Saturday, 28 November 2015 13:56

Adding BCS to BW

Written by 

The addition of body condition score to breeding worth in February will accelerate the rate of genetic gain in New Zealand dairy cows, says DairyNZ.

Following ten years of research, body condition score (BCS) will in February be incorporated into breeding worth; it recognises the value of a cow's ability to hold onto body condition into late lactation.

New Zealand Animal Evaluation Ltd (NZAEL), a wholly owned subsidiary of DairyNZ, did research in late 2014 which determined this value to be $107 per late lactation BCS.

This research project followed a 2013 review of the national breeding objective (NBO) where farmers indicated that they saw a cow's BCS in late lactation as an important trait.

The economic value is driven by the remedial actions a farmer needs to take with lighter cows through autumn and winter, to get them up to BCS 5.0 before the start of calving. Achieving BCS targets is important because cows that calve in poor condition will be compromised for the subsequent season.

This change to BW is estimated to result in only minimal shifts for most herds and bulls ($0-$15). It is predicted that the new eight trait BW index will lead to faster genetic gain in the national herd.

DairyNZ's latest monthly newsletter Inside Dairy reports Waikato lower order sharemilkers Shane and Lynda Campbell saying they have been ahead of the curve in recognising the value of BCS in the 450-cow herd they milk near Matamata.

They have local veterinarian and accredited BCS assessor Katrina Roberts visit once a month. She reports on the spread of cow BCS and the changes since her last visit, and makes recommendations for the coming months.

The Campbells run almost half the herd as a separate mob containing the heifers and thinner cows. When cows' BCS is recorded as falling to 4.0 or below they are drafted out of the main herd. In the second mob they are fed an extra 2-3kgDM/day.

Campbell says he is looking forward to seeing the BCS trait incorporated into BW and believes it will confirm much of what he has witnessed in past years of recording BCS in their $132 BW herd.

"The top cows' condition seems to fall off a lot quicker over lactation. By putting the BCS trait into BW, that puts a value on their ability
to hold that condition, especially later in lactation. If you can get a cow that can milk well, and hold BCS, it has to be a worthwhile trait to consider."

They aim to get 300 days in milk, but he says they also want to be realistic about the cows being up to BCS 5.0 for the start of following season.

He acknowledges the cost of drying off early or getting a lighter cow up to condition through winter. Last season they had 20 cows at less than BCS 4.0 in February that needed drying off.

"We have established that those 20 cows cost us $12,500 in lost production and extra feed." His calculation is based on a milk price of $5.50/kgMS and a feed cost of $250/t of dry matter.

With several years of BCS history behind his herd, Campbell is also interested in the heritability of BCS from mother to daughter. He notices that cows that lose their weight quickly tend to produce heifers that do the same.

"It will be good to see the BCS numbers in the BW backing up what we are observing in the herd every season," says Campbell.

More like this

Musical chairs

OPINION: DairyNZ's director elections has seen scientist Jacqueline Rowarth re-elected for another three-year term.

DairyNZ levy to increase?

Retiring chair Jim van der Poel has used his final AGM to announce the intention to increase the DairyNZ farmer levy for the first time in the industry-good body's 17-year history.

Tributes to retiring 'Jim the farmer'

Doing what is right, not what is easy, has been the hallmark of Jim van der Poel's leadership of, and advocacy for, the dairy industry, attendees at the DairyNZ annual general meeting heard last week.

Featured

New ag degrees at Massey

Changing skill demands and new job opportunities in the primary sector have prompted Massey University to create a new degree course and add a significant major into another in 2025.

The show is on!

It was bringing in a new Canterbury A&P Association (CAPA) show board, more in tune with the CAPA general committee, that has ensured that Christchurch will have a show this year, says CAPA general committee president Bryce Murray.

National

'Quite a journey'

Former Synlait chief executive Grant Watson says the past two years have been quite the journey.

DairyNZ levy to increase?

Retiring chair Jim van der Poel has used his final AGM to announce the intention to increase the DairyNZ farmer…

Former Fonterra CEO dies

Former Fonterra chief executive Theo Spierings passed away in the Netherlands over the weekend.

Machinery & Products

Milk Sustainability Centre launched

The recently announced Milk Sustainability Centre – a collaboration between global giant John Deere and milking and feed specialists De…

Data connection made easier

New Holland and Case IH are introducing new advancements in their precision technology stack to make farming easier and more…

» Latest Print Issues Online

Milking It

Feed from farmers

OPINION: The country's dairy farmers will now also have a hand in providing free lunch for schools.

Brighter future

OPINION: The abrupt departure of Synlait chief executive Grant Watson could be a sign that Chinese company Bright Dairy, the…

» Connect with Dairy News

» eNewsletter

Subscribe to our weekly newsletter