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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.


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Journal ArticleDOI
TL;DR: This is the first report estimating the percentage of HPV-positive sperm in infected subjects and the association between HPV infection and sperm motility.

123 citations

Journal ArticleDOI
TL;DR: Scalingup of the experimental insemination procedure yielded better fertilization rates while conserving the individual differences due to the breeder pairs, and the fertility of seabass sperm decreased exponentially after 10 s following sperm activation and was zero by 1 min.
Abstract: Seabass Dicentrarchus labrax sperm concentration was high (up to 60 × 109 spz ml−1) but decreased significantly at the end of the reproductive season (mid-March) in monthly sampled fish The spermiation period may be shortened by frequent stripping Sperm can be prediluted up to 1: 128 in non-activating medium without loss of initial motility and motility duration Immediately after activation by transfer to sea water, all the spermatozoa were motile for 10 s and then the number of motile cells decreased progressively but sharply to zero, so that the duration of sperm motility was very short (40 s) As a consequence, the fertility of seabass sperm decreased exponentially after 10 s following sperm activation and was zero by 1 min The sperm requirements for optimal fertilization were c 66 000 spermatozoa per egg Scalingup of the experimental insemination procedure yielded better fertilization rates while conserving the individual differences due to the breeder pairs

123 citations

Journal ArticleDOI
01 Oct 2010-Genetics
TL;DR: It was found that while sperm accumulation into storage was unaffected, sperm depletion from storage sites was significantly decreased (or impaired) in the absence of SP, indicating a direct role for SP in the release of sperm from storage.
Abstract: The Drosophila seminal fluid protein (SFP) sex peptide (SP) elicits numerous post-mating responses, including increased egg laying and decreased sexual receptivity, in the mated female. Unlike other SFPs, which are detectable in mated females for only a few hours post mating, SP is maintained—and its effects are sustained—for several days. The persistence of SP in the mated female's reproductive tract is thought to be a consequence of its binding to, and gradual release from, sperm in storage, which maintains SP's ability to act within the female reproductive tract. Recent studies have shown that several other SFPs, acting in a network, are needed for SP's localization to sperm and are necessary for the efficient release of sperm from storage. This result suggested an additional new role for SP modulating the release of sperm from storage. We tested for this possibility by examining sperm storage parameters in mated females that did not receive SP. We found that while sperm accumulation into storage was unaffected, sperm depletion from storage sites was significantly decreased (or impaired) in the absence of SP. Mates of males expressing a modified SP that is unable to be released from sperm showed a similar phenotype, indicating that release of sperm-bound SP is a necessary component of normal sperm depletion. Additionally, SP null males were more successful in a sperm competitive environment when they were first to mate, which is likely a consequence of higher retention of their sperm due to defective sperm release. Our findings illustrate a direct role for SP in the release of sperm from storage.

122 citations

Journal ArticleDOI
TL;DR: The relationship of seminal white blood cells and sperm function is evaluated, as reflected in the zona-free hamster egg penetration assay, and the possible mode of action of the white cells are investigated.
Abstract: The presence of white blood cells in semen has been associated with male infertility. Previous studies indicate that pyospermia occurs in conjunction with decreases in sperm motility, number of normal sperm forms, and penetration rates in the zona-free hamster egg sperm penetration assay. We have evaluated the relationship of seminal white blood cells and sperm function, as reflected in the zona-free hamster egg penetration assay, and have investigated the possible mode of action of the white cells. Egg penetration rates decreased when white blood cells from fertile or potentially fertile donors were added to their sperm suspensions prior to preincubation and at insemination in the in vitro assay. Zona-free hamster egg penetration assay results were also inhibited when the supernatant from white blood cells incubated in Biggers, Whitten, and Whittingham (BWW) medium overnight were introduced to sperm-oocyte suspensions at insemination. Conversely, egg penetration rates were enhanced in samples from hypofertile individuals when white blood cell concentrations in the semen or WBC/sperm ratios were reduced, either by physical removal or as a result of antibiotic therapy. The physical presence of leukocytes, and possibly, the extracellular release of lysosomal enzymes may be responsible for the inhibitory effects in vitro. Although the mechanism(s) by which white blood cells interfere with the fertilizing capacity of spermatozoa are not clear, it is quite obvious that their presence in the in vitro environment is undesirable and can mask an individual's actual fertilizing potential.

122 citations

Journal ArticleDOI
TL;DR: Age and genetic group affected the characteristics of the scrotum, testes, and TVC, sperm production and semen quality in bulls and could be assessed for breeding soundness evaluation.

122 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20241
2023973
20222,093
2021538
2020530
2019498