The icy clutches of winter can harm the welfare of your cattle. That’s why it’s best to move your herd indoors. But that comes with its own set of challenges, from nutrition to ventilation.
Overcoming these challenges is crucial to your profits. Here’s a rundown of some of the risks, with advice on how to manage them.
Wet, wet, wet? No, no, no.
Moisture and damp is best avoided. Harmful pathogens survive much better in damp, enclosed environments. Not what you want in your herd’s housing. Especially as the stress of moving indoors can temporarily weaken immune systems. Likewise if you have calves, the exodus to the cowshed may expose them to certain bacteria and viruses for the first time.
Moisture also reduces the air temperature, meaning your herd has to divert more energy to try and raise body temperature. That’s a waste of feed and could mean the condition of your herd deteriorates and/or growth rates slow. Keeping your herd warm is half the point of moving them indoors in the first place. Don’t let excess moisture scupper your intentions.
You get the idea. Excess moisture is something you should prevent. Repair leaky downpipes and broken water feeders. Avoid soaking feed areas when it comes to cleaning. And ensure pens have adequate drainage. You wouldn’t want to settle down for the night on a cold, soggy bed would you? Thought not.
Fresh is best...
Smelly, stale air? It’s about as fun for cowkind as it is for us humans. Without ventilation the air inside your housing can become infiltrated with pathogens and pollutants that could harm your herd. Ammonia in particular is a threat and can cause pneumonia and other breathing problems.
A circulation of fresh air will help to control temperature and humidity while removing pathogens and pollutants. That’s a quadruple-whammy of disease prevention. And with the help of some simple physics, this steady stream of lung-pleasing air can be generated naturally.
The ventilation benefits soon stack up...
You can drive natural ventilation in your herd housing thanks to the “stack effect”. Warm air from your cattle rises and leaves through outlets. This creates negative air pressure that draws in fresh air from the outside through inlets. And so the cycle continues.
The efficiency of the stack effect is determined by several factors:
- Area of outlet – roughly 0.04m2 for calves, rising to over 0.1m2 for adult cattle
- Design of outlet – open-ridge designs tend to enhance the stack effect
- Area of inlet – minimum 2x outlet area, ideally 4x outlet
- Position of inlet – if close to other buildings the ‘cleanliness’ of the incoming air could be reduced
- Pitch of roof – steeper pitches tend to enhance the stack effect
- Stocking density – small calves in large air spaces may not generate sufficient heat for the stack effect to work
Once full, you can check if your housing is driving the stack effect by deploying a smoke bomb. It should clear in less than a minute or so.
No joy? An alternative to the stack effect is a mechanical system such as a ventilator fan or extractor fan.
Either way, it’s best to speak to a specialist if you’re unsure