DAIRY farmers have been turning to a new feed additive to help cows beat the summer heat.
Last year, about 80,000 cows were fed Bos Koolus Betaine, a substance to enhance animals' water retention, mixed in with their bail feed or total mix ration.
This year, experts predict the number of cows consuming feed containing the white, crystal-like additive will rise to 200,000.
Romsey Feedworks ruminant nutritionist, Ian Sawyer, said the beef industry began experimenting with Betaine up to six years ago and it was introduced to dairy herds in 2007.
While still in the "growth phases", the science and cost-effectiveness of the product, which stems from a sugarbeet plant similar to sugar cane, has many farmers intrigued.
At about $7/kg or 10-12c a cow per day, Mr Sawyer said farmers viewed the additive as economical in summer, as it could save up to two litres a day in lost production.
It could also bring cost savings by helping cows recover quickly from a heatwave.
Betaine works by reducing animals' energy requirements during hot weather by allowing them to "hold hydration" in the face of heat stress.
This means they use less energy to cool themselves and have more energy for eating and digesting, to produce more milk.
Mr Sawyer recommended farmers add the product to their animals' feed for a minimum of three days or up to a week before a hot period. Depending on the size of the animal, each cow required 15-20g a day.
However, Dairy Australia's Grains2Milk program leader, Steve Little, said shade and a sprinkler system should be farmers' first priorities when keeping their herd cool.
"There is no single strategy, whether nutritional or otherwise," Dr Little said.
But he said supplements such as Betaine, as well as quality feed, were important, and he expected the use of the cooling agent to increase in the next few years as dairy farmers looked at additional ways to protect their milking cows.
"A lot more focus needs to be placed on nutritional strategies during the summer, such as high-quality fibre, having enough protein (and) optimising mineral inputs," he said.
