Dairy Australia - Milk acetone research sniffs out sick cows

A new finding by a young Australian dairy researcher could offer a quick way of detecting sick cows before they show traditional symptoms.

Cameron Clark studied milk acetone levels of dairy cows in early lactation within the University of Sydney herd at Camden.

His work, funded by Australian dairy farmers through their Dairy Service Levy, studied milk acetone levels and found happy and healthy cows followed a regular cycle.

Sick cows however, recorded disrupted cycles of acetone levels in their milk.

“Sick animals were identified by their milk acetone level before we could observe any other symptoms,” he said.

A cow creates acetone when she uses body reserves not met by food intake to make milk. It generally reflects the animal’s energy balance.

Cameron said: “The findings from this study revealed that there was a lot of variation between cows and within cows in terms of acetone levels, with regular peaks about every three weeks.

“That’s a measurement that’s never been noted before. It’s the first time these patterns of cycle have been plotted,” he said.

The study revealed the effect of sub-clinical illness on milk acetone levels.

Cameron explained: “We had one cow with a left-displaced abomasum and the acetone levels went sky-high and remained high prior to the cow going off her feed or recording a significant drop in milk yield.

“Sustained, elevated milk acetone levels might be useful in determining overall animal metabolic health and allow early intervention.”

Cameron studied 70 cows through the critical first months of their lactation cycle. The Holsteins, from the herd at the University of Sydney’s Camden research farm, were fed pasture with 4kg supplement per day.

“We think the findings could have potential in automatic milking situations where there’s not as much human/cow interface. You could have one sensor for acetone on the milk line, instead of having multiple sensors.”

Further research, based on these findings, is being conducted by Helen Smith, a post-graduate student based at the University of Sydney.

BREAKOUT:

WHAT IS ACETONE?

Acetone is a natural by-product of the cow’s metabolism. It is formed in the liver when the cow uses body reserves as a source of energy.

Cameron explains: “Farmers may have smelled acetone on the breath of their sick cow as it is a volatile body.

“We’ve looked at the variation in feed intake between cows with similar milk production and found that some cows rely mostly on increased intake for increased milk production in early lactation while others rely too much on using body reserves.”