DataGene has introduced a new stand-alone breeding index called the Sustainability Index included in its August release of Australian Breeding Values.
The Sustainability Index ranks bulls according to their ability to reduce greenhouse gas emissions and increase milk production while also considering other vital profitability traits.
DataGene’s Peter Thurn said breeding for reduced greenhouse gas emission intensity didn’t mean compromising on other traits which underpin on-farm profitability.
“The Sustainability Index is highly correlated with the Balanced Performance Index; the top bulls on one, will be highly ranked on the other,” Mr Thurn said.
“It’s just a difference in weighting, and with the Sustainability Index, the weighting of feed saved and survival has tripled compared to the BPI. Looking at it from a financial perspective, the trade off in BPI over the next 25 years — if you select on the Sustainability Index instead — is about $1 a year for Holsteins and it’s even less for Jerseys.”
There are two ways to tackle greenhouse gas emissions on a dairy farm — reduce the total or gross emissions — or reduce the emission intensity.
The Sustainability Index focuses on reducing emission intensity, that is, decreasing the amount of carbon emitted relative to milk production.
This is calculated by dividing the amount of carbon emitted by the amount of milk produced.
“The reduction in emission intensity is achieved through a combination of dilution and increased efficiency, higher milk production from longer lived, more feed efficient cows means more milk per tonne of carbon,” Mr Thurn said.
“Reducing emissions intensity is a more practical approach as it does not diminish productivity, whereas a gross approach could lead to less productive and ultimately less profitable cows.
“Like any index, you can add a range of other traits to assist you to breed the type of cow you want in your herd. A good way to do this is to use DataGene’s Good Bulls App or the DataVat website.”