Thu, 21 Sep 2017

INDUSTRY ARTICLES

Genetics discovery looking at cutting nitrogen leaching across national dairy herd – CRV Ambreed
Wednesday, 29 March 2017

 
Angus Haslett and Phil Beatson of CRV Ambreed 

CRV Ambreed has made a genetic discovery it anticipates will reduce nitrogen leaching on New Zealand farms by 20% within 20 years and result in a more sustainable dairy industry.

In what’s thought to be an international first, the dairy herd improvement company has announced it will market bulls that are desirable for traditional traits as well as being genetically superior for a new trait that is related to the amount of urea nitrogen in milk.

CRV Ambreed is now selling semen from bulls whose daughters will have reduced concentration of Milk Urea Nitrogen (MUN) under the LowN Sires™ brand. MUN is a measure of the amount of nitrogen contained as milk urea, and CRV Ambreed R&D Manager Phil Beatson says there’s overwhelming international evidence of a direct connection between MUN and the amount of nitrogen excreted in urine when fed different diets.

“If this connection carries over, cows bred for lower levels of MUN are expected to excrete less nitrogen in their urine which will, in turn, reduce the amount of nitrogen leached from grazed pasture,” Mr Beatson says. “Daughters of CRV Ambreed’s 2017 LowN Sires™ could potentially save New Zealand 10 million kilograms in nitrogen leaching a year, based on the national herd number of 6.5 million dairy cattle.”

He says CRV Ambreed’s projections indicate that it’s possible to breed cattle that will reduce nitrogen leaching by 20% within 20 years.

The primary cause of nitrogen leached into the ground and waterways comes from the cow’s urine being concentrated onto patches of land. Some of the nitrogen excreted is converted to gas, some is taken up by plants, and a substantial amount is leached with soil-type affecting the proportion that is leached.

CRV Ambreed has been researching the connection between MUN and nitrogen in urine for five years and has now identified more than 20 existing, high-quality and top-performing CRV Ambreed bulls with the desirable genetic makeup for low levels of MUN. Hundreds of thousands of straws of semen are now available from the LowN Sires team. “It’s exciting news for farmers, the potential that they can help meet their environmental compliance through breeding,” Mr Beatson says.

The link between MUN and lower nitrogen output has been acknowledged before in international research, but this is thought to be the first time in the world the specific trait has been bred for and promoted, the company says.

Mr Beatson says CRV Ambreed research looked specifically at what could be done around Urinary Nitrogen (UN). Nitrogen taken in by cows in their diet is converted into five areas:  Milk protein (+ urea); growth (muscle is protein); dung; gases and also urine – the most interesting from an environmental perspective.

Since 2012, CRV Ambreed has looked at the MUN concentration in 650,000 milk samples and analysed them to understand what is inherited, and to create a MUN value for all animals.

Mr Beatson says farmers who already herd-test and herd-record with CRV Ambreed will automatically get the MUN values of their cows from June. This will help with decisions around culling or keeping cows for AI using bulls with good MUN values. Farmers who begin to herd-test and herd-record with CRV Ambreed from June 2017 will have their herd’s MUN values by the end of the year.

CRV Ambreed’s Managing Director Angus Haslett says farmers are encouraged to start the journey to greener cows now as improved offspring will be born in 2018 and will have their first lactation in 2020.

He says while there is a vast amount of research being conducted in New Zealand to mitigate nitrogen leaching, it makes sense to breed cows that produce less nitrogen in their urine from economic and environmental viewpoints.

“We know farmers are doing everything they can to mitigate nitrogen leaching and meet environmental compliance levels. The beauty about the genetic approach is that it has an additive effect to other strategies a farmer might be taking to reduce nitrogen leaching. This CRV Ambreed announcement provides a long-term solution that fits within the standard AI mating programme,” Mr Haslett says.

“Genetics can produce great gains for farmers, and many farmers already choose our bulls to breed certain traits in their cows; this is another step on that journey of finding solutions in genetics rather than products.” CRV Ambreed is already known for its team of bulls that are helping breed higher tolerance to Facial Eczema and has also launched homozygous polled bulls, whose progeny do not require time-consuming and costly dis-budding.

Mr Haslett says there is still research to be done to further test and confirm the genetic development and CRV is working with DairyNZ, AgResearch and Lincoln University on this. CRV Ambreed is very positive about the potential benefits the discovery will deliver for farmers and the nation.

The genetic announcement has been welcomed by major industry players such as DairyNZ. DairyNZ Strategy and Investment Leader for Productivity, Dr Bruce Thorrold, says the potential for farmers to reduce nitrogen leaching by breeding cows with lower urinary nitrogen output is exciting.

“If the planned science proves the link between breeding for MUN and urinary nitrogen output, this would give farmers in nitrogen-limited regions such as Canterbury more options to reduce nitrogen leaching without going away from a pasture-based system. Animal breeding would potentially add to gains from DairyNZ investment in research on managing nitrogen inputs, using stand-off and finding plants with lower nitrogen content.”

Waikato farmer John Hayward, who runs Judge Valley Dairies Ltd with wife Susan O’Regan, says the world now expects farmers to be looking after the environment. “It’s not just at home in New Zealand but internationally – around the world – customers expect the environment to be a priority.”

Judge Valley Dairies Ltd was the 2016 Supreme Winners of the Waikato Farm Environment Awards. Mr Hayward says CRV Ambreed’s genetics breakthrough “is a whole other level” and will help ensure farmers can manage the environment sustainably. “We, as farmers, still have to milk our cows and manage our pastures and ensure we run effective and profitable farm businesses, but this means we can still do that and take care of our land and waterways.”

He says the forecast potential reduction in nitrogen leaching of 20% within 20 years is impressive. “It’s a massive drop, and if we can achieve that, that means farmers don’t have to do anything different than the good work they are already doing in regards to the environment. It’s just about selecting the bulls with the genetic advantage to make this big impact on the levels of nitrogen excreted into pastures.”

CRV Ambreed has already briefed some of New Zealand’s regional councils about the discovery because many regional councils work with farmers around nitrogen leaching.

For more information, visit www.crv4all.co.nz/lownsires