antibody-bound spermatozoa, nor by the dominant type of antibodies present, nor by the location of the antisperm antibody on the spermatozoa. The conclusion of this study is that ICSI should be the primary choice for patients who have high numbers of antisperm antibodies present in their semen.

Effect of sperm DNA damage and sperm protamine deficiency on fertilization and embryo development post-ICSI.

Abstract: The aim of this study was to evaluate the effect of sperm DNA damage and protamine deficiency on fertilization and embryo development post-intracytoplasmic sperm injection (ICSI), and also to assess the effect of protamine deficiency on DNA damage. Semen samples were collected from 28 patients participating in the ICSI programme. Following sperm preparation and ICSI, the remaining processed semen samples were used to assess protamine deficiency and DNA damage employing chromomycin A3 (CMA3) staining and comet assay, respectively. Comet parameters, CMA3 percentage positivity, fertilization rate, embryo cleavage score and embryo quality score were assessed. Except for CMA3, none of the comet parameters showed significant correlation with fertilization rate. However, among comet parameters, head area and head intensity showed positive correlation with the embryo cleavage score, while comet mean intensity and head mean intensity showed a significant negative correlation with CMA3 positivity. Results of this study demonstrate that DNA fragmentation is more frequent in protamine-deficient spermatozoa. Unlike protamine deficiency, sperm DNA fragmentation does not preclude fertilization. Nonetheless, embryos derived from spermatozoa with high DNA damage have a lower potential to reach blastocyst stage.

Effect of dietary fat on the fatty acid composition and fertilizing ability of fowl semen.

Abstract: Broiler breeder roosters received two diets, containing either 5% salmon oil (SO) or 5% corn oil (CO). The diets differed essentially in their polyunsaturated fatty acid (PUFA) composition, with n-6:n-3 fatty acid ratios of 41.6 in SO and 1.5 in CO. The effects of these diets on the fatty acid composition of spermatozoa and seminal plasma, and on fertility evaluated after artificial insemination were observed. Whatever the diet, the fatty acid composition of spermatozoa showed notable amounts of 20:4n-6 (5-9%) and 22:4n-6 (15-21%). These essential fatty acids were not detected in the diets and were synthesized from 18:2n-6, which was abundant in the diet (15-16%) but low in spermatozoa (2-3%). Spermatozoa were also very rich in saturated fatty acids (39%). There was a clear influence of dietary lipids on the spermatozoa fatty acid profile: the proportion of n-3 fatty acids in spermatozoa from males fed SO compared to CO was higher (9.6% vs. 4.3%) and that of n-6 fatty acids was lower (22.4% vs. 33.3%). The fatty acid composition of seminal plasma included a higher proportion of saturated fatty acids (49%) than the proportion in spermatozoa, whereas minor fatty acids (14:0, 16:1n-7, 16:1n-9, 22:5n-3) were not detected. The influence of dietary lipids on the seminal plasma fatty acid profile was the same as for the spermatozoa, especially in the PUFA profile. In addition, the SO diet gave significantly higher fertility rates (96%) than the CO diet (91.6%). These results clearly show that the lipid composition of the diet may modify the fatty acid composition of the semen and its fertilizing ability.

Puberty in beef bulls: acrosome morphology and semen quality in bulls of different breeds.

Abstract: Semen characteristics were evaluated every 2 wk from 7 through 13 mo of age in 31 beef bulls representing six breed groups (Hereford, Angus, Hereford x Angus crossbreeds, Angus x Hereford crossbreds, Red Poll and Brown Swiss). Breeds differed in age at puberty, defined as the age at which an ejaculate was first obtained that contained a minimum of 50 x 10(6) total spermatozoa with at least 10% progressive motility (Hereford, 326 +/- 9 d; Angus, 295 +/- 4 d; Hereford x Angus, 300 +/- 8 d; Angus x Hereford, 296 +/- 9 d; Red Poll, 283 +/- 9 d and Brown Swiss, 264 +/- 9 d). Significant breed differences also were observed in concentration of spermatozoa, progressive motility, seminal protein concentration, abnormal spermatozoa and acrosomal morphology. Considerable variation was observed for the majority of pubertal traits among the 31 bulls, indicating that differences in stage of pubertal development existed among and within breeds of beef bulls between 7 and 13 mo of age. However, adjustment of data to age at puberty negated breed differences (P greater than .10), indicating that the pubertal patterns of change occurring in each semen characteristic were similar for the breeds evaluated. Concentration of spermatozoa, progressive motility, seminal protein concentration, percentage spermatozoa with normal head and tail morphology and percentage spermatozoa with normal acrosomal morphology increased (P less than .01) from puberty through 16 wk after puberty in all bulls and all breds. During the first 6 wk after puberty, rapid increases (P less than .01) were observed in percentage spermatozoa exhibiting normal head morphology (excluding acrosomes) and progressive motility, and a rapid decrease (P less than .01) was observed in percentage spermatozoa with proximal cytoplasmic droplets, with values at +6 wk approaching those reported for mature bulls. Percentage spermatozoa with normal acrosomal morphology and concentration of spermatozoa improved more slowly and had not reached mature levels by 16 wk after puberty. Because age at puberty varied by 62 d among breeds and 88 d among bulls and important characteristics of semen quality improved slowly after puberty, careful evaluation of the stage of pubertal development in individual bulls is recommended before selecting young bulls for natural breeding or artificial insemination. Additional investigations are needed to define the patterns of pubertal development through sexual maturity in beef bulls and to establish relationships to fertility.

Characterization of a fucose-binding protein from bull sperm and seminal plasma that may be responsible for formation of the oviductal sperm reservoir

Abstract: Oviductal sperm reservoirs have been found in cattle, mice, hamsters, pigs, and horses. In cattle (Bos taurus), the reservoir is evidently formed when sperm bind to fucosylated ligands resembling Le(a) trisaccharide on the surface of oviductal epithelium. The aim of this study was to characterize the fucose-binding protein on bull sperm. Fresh ejaculated sperm were extracted with 0.5 M KCl in Hepes-balanced salts. Extracts were subjected to affinity chromatography using immobilized Le(a) trisaccharide (alpha-L-Fuc[1,4]-beta-D-Gal[1,3]-D-GlcNAc). Two-dimensional PAGE of the affinity chromatography eluates revealed a prominent protein of approximately 16.5 kDa and a pI of 5.8. This protein inhibited binding of sperm to oviductal explants. A similar analysis of proteins extracted from capacitated sperm (which do not bind to oviductal epithelium) showed a reduction in the amount of the 16.5-kDa protein. When examined by epifluorescence microscopy, live uncapacitated sperm labeled over the acrosome with a fucose-BSA-fluorescein isothiocyanate (FITC) conjugate, while capacitated sperm did not. When capacitated sperm were treated with 16.5-kDa protein, labeling with fucose-BSA-FITC was partially restored. The comparative ease with which the protein was removed from sperm and its apparent reassociation with sperm suggested that it could be a peripheral protein derived from epididymal or accessory gland fluids. Blots of SDS-PAGE gels of seminal plasma proteins revealed the presence of a Le(a)-binding protein with an apparent mass of 16.5 kDA: Amino acid sequencing of two tryptic fragments of the protein purified from sperm extracts identified it as PDC-109 (BSP-A1/A2), a product of the seminal vesicles.