Cows and Water

With the warmer weather slowly creeping upon us, it’s time to be thinking about the water that your cows have available, be it in the shed or in the paddock! Just remember though water is important at any time of year because it is the main component of milk, making up over 90% of its composition.

One of the best ways to reduce heat stress during the summer is to ensure a ready supply & access to clean fresh water.  Why is this?  It is because of the 200 litres that cows will drink during the day, a cow will sweat 50 litres of water through their lungs to cool themselves down.  If they don’t drink water, they can’t cool down!

While the cows are housed during the winter, they usually don’t have far to travel to access water; it is important to remember that studies have found that cows will not travel more than 150-200m for water.  In effect they are ‘lazy’ and will stay where they are despite their thirst.  Also, at any time there should be enough space for 10% of the herd to be able to drink at any one time, i.e. 20 cows in a herd of 200 cows.

A good flow of water is also required as cows will drink 20 litres per minute and studies have found that a 40% reduction in water intake will reduce milk output by 25%.  Cows also like to drink from troughs that have a minimum depth of 70mm, ideally 300mm, so that they are not gulping air as they drink.  Cows prefer a large, calm drinking surface from a clean trough.

Even with plenty of water available are the cows drinking it?  Is it palatable?  Just stand and watch a cow drink.  Cows are more sensitive to tainted water than we are, so if you will not drink from the trough then they certainly will not!  Cows usually taste the water initially with a couple of flicks of the tongue to test for taste & temperature and if happy will then take big gulps of water.  If they are not doing this then something is wrong with the palatability of your water.

Look at your cows as you get them in, do they have wet muzzles with plenty of froth?  Or are they dry?  Again, this is a sign they aren’t drinking enough.

One final tip must be to ensure that every time any stock is moved that the trough is flowing etc.  A broken arm/ball may lead to water overflowing, leading to insufficient water reaching other parts of the farm, as well as the potential cost of the wasted water.  Slow flow may indicate a leak elsewhere or a twisted inlet may prevent any flow.

If you wish to discuss your cow’s water requirements, or to discuss the supply of pipe & troughs etc., call FAR registered Dairy Nutritionist & CowSignals® Master Andrew Jones on 07717 44288 or e-mail