Here’s a look at how surprise sunshine can affect your livestock, and what you can do to prevent it.
Animals with darker coats are more likely to overheat in unusually warm weather and will display symptoms of heat stress. It’s said a cow will suffer ‘mild’ heat stress at a
temperature of 25 degrees with humidity of 60%. You can read more on the symptoms and the effects of heat stress here. Heat stress, if unrelieved, goes on to become heat stroke
(loss of consciousness due to failure to regulate body temperature), which can easily be fatal. Sheep and goats are less susceptible to this than other ruminants.
Younger animals will be most susceptible, and it’s worth bearing in mind that extremes in environmental temperature will impact negatively on animal if they are already unwell.
Heat stroke is more likely to be fatal for very young stock who may not yet be drinking water as they can quickly become dehydrated and weak.
It’s vital that very young animals have shade.
If your pasture is unsheltered you might consider making calf hutches available to young stock or rig an improvised shelter using tarp or canvas – ideally an adequate shelter
should be one that all livestock can use at the same time. If the heat is relentless you could consider housing them during the hottest part of the day.
Access to enough clean water is paramount for your stock to cope in heat. There are two variables to consider - cattle will drink more volume to cool down.
High-yielding cows may drink up to 200 litres of water in a day.
Secondly, the water source may be at risk of drying up or evaporating quickly in the sun. Be sure to check regularly that your water sources are still good.
Proper water accessibility would mean that at least 10% of the herd can drink at any given time.
Adding some salt to any rations may be helpful in preventing ruminal acidocis. The acidocis is a consequence of feeding at inopportune times – you may have to adjust
your feeding schedule so that cattle can digest rations in cool periods, and secondly, adjust the volume or energy content of rations. Since digestion is affected by body temperature,
less concentrates are advised. Cattle can also lose their appetite in hot weather, this may lead to a decrease in body condition, which can then affect their fertility.
See Animal Husbandry for Hot Weather-Sunburn here