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If you’re anything like me, you’ll know how it feels on a hot summer’s day when you’re busy working – you’ll often feel more tired and will likely be less productive. This is the same for animals, so making sure they’re kept cool during warm spells will ultimately help avoid any serious consequences to their performance and health.

All animals have what is known as a “Thermal Comfort Zone” – a range of temperature within which the animal’s comfort is optimal – and for dairy cows this falls between -13°C and +25°C, with a body temperature of between 38.4°C and 39.1°C.

At any given temperature, the apparent temperature – or how hot we feel – will increase as the humidity rises. As dairy cows can produce the equivalent heat of sixteen 100 watt light bulbs, it’s no wonder that during the hot summer period, they can often suffer from heat stress.

What are the consequences?
In the most serious scenarios, there is a real risk of death as a consequence of extreme heat and humidity. And while not all cases will be this extreme, the most common effect of heat stress in dairy cows is reduced milk production, which in turn can result in a loss of profits. It’s also important to remember that high yield animals are likely to suffer stress at a much lower temperature and humidity, so a solution should be in place at an early stage.

To help improve the welfare and productivity of cows, we are finding that more dairy farmers are investing in ventilation. During hot weather, increasing the air speed in the building not only increases the rate of air change, but can also improve the effectiveness of evaporative heat loss from the cows.

Which systems can help?
Suitable ventilation such as HV belt drive fans are capable of moving large volumes of air with minimal energy consumption. This form of heat stress management can help to remove warm stale air while introducing fresh outside air at a controlled rate.

Although ventilation may help, it is still not able to cool the air lower than the ambient temperature. In this case, we would suggest turning to an evaporating cooling system. The solution offered by Hydor introduces very small water droplets into the hot air and as the water evaporates, it rapidly cools the air inside the shed while ensuring it does not dampen any surfaces.

So, although cows are able to make adjustments to both their behaviour and body chemistry in an attempt to maintain their body temperature, it’s still important to make sure the temperature of the shed itself is well regulated during summer months to manage heat stress.

Duncan Burl, Managing Director at Hydor Ltd.