Results 51 to 60 of about 726,910 (390)

Sperm death and dumping in Drosophila [PDF]

, 2004
Mating with more than one male is the norm for females of many species. In addition to generating competition between the ejaculates of different males, multiple mating may allow females to bias sperm use.
A Civetta, A Civetta, A Cordoba-Aguilar, AG Clark, AS Gilchrist, AS Gilchrist, B Jenzer, BI Arthur, CSP Price, D Scott, FM Hunter, GA Parker, GJ Lefevre, GT Miller, H Alonzo-Pimentel, HDM Moore, JK DeVries, L Xue, LG Harshman, LW Simmons, LW Simmons, M Otronen, MH Gromko, MH Gromko, MR Wheeler, S Pitnick, T Pizzari, TR Birkhead, WB Heed, WG Eberhard   +29 more
core   +1 more source

Sophisticated sperm allocation in male fowl [PDF]

, 2003
When a female is sexually promiscuous, the ejaculates of different males compete for the fertilization of her eggs; the more sperm a male inseminates into a female, the more likely he is to fertilize her eggs.
Pizzari, T., Cornwallis, C.K., Lovlie, H., Jakobssen, S., Birkhead, T.R.   +4 more
core   +1 more source

Re-sperm collection with a short abstinence time: a strategy for successful cryopreservation in cryptozoospermia [PDF]

Journal of Men's Health
Background: Recent studies suggest that short-term abstinence may improve semen parameters; however, its impact on cryptozoospermia remains underexplored.
Wen-Rui Zhao, Bo Liu, Xue-Feng Luo, Jin-Yan Xu, Chen Luo, Yuan Liu, Yang Xian, Fu-Ping Li   +7 more
doaj   +1 more source

Leydig cell metabolic disorder act as a new mechanism affecting for focal spermatogenesis in Klinefelter syndrome patients: a real world cross-sectional study base on the age

Frontiers in Endocrinology, 2023
BackgroundKlinefelter’s syndrome (KS) was once considered infertile due to congenital chromosomal abnormalities, but the presence of focal spermatozoa changed this.
Huang Liu, Zhenhui Zhang, Yong Gao, Hai Lin, Zhiyong Zhu, Houbin Zheng, Wenjing Ye, Zefang Luo, Zhaohui Qing, Xiaolan Xiao, Lei Hu, Yu Zhou, Xinzong Zhang   +12 more
doaj   +1 more source

Advances in Cryopreservation of Bull Sperm

Frontiers in Veterinary Science, 2019
Cryopreservation of semen and artificial insemination have an important, positive impact on cattle production, and product quality. Through the use of cryopreserved semen and artificial insemination, sperm from the best breeding bulls can be used to ...
M. R. Ugur, Amal Saber Abdelrahman, H. Evans, A. Gilmore, Mustafa Hitit, R. I. Arifiantini, B. Purwantara, A. Kaya, E. Memili   +8 more
semanticscholar   +1 more source

Effect of seven oriental herbs mixture (Jogyeongbohyeoldan) on the restoration of ovarian aging in aged mice

Clinical and Experimental Obstetrics & Gynecology, 2021
Purpose of Investigation: Ovarian aging remains a difficult problem in infertility treatment. The traditional oriental herbs have been widely used for female infertility treatment.
Jong-Kil Joo, Chae-Hak Lim, MinJung Park, HyeonJeong Kim, Chang-Woon Kim, Chul-Hee Yoon, Jeong-Eun Yoo, BoSun Joo   +7 more
doaj   +1 more source

DNA fragmentation index (DFI) as a measure of sperm quality and fertility in mice. [PDF]

, 2020
Although thousands of genetically modified mouse strains have been cryopreserved by sperm freezing, the likelihood of cryorecovery success cannot be accurately predicted using conventional sperm parameters.
Li, Ming-Wen, Lloyd, KC Kent
core   +1 more source

Sperm competition and sperm midpiece size: no consistent pattern in passerine birds [PDF]

, 2007
Sperm competition is thought to be a major force driving the evolution of sperm shape and function. However, previous studies investigating the relationship between the risk of sperm competition and sperm morphometry revealed inconclusive results and ...
Birkhead T.R, Katz D.F, McFarlane R.W, Retzius G   +3 more
core   +2 more sources

Of mice and sperm [PDF]

Proceedings of the National Academy of Sciences, 2006
When females are sexually promiscuous, the ejaculates of different males may compete for the fertilization of a set of ova, a process known as sperm competition. In internally fertilizing species, potential for sperm competition occurs whenever the ejaculates of different males cooccur in the female reproductive tract at the time of ovulation.
openaire   +3 more sources

Sperm morphology and sperm velocity in passerine birds [PDF]

Proceedings of the Royal Society B: Biological Sciences, 2008
Sperm velocity is one of the main determinants of the outcome of sperm competition. Since sperm vary considerably in their morphology between and within species, it seems likely that sperm morphology is associated with sperm velocity. Theory predicts that sperm velocity may be increased by enlarged midpiece (energetic component) or flagellum length ...
Lüpold S, Calhim S, Immler S, Birkhead TR   +3 more
openaire   +5 more sources