Spread your sperm the smart way
Attractive males release fewer sperm
per mating to maximise their chances of producing offspring across a range of females, according to a new paper on the evolution of ejaculation strategies. The findings by researchers at UCL (University College London) and the University of Oxford suggest that,...
The egg makes sure that sperm don't get too old
In contrast to women, men are fertile throughout life, but research at the Sahlgrenska Academy, University of Gothenburg, Sweden, has now shown that a fertilising sperm
can get help from the egg to rejuvenate. The result is an important step towards future stem cell therapy.
The risk of chromos...
CSHL scientists discover how 'companion' cells to sperm protect them from genetic damage
Cold Spring Harbor, N.Y. In plant pollen grains, sperm
cells, which carry the genetic material to be passed on to progeny, are cocooned within larger "companion" cells that are called pollen vegetative cells. These companions provide sperm
with energy and nourishment, and push them towards their...
Proteins in sperm unlock understanding of male infertility says new study
Proteins found in sperm
are central to understanding male infertility and could be used to determine new diagnostic methods and fertility treatments according to a paper published by the journal Molecular and Cellular Proteomics (MCP). The article demonstrates how proteomics, a relatively new fi...
Low sperm count may be associated with prenatal testosterone excess
Exposure to an excess of sexual steroids, like testosterone, during fetal development may be a potential risk factor for low sperm
count and motility, according to a new study accepted for publication in Endocrinology, a journal of The Endocrine Society.
"The majority of disorders affecting s...
Unique study shows oil, gas seismic work not affecting Gulf sperm whales
HOUSTON, Aug. 21, 2008 Noise can be irritating and possibly harmful for everything from mice to humans and maybe even 60-foot whales in the Gulf of Mexico.
In recent years, there has been concern that man-made noise may be a cause of stress for dolphins, whales and other marine mammals, bu...
Obese men have less semen, more sperm abnormalities, and should lose weight before trying for a baby
This release is available in Spanish . Obese men should consider losing weight if they want to have children, a scientist told the 24th annual conference of the European Society of Human Reproduction and Embryology today (Wednesday 9 July). Dr. A Ghiyath Shayeb, from the University of Aberd...
Diabetes linked to male infertility; excess sugars in the body have direct effect on sperm quality
This release is available in Spanish . Barcelona, Spain: Diabetes in men has a direct effect on fertility, a scientist told the 24th annual conference of the European Society of Human Reproduction and Embryology today (Wednesday 9 July). Dr. Con Mallidis from Queen's University, Belfast, U...
Normal-looking sperm may have serious damage; scientists urge more care in selection
This release is available in Spanish .
Barcelona, Spain: Intracytoplasmic sperm
injection (ICSI), where a single sperm
is injected into an egg to fertilise it, is increasingly used to help infertile men father children. Although the sperm
chosen for the procedure may appear quite normal, ...
Wiggle room: Cornell researcher borrows idea from sperm to provide energy for nanoscale robots
ITHACA, N.Y. In order to deliver medicine inside the human body, nanoscale medical devices need energy to carry out tasks, such as releasing drugs. Alex Travis, Cornell assistant professor of veterinary medicine, suggests creating a system that generates power for nanoscale robots, based upon how...
Mutant sperm guide clinicians to new diseases
Research published today in Nature Genetics shows that some rearrangements of the human genome occur more frequently than previously thought. The work is likely to lead to new identification of genes involved in disease and to improve diagnosis of genomic disease.
The scientists from the Wellco...
Primate sperm competition: speed matters
Researchers at UC San Diego and UC Irvine have found evidence that supports the theory that reproductive competition during the evolution of primate species has occurred at the level of sperm
cell motility. In a paper published online by the Journal of the Royal Society Interface, a team led by Mi...
The more promiscuous the female, the speedier the sperm
Female promiscuity appears to have triggered changes in the type of sperm
a male produces, according to new research on fish from central Africa.
The study, published in the Proceedings of the National Academy of Sciences of the USA, examines how competition for reproduction influences the sp...
