They conducted a simple genetic test to identify the presence of the unusual form of the gene, the so-called M allele that other researchers had suspected might be correlated with out-of-season fertility, in their test flock and then validated the gene’s relationship with aseasonal breeding by observing that trait in the flock.
The finding, published in the August issue of the Journal of Animal Science (Vol. 87, No. 8), may be a boon for the sheep industry worldwide, especially when combined with the Sheep Program’s STAR system – a method to manage ewes to lamb five times in three years rather than once a year.
“The primary biological limit for sheep production worldwide is the seasonality of breeding, but the market for high-quality lamb is a 52-week thing,” said Doug Hogue, professor emeritus of animal science in the College of Agriculture and Life Sciences. His Cornell colleague Mike Thonney and former Cornell postdoctoral researcher Raluca Mateescu, now at Oklahoma State University co-authored the paper with Andrea Lunsford, a graduate student at OSU.
Although the presence of the M allele has been definitively correlated with the ability to breed out of season, the researchers caution that it may only be a marker for the gene actually responsible for the trait.
“Breeding out of season is a complex trait,” Mateescu said, “so there are a lot of genes controlling it.” Mateescu observed the phenotype – the physical expression of the gene – in the researchers’ flock during a postdoctoral fellowship at Cornell.
“In this case, we’re talking about a receptor gene for melatonin,” Thonney explained. Melatonin is a naturally produced hormone commonly found in many animals. The change in the DNA sequence of the M allele does not change the amino acid sequence of the protein. This means that it may be an accurate indicator for the phenotype of breeding out of season, though it’s uncertain whether the gene actually impacts how the sheep’s body reacts to melatonin. And there may be a risk of losing the association over generations, the researchers said, as recombination could occur between the marker and the functional gene.
Thus, the researchers stress that it will be very important to validate the gene’s ability to indicate for aseasonal breeding each time the allele is bred into a new sheep population.
“I think it’s very exciting … we only have one gene, but it’s definitely a tool that farmers can use,” said Mateescu, who is now focusing on placing markers across the sheep’s entire genome to more accurately determine which gene or genes directly affect the trait of aseasonal reproduction.
The allele is particularly useful for management under the STAR system, developed by Hogue and Cornell sheep farm manager Brian Magee in the early 1980s, which uses nutrition and conventional breeding techniques to reduce the time between heats. “If a ewe doesn't get pregnant when she is supposed to, instead of a year, it’s only 73 days [using the STAR system] until she has another opportunity,” Thonney said.
While the STAR system requires better nutrition and more farm labor to manage the lambing, each lambing event involves fewer ewes than traditional yearly lambing.
The researchers hope that the discovery of the M allele may help the STAR system adapt to consistently high levels of production without any additional risk to flock health.
The study was supported by the U.S. Department of Agriculture, Oklahoma Agricultural Experiment Station and New York Agricultural Experiment Station.
Blaine Friedlander | Newswise Science News
Plasma-zapping process could yield trans fat-free soybean oil product
02.12.2016 | Purdue University
New findings about the deformed wing virus, a major factor in honey bee colony mortality
11.11.2016 | Veterinärmedizinische Universität Wien
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine