If successful, the research could lead to a more environmentally-sustainable product and reduced transport and processing costs.
The Dairy UP team is exploring ways to influence lactose production to reduce the amount of water in milk, while maintaining production of milk solids.
Project lead Juan Gargiulo said lactose played a key role in determining milk’s water content.
“We’re investigating the theory that those cows that produce less lactose would produce milk with less water and higher concentrations of solids,” Juan said.
“As milk is 87 per cent water, producing milk with less water is an opportunity for the dairy industry to improve its carbon footprint, reduce energy costs and improve water use efficiency.”
The project builds on earlier work in California led by Dairy UP collaborator Russ Hovey that demonstrated it was possible to reduce the lactose in milk production without negatively affecting total milk solids output.
It is an international collaboration, with Australian Dairy UP researchers investigating factors that influence lactose secretion in the cow, and University of California researchers aiming to better understand lactose synthesis and how it is regulated.
The Australian researchers are looking at the influence of milk composition, genetics and environmental conditions by analysing millions of records from Dairy UP monitor farms, NSW herd test results and DataGene’s Central Data Repository.
Results to date show significant variations across breeds, lactation stages, number of calvings and seasonal conditions.
Juan said Dairy UP’s research had identified cows that consistently produced milk with reduced lactose content or yield while maintaining similar fat and protein levels.
“These findings indicate there could be opportunities to improve milk production efficiency by enhancing milk composition and reducing water content,” he said.
The research shows that stage of lactation has a strong impact on lactose output, peaking in early lactation and decreasing as the lactation continues, and that hot, humid weather negatively affects yield of milk, lactose and milk solids, but did not affect lactose percentage or other milk components.
Holsteins had the highest lactose yields, while Jerseys had the lowest lactose yields and produced more milk solids per unit of lactose.
Juan said the findings highlighted the potential for selective breeding for cows that produce less lactose, more milk solids and less milk volume.
“Lactose production could potentially be influenced through genetics, nutrition or other interventions,” he said.
The findings also highlight the potential to develop management strategies to influence lactose production and enhance the milk production efficiency of cows.
“The ability to influence lactose production has broad implications for improving the cow’s energy balance, reproduction, milking persistency, genetics, milk quality and animal welfare,” Juan said.
The research is continuing with an in-depth analysis of cows that have shown reduced lactose production and milk volume and higher milk solids.
For more information, visit: www.dairyup.com.au