Tracking sperm whales and jumbo squid
whale and its large prey, the jumbo squid, are among the deepest divers in the ocean, routinely reaching depths of 3,000 feet or more. Now, in a new study, a team of marine scientists reports the successful tagging of sperm
whales and jumbo squid swimming together off Mexico’s Pacific coa...
Early-stage sperm cells created from human bone marrow
Human bone marrow has been used to create early-stage sperm
cells for the first time, a scientific step forward that will help researchers understand more about how sperm
cells are created.
The research published today (Friday, April 13 2007), in the academic journal Reproduction: Gamete Biology...
Even when faint, ovary scent draws sperm cells
In this week's Analytical Chemistry, scientists at Indiana University Bloomington report biochemical machinery that allows mouse sperm
cells to follow the weakest of scents. Even when ovary extracts were diluted 100,000 times, some sperm
cells still found their mark.
A video demonstrating sperm
Study links high levels of nitric oxide to infertility and sperm DNA damage
Iranian scientists have linked a chemical that plays an essential role in many bodily functions to sperm
DNA damage and male infertility, the 22nd annual conference of the European Society of Human Reproduction heard today (Monday).
Dr Iraj Amiri, embryology laboratory director at the IVF Centre,...
Ecologists home in on how sperm whales find their prey
Ecologists have at last got a view of sperm
whales' behaviour during their long, deep dives, thanks to the use of recently developed electronic "dtags". According to new research published in the British Ecological Society's Journal of Animal Ecology, sperm
whales ?like bats ?use echolocation consi...
Chromosomal abnormalities in sperm higher after vasectomy reversal
Men who have had a vasectomy reversed have a very much greater rate of chromosomal abnormalities in their sperm
than do normal fertile men, a scientist told the 22nd annual conference of the European Society of Human Reproduction and Embryology in Prague, Czech Republic on Wednesday 21 June 2006. ...
How sperm crack the whip
Researchers have identified a key component of the mechanism spermatozoa use to abruptly convert their tail motion from a steady swimming undulation to the whip-cracking snap that thrusts them into an egg. The finding opens a new research pathway that the researchers said could help scientists both...
UK sperm donor crisis
A study by a leading UK fertility centre has found that the numbers of men ?especially students ?coming forward as potential sperm
donors fell sharply after 2000, almost certainly due to growing awareness that changes in the law would be removing the right to anonymity.
The fall in applications, ...
Human embryonic stem cells have the potential to develop into eggs and sperm in the laboratory
Scientists in the UK have proved that human embryonic stem cells can develop in the laboratory into the early forms of cells that eventually become eggs or sperm. Their work opens up the possibility that eggs and sperm
could be grown from stem cells and used for assisted reproduction, therapeutic c...
Protecting cells from their neighbors
.... In the first hours after fertilisation, the fate of its future development is determined. It is dictated by the separation of cells that will become sperm
and ovules - germ cells-, from the remaining cells, which will be responsible for forming the body organs and tissues -, and that comprise the somatic...
Sex in the Caribbean: Environmental change drives evolutionary change -- eventually
...ex. To clone a new colony requires immediately available energy, so when nutrients are scarce, it's better not to fragment. Nutrients to form eggs and sperm
needed for sex can, on the other hand, accumulate slowly over time.
O'Dea, with Jeremy Jackson, emeritus staff scientist at the Smithsonian and dir...
New research finds possible genetic link to cause of pregnancy loss and disorders
Further research revealed this is because aneuploidy was generated in the egg and passed on to the single-cell zygote that forms when a sperm
fertilizes an egg. And this led to the loss of the embryo.
"This work certainly points to Bub1 having a role in maternal age-induced fertility issu...
ICSI or IVF: Babies born from frozen embryos do just as well
...t running ICSI programme in the United States has found reassuring evidence that babies born from frozen embryos fertilised via ICSI (intracytoplasmic sperm
injection) do just as well as those born from frozen embryos fertilised via standard IVF treatment.
The researchers also compared babies born as a ...
Who goes abroad for fertility treatment and why?
