Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
..
. Farming News .




FARM NEWS
Important mutation discovered in dairy cattle
by Janne Hansen for Aarhus News
Aarhus, Denmark (SPX) Jan 06, 2014


"Our study demonstrates that embryonic lethal mutations account for a non-negligible fraction of the decline in fertility of domestic cattle and that associated positive effects on milk yield may account for part of the negative genetic correlation. This is at least the seventh example in livestock of an allele that is deleterious in the homozygous state being maintained at high frequency in the populations because of the selective advantage it confers to heterozygotes."

Scientists have found a genomic deletion that affects fertility and milk yield in dairy cattle at the same time. The discovery can help explain a dilemma in dairy cattle breeding: the negative correlation between fertility and milk production.

For the past many years milk yield in Scandinavian dairy cattle has gone in one clear direction: up. This has been due to targeted breeding programmes and modern breeding methods. Despite putting large weight in the breeding goal in Nordic countries, almost no improvement is achieved for fertility.

It now seems that this unfavourable correlation between milk yield and fertility is partially affected by a deletion of a simple gene sequence. The presence and effects of this mutation have recently been discovered by scientists from Aarhus University, University of Liege, MTT Agrifood Research Finland, in collaboration with the Danish Agricultural Advisory Service and the Nordic Cattle Genetic Evaluation.

Scientists, farmers and advisors have generally assumed that the reduction in fertility is primarily due to the negative energy balance of high-producing cows at the peak of their lactation but now the scientists have also found a genetic explanation.

"We have discovered a deletion encompassing four genes as the causative variant and shown that the deletion is a recessive embryonically lethal mutation, explains Goutam Sahana. This means that the calves die while they are still embryos and are aborted or reported as insemination failure.

The fact that the mutation is recessive means that both parents must carry it and pass the genes on to their calf for the calf to be affected. The bulls carrying the deletion can be routinely identified in on-going genomic selection program and by avoiding carrier-by-carrier matings a quantum jump in fertility could be achieved in Nordic red breeds, adds Goutam Sahana.

Can't have your cake and eat it too
To make matters worse, this particular mutation has become rather common in Nordic Red cattle, however, the deletion is totally absent in Nordic Holstein and Danish Jersey populations. Based on the frequency of the mutation in the population, it is estimated that 2.89, 1.32 and 0.42% of embryos are dying in Finnish Ayshire, Swedish Red and Danish Red cattle respectively due to this mutation.

The reason that the deleted gene sequence causing embryo mortality has become relatively widespread is that it has such as strong positive effect on milk yield. By selecting for high milk yields, breeders have inadvertently also selected for embryo mortality - a situation of so-called hitchhiking.

"Our study demonstrates that embryonic lethal mutations account for a non-negligible fraction of the decline in fertility of domestic cattle and that associated positive effects on milk yield may account for part of the negative genetic correlation. This is at least the seventh example in livestock of an allele that is deleterious in the homozygous state being maintained at high frequency in the populations because of the selective advantage it confers to heterozygotes."

Read the scientific article in PloS Genetics here.

.


Related Links
Aarhus University
Farming Today - Suppliers and Technology






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





UAV Payloads 2014, 24 - 25 June - London, UK
FARM NEWS
Hong Kong arrests 64 for smuggling baby formula
Hong Kong (AFP) Jan 03, 2014
Hong Kong customs officials said Friday they had arrested 64 people for unlicensed baby milk powder exports, in a move aimed to stifle the smuggling of formula before Chinese New Year. The ongoing operation, which started Thursday, has already netted 64 people who attempted to bring a total of over 400 kilogrammes (882 pounds) of infant formula into mainland China. Hong Kong barred peopl ... read more


FARM NEWS
More BARREL Balloons Take to the Skies

China's HD observation satellite opens its eyes

UAE to launch indigenous satellite in 2017

SAR images acquired by KOMPSAT-5

FARM NEWS
China to upgrade homegrown GPS to improve accuracy

Beidou to cover world by 2020 with 30 satellites

Obama bans construction of GLONASS stations in US without Pentagon's approval

US bans Russia's GLONASS for spying fears

FARM NEWS
Brazil moves to evict invaders from Amazon's Awa lands

Indonesia struggles to clean up corrupt forestry sector

Mangrove forests march up Florida coast as killing frosts decrease

With few hard frosts, tropical mangroves push north

FARM NEWS
Inexpensive technique could drive down costs of biofuel production

York scientists' significant step forward in biofuels quest

Seaweed Energy Solutions (SES) acquires wild seaweed operation in Norway

Algae to crude oil: Million-year natural process takes minutes in the lab

FARM NEWS
Canadian Solar Connects its Tumushuke 30MW Solar Power Plant to the China State Grid

Yingli Green Energy Supplies 1 MW of Solar Panels to Serbia's Second Largest Solar Project

ReneSola Panels Power 420MW Solar Project in Japan

KYOCERA Solar Captures Sun and Creates Shade at Tucson Airport

FARM NEWS
Researchers Find Ways To Minimize Power Grid Disruptions From Wind Power

Bolivia opens China-built wind power plant

Austria's wind industry laments new zoning restrictions

Wind energy: TUV Rheinland certifies PowerWind wind turbines

FARM NEWS
China coal mine accidents kill 1,049 in 2013: govt

Australia gives environmental nod to $5.7 bln coal project

Top German court throws out suit over giant coal mine

Australian coal projects at risk of being 'stranded'

FARM NEWS
Chinese Good Samaritan kills himself over accusations

Chinese state TV eyes Tiananmen rocker for gala: manager

14 killed in China mosque stampede: Xinhua

South Koreans trek to China to see their sacred mountain




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement