Showing posts with label Genetics. Show all posts
Appetite Genes Are Key To Better Poultry Diets
The welfare
of poultry could be improved by a discovery about how chickens regulate
their appetites. Scientists have identified how a chicken's genetic
make-up can affect the signals sent from its stomach to its brain that
tell a chicken when it has had enough to eat.
Poultry farmers
often have to restrict food for chickens because some birds are
insensitive to feelings of fullness and can overeat, affecting their
ability to reproduce.
The study could make it easier to develop methods to develop diets that reduce excess growth more naturally in these birds.
Researchers say
that genetic differences, which affect when chickens recognise when
they have had enough to eat, could date back thousands of years when
chickens were first domesticated and breeds were selected for their
size.
The research
was carried out by The Roslin Institute at the University of Edinburgh.
Dr Ian Dunn, who led the study, said: "The findings shed greater light
on food intake in birds and help us understand why some breeds - in
general the faster growing types of chickens - are more insensitive to
feelings of fullness than others."
The study,
published in the American Journal of Physiology, Endocrinology and
Metabolism, focused on a protein called cholecystokinin (CCK) that has a
key role in sending signals linked to being full from the gut to the
brain.
The
researchers, funded by the Biotechnology and Biological Sciences
Research Council, found that some birds were better equipped than others
at recognising the protein, making them more effective in triggering
signals of feeling full.
The study
involved cross-breeding a fast-growing meat production strain of chicken
with a relatively slow-growing, chicken. The researchers looked at how
the protein was processed in both types of chickens and in the new cross
breed.
They showed that reduced levels of protein that recognises the fullness signal also affected the chicken's natural body weight.
Their findings
back up the theory that, when poultry were domesticated thousands of
years ago and bred for increased size, their appetite levels were
changed. The study could also help inform research looking at appetite
regulation in other animals.
Dr Dunn said:
"All species regulate their appetites to make sure the amount of food
taken in is just the right to maintain body weight and fat content. Our
research has shown that there is genetic variation in the interpretation
of biological signals sent relating to being full. This also affects
what would be considered to be the natural body weight of chickens."
World Poultry
Oregon University Unveil New Dark Tomato
Oregon
State University has unveiled a new tomato - the "Indigo Rose." It’s a
dark purple tomato grown using natural genetics, rather than lab
engineering. The university has been carrying out projects aiming at the
production of dark tomatoes in recent years, as they are known to
contain high levels of antioxidants.
There
is not yet proof that the variety will be more healthy, but it is
certainly striking in appearance. Jim Myers, professor of vegetable
breeding said, "It is really a different tomato. The colour – and not
only the fruit is dark purple, but the foliage will be much more purple.
On top of that, it's just a really nice-eating tomato."
Myers
says the tomato's unusual look means growers should be careful not to
pick it too early. He says it grows to the size of a golf ball, and will
lose a little of its shine, when it's ready to pick.
At least four seed companies are known to be selling the product already.
Source: news.opb.org
Thoroughbred Race Horses All Traced to One 17th-Century Mare
Posted by Unknown in Genetics, Horse and Equine, Research and Studies, UK
(ABC News)
All the great names in thoroughbred horse racing — from Secretariat to
Man O’War, from Seabiscuit to Seattle Slew — they’re all related, and a
team of geneticists has now traced their talent for speed back to a
single ancestor. The “speed gene” that made them all so fast was
apparently a genetic aberration, and it probably started with one
British mare who lived in the mid-17th century.
Emmeline
Hill of University College Dublin led a team that analyzed DNA in 593
horses from 22 modern breeds, as well as museum specimens from 12
historically famous stallions. Modern genetics have become sophisticated
enough that they could tell, with considerable precision, what the
horses had in common.
“The
results show that the ‘speed gene’ entered the thoroughbred from a
single founder, which was most likely a British mare about 300 years ago
when local British horse types were the pre-eminent racing horses,
prior to the formal foundation of the thoroughbred racehorse,” said Hill
in a prepared statement.
She and her colleagues published their findings in the journal Nature Communications.
Lest
this seem like some arcane animal study, it does involve a big-money
sport and, more important, questions about how genetic characteristics
can be inherited and traced. If you can decipher the genes that make
thoroughbreds so fast, say the researchers, you can also find clues to
genetic diseases in people. Thoroughbred horses are useful for study
because the records of their ancestry are — forgive the pun — really,
really thorough, going back centuries.
The
great speed horses all shared two genes associated with muscle
development. The combination did not show up in regular farm horses, or
donkeys, or zebras.
Horses
with the two genes were consistently top sprinters. It’s no accident
that the Kentucky Derby is a mile and a quarter, usually won in just
more than two minutes. Other genetic combinations were found in horses
that were slower but able to run longer.
Place your bets.
Researchers Aim to Flick The High-Carbon Switch on Rice
Posted by Unknown in Genetics, Research and Studies, Rice on Monday, 28 January 2013
'C4 photosynthesis', as used by maize and sorghum, could greatly boost rice yields, after a decade of slowing improvements.
Codename: C4
rice project. Mission: to modify photosynthesis in rice to boost crop
yields. Duration: 15 to 25 years. This might sound like science fiction,
but it is already under way at the International Rice Research
Institute (IRRI) in
the Philippines, where William Paul Quick and his team have been working
since 2008 on changing the photosynthesis process in rice from the C3
carbon-fixation mechanism, common to 98% of all plants, to its much more
efficient C4 counterpart.
Some 50
species, including maize and sorghum, have completed this step
naturally, enabling the plants to devote most of their energy to
carbon-fixing, and thus to growth. "At present we are studying how far
the cell structures and enzymes required to achieve C4-type
photosynthesis are already present in rice and closely related plants,"
says Nourollah Ahmadi, a rice specialist at France's Centre for International Co-operation on Farming Research for Development. "The
aim is to activate the available but as yet inactive cell structures
and enzymes and to introduce the ones that are lacking by genetic
transformation, drawing on other plants."
This could
increase output by as much as 50%, bringing about another green
revolution, capable of responding to the foreseeable demand for food in
2050, when there will be 9 billion mouths to feed. Rice is currently the
staple foodstuff for more half the world's population, with more than 1
billion people depending on rice farming for their livelihoods. "For
every additional billion people, an extra 100m tonnes of rice will need
to be produced," says Ahmadi. In contrast, the annual increase in yields
has slowed since the 1990s, from 2% to just 1%.
Research into
rice now concentrates on creating varieties that are more productive and
more resistant to the various forms of stress, caused by disease (such
as pyriculiariosis) or environmental factors (flooding, drought, extreme
temperatures and high salt concentrations).
"Rice will be
one of the cereals most affected by climate change," says Robert
Zeigler, the head of IRRI. "So it's vital to prepare production systems
and rice growers for change if we want to maintain a certain dynamic."
Hopes are consequently high for the programme launched by IRRI and China
to sequence the genome of 10,000 of the 120,000 known rice varieties.
The first results are due in June.
"Thanks to new
sequencing techniques, we can determine the specific features of the
genome of any particular variety," says Mathieu Lorieux, a geneticist at
France's Development Research Institute (IRD). "Our work then consists
in cross-breeding the most useful species to obtain new ones that meet
consumer demands and environmental constraints, and are resistant to
disease."
Lorieux is
taking part in a programme to overcome the sterility barrier between
Asian (Oryza sativa) and African rice (Oryza glaberrima), the idea being
to develop hybrid varieties combining the former's productivity with
the robustness of the latter. He is also working on the plant's
architecture, so that each shoot produces more grain.
In 2011 IRRI launched a four-year programme on the Mekong delta, in Vietnam, to add flood and salt-tolerant genes to rice.
"More or less
all over the world, the potential yield from rice is about 10 tonnes a
hectare, whereas the global average is only 4.5 tonnes," Ahmadi
explains. "But the effort required to bridge this gap is increasing all
the time."
No transgenic
rice varieties are currently being cultivated, but "golden rice", a
variety developed a decade ago to have added vitamin-A, did cause
controversy. Lorieux is certain we shall one day eat transgenic rice:
"If a new disease appears and there are no resistant rice varieties, we
shall have to look for a resistant gene elsewhere or maybe make a
synthetic gene ... or give up growing rice."
This article originally appeared in Le MondeGilles van KoteGuardian Weekly
Scientists Make Silkworms 'Spin Spider webs'
Scientists have genetically engineered silkworms to make artificial spider silk.
It
is hoped the breakthrough could lead to the development of stronger
fibres for textiles, bandages for burn victims and bullet-proof vests.
The
GM silkworms spin tough fibres containing spider silk proteins that are
more elastic and extensible, making it more suitable for use in a range
of medical applications.
Territorialism and cannibalism among spiders pose challenges to spider farming as a viable means of manufacturing silk.