...foreign patients into Belgium had stabilised at around 2100 patients per year, and that the majority of these were lesbian couples from France seeking sperm
There appeared to be a clear correlation between legal prohibitions in patients' home countries and the numbers who travelled abroad, he ...
Corals stay close to home
...an be encouraged.
A recent study by Australian biologist Jim Underwood has found surprisingly that despite the fact that corals cast their eggs and sperm
haphazardly into the oceans, certain species of coral show remarkable fidelity to their home range.
Underwood sampled DNA from coral reefs in the I...
Dolphins get a lift from delta wing technology
Using Computer tomography scanning of the fins of seven different species ranging from the slow swimming Amazon River dolphin and pygmy sperm
whale to the super-fast striped dolphin, the team made scaled models of the flippers of each species. Then they measured the lift and drag experienced...
Size did matter
... The mystery of giant sperm
present in some living animal groups today has tak...d fossilised evidence for reproduction using giant sperm
in a group of small aquatic crustaceans, called os...atozoa. Since modern ostracods still produce giant sperm
and manoeuvre them with the same organs as 100 mil...
Stress puts double whammy on reproductive system, fertility
...ones - glucocorticoids such as cortisol - that inhibit the body's main sex hormone, gonadotropin releasing hormone (GnRH), and subsequently suppresses sperm
count, ovulation and sexual activity.
The new research shows that stress also increases brain levels of a reproductive hormone named gonadotropin-i...
Not 1, but 2 kinds of males found in the invasive round goby
... and space."
The McMaster scientists compared the physical, hormonal and sperm
traits of hundreds of males, and found that the nest-guarding, parental mal...rrow heads. Both types of males produced sperm, but sneakers produced more sperm
than the parental males, and had bigger testes. By contrast, parental male...
Is this the beginning of the end of plant breeding?
...cies took a step closer to being realised with new research published in PLoS Biology this week.
The type of cell division that creates eggs and sperm
is called meiosis, and it differs from 'normal' cell division (mitosis) because instead of producing two genetically identical daughter cells, it prod...
Improving livestock productivity in Honduras
..., it directly assists milk and meat producers by determining the nutritional value of pastures, forages and potential cattle feeds; by reinforcing the sperm
bank and selection criteria for cattle for higher meat and milk production; and by improving diagnosis of diseases affecting livestock. Secondly, the ...
Yeast missing sex genes undergo unexpected sexual reproduction
...or fusion products may be aneuploid, with chromosomes from mother and father not paired exactly one to one, but the great majority of those fusions of sperm
and egg don't make it to the implantation and pregnancy stage," Reedy said. "That's why it is important to find models like this, so that we may shed ...
The evolutionary foundation of genomic imprinting in lower vertebrates
...esults showed that, as mammalian Igf2 CpG island, goldfish Igf2 CpG island was a parental differentially methylated region that was hypermethylated in sperm
but unmethylated in eggs. The authors also indicated that, unlike mammalian imprinting gene DMR, the unmethylated DMR of maternal allele could ...
Genital stimulation opens door for cryptic female choice in tsetse flies
...ite of changes in female reproduction, including reduced ovulation, reduced sperm
storage and increased re-mating attempts by the females. "To the best of ou...Costa Rica.
Cryptic female choicethe ability of females to control which sperm
reaches their eggs during and after the mating processleads to rapid evolut...
Mothers give interloper's offspring a head start in life
"Because females can often store sperm
for several weeks, they may typically only copulat...er laid eggs."
Even if females obtain a mix of sperm
before laying, it is possible that the sperm
from extra-pair males is more successful in fertil...
Can happiness be inherited?
...the time of their conception.
Brain chemicals such as endorphins, and drugs, such as marijuana and heroin are known to have significant effects on sperm
and eggs, altering the patterns of genes that are active in them.
"It is well known, of course, that parental behavior affects children, and that th...
Drugs needed to preserve eggs for reproduction need to be given in stages
... where it appears to afford additional protection. Dr. Eroglu has given mice eggs that added protection by injecting sugar in a process similar to how sperm
can be injected for fertilization. He's found it dramatically reduces the temperature needed to reach the glasslike preserved state. In fact, he's sho...