Hot milk

Remember yesterday’s 41 degree Celsius heat? Now, imagine you were standing outside in it being blasted by 250 1500-watt hair dryers. How do you feel now? Ready to do athletics?

Grazing the lush crop

Icy poles for cows

Believe it or not, each of our dairy cows gives off body heat equivalent to a 1500-watt hair dryer on a hot day. Yet, incredibly, each still made an average of 29 litres of milk for us yesterday. We nursed them through with some very careful planning based on the principles of the Cool Cows program.

  • Wayne got up an hour earlier to milk before the sun’s rays began to sting and milked two hours later than usual. This meant that the cows spent less time in the sun on the concrete yard waiting to be milked.
  • We hosed the whole yard down about 45 minutes before the afternoon milking. It’s amazing how much cooler the yard felt afterwards.
  • The yard sprinklers were activated as the cows came towards the yard. (You remember the fun of dancing through sprinklers on the lawn!)
  • The cows’ diet changed a little for the day. The cows got a little more grain, a little more green crop and a little less hay yesterday. It takes more energy to digest high-fibre foods, which adds to heat stress. Rather than feeding out the hay during the day, Wayne stayed up late and offered the cows a “night-cap” in the relative cool of the evening.
  • We chose the coolest paddock on the farm, ringed by the deep shade of mature willow trees.
  • On a hot day, dairy cows can slurp up a staggering 250 litres each. Our extra-large troughs ensured they had plenty of fresh, cool water to drink when they chose to emerge from their hideouts.

Poor girls. According to the Cool Cows program leader, Dr Steve Little, dairy cows start to seek out shade when it gets to about 25 degrees C. I think the farm’s cows, dogs and humans all felt the need to go into summer hibernation yesterday.

Our cows are so cool

Our cows are dignified ladies who like to keep their cool in more ways than one. Bred in cooler climes than Australia, Holstein Friesians start to feel the heat once the mercury climbs over 25 degrees Celsius.

We’ve been really busy preparing the farm to help them deal with hot summer days:

  • planting thousands of trees for shade

    New plantation for shade and wildlife

    New plantations will provide shade for the cows and corridors for wildlife

  • installing 4 kilometres of large capacity water pipes and 17 massive water troughs. Milking cows can drink up to 250 litres each on a hot day or 20 litres in a minute!

    Water trough

    Installing water troughs has been a 3 year project

  • putting up sprinklers in the dairy yard to offer a cool shower while they wait to be milked and

    Yard sprinkler

    A shower cools the cows, the concrete underfoot and offers relief from flies

  • adding salt, minerals and zinc to their diets.

    Feed in the bail

    Zinc is added to the cows' feed during summer

I also select the paddock for the day with a keen eye on the forecast. Today is pretty uncomfortable, so they’ve been sent to a paddock ringed with trees and will graze a more open paddock tonight.

Cool cows are happy, healthy cows who make more milk, suffer fewer illnesses, carry pregnancies better and are nicer to work alongside! Dairy research body, Dairy Australia, has done lots of work on heat stress in dairy cows and you can access lots of useful info at the Cool Cows website.