Dr
Donald Jarvis, of the University of Wyoming in the United States, and
colleagues created transgenic silkworms expressing spider gene
sequences.
Spider
silk proteins have been long produced in transgenic bacterial, yeast,
plant, insect and mammalian cells. However, previous attempts to
incorporate them into fibres spun by silkworms led to relatively low
yields.
But
the new technique, reported in Proceedings of the National Academy of
Sciences, led to fibres at least as tough as spider silk and stronger
than those spun by silkworms.
So silkworms may be used as factories for manufacturing tough silk fibres containing spider silk proteins, said the researchers.
Dr
Jarvis said: "Spider silks have enormous potential as biomaterials for
various applications, but serious obstacles to spider farming preclude
the natural manufacturing approach.
"Thus, there is a need to develop an effective biotechnological approach for spider silk fibre production.
"In
addition to being used as sutures, silk fibres hold great potential as
biomaterials for wound dressings, artificial ligaments, tendons, tissue
scaffolds, microcapsules, and other applications.
"Silkworms
are the current biological source of silk sutures, but spider silk
fibres have superior mechanical properties that are ideal for procedures
requiring finer sutures, such as ocular, neurological, and cosmetic
surgeries.
Pigeon Pea Genome Cracked: Benefits Farming Millions in Asia & Africa
Posted by Unknown in Africa, Biotechnology, Genetics, Hunger and Famine, India, Pigeon Pea, Research and Technology, Research Institute
A
team of scientists has claimed to have achieved a major breakthrough by
successfully sequencing the genome of Pigeon pea, considered an “orphan
crop” and “poor peoples’ meat “ for its protein-rich content, mainly
grown by small and marginal farmers across the world.
(ZEM Science)
Years of genome analysis by a global research partnership led by the
Hyderabad-based International Crops Research Institute for the Semi-Arid
Tropics (ICRISAT) has resulted in the identification of 48,680 pigeon
pea genes.
In
the fight against poverty and hunger amid the threat of climate change,
highly nutritious, drought-tolerant crops are the best bets for small
farmers in marginal environments to survive and improve their
livelihoods and now the pigeon pea gives the hope with its genome fully
sequenced.
Pigeon
pea, grown on about 5 million hectares in Asia, sub-Saharan Africa and
South-Central America, is a very important food legume for millions of
the poor in the semi-arid regions of the world.
Unfortunately,
its productivity is less than one ton though it is considered as the
“poor people’s meat” because of its high protein content.
Pigeon
pea is the first “orphan crop”, the first “non-industrial crop” and the
second food legume (after soybean) with a completed genome sequence.
The
scientific partners include the International Initiative for Pigeon pea
Genomics (IIPG), led by ICRISAT, BGI – Shenzhen (China), USresearch
laboratories like University of Georgia, University of California-Davis,
Cold Spring Harbor Laboratory, and National Centre for Genome
Resources, and support from the CGIAR Generation Challenge Programme
based in Mexico.
The
journal Nature Biotechnology had recently featured this development
besides giving clues on how the genomics sequence could help improve the
crop for sustainable food production, particularly in the marginal
environment ofAsia and Sub-Saharan Africa.
“
A couple of hundreds of these genes were found unique to the crop in
terms of drought tolerance, an important trait that can be transferred
to other similar crops like soybean, cowpea or common bean that belong
to the same family, “ the journal said.
“The
mapping of the pigeon pea genome is a breakthrough that could not have
come at a better time. Now that the world is faced with hunger and
famine particularly in the Horn of Africa brought about by the worst
drought of the decades, science-based, sustainable agricultural
development solutions are vital in extricating vulnerable dry land
communities out of poverty and hunger for good,” says ICRISAT Director
General William D. Dar.
“The
sequence will significantly speed up and reduce the cost of screening
the ‘good genes’ within the stored pigeon pea seed collections in gene
banks like that of ICRISAT, dramatically reducing the cost of developing
new improved varieties for farmers. Now we can breed a new variety in
just 3 years as against 6-10 years before, “claims Rajeev Varshney, lead
scientist and project coordinator.
Prof.
Huanming Yang, Chairman, BGI-Shenzhen, the world’s largest genomics
institute and a key partner of this project said he was confident of
forging more dynamic and fruitful partnerships between Indian and
Chinese genomic scientists.
Significantly,
it is for the first time that the Consultative Group on
International Agricultural Research (CGIAR) had supported the
India-based center like ICRISAT for leading the genome sequencing of a
food crop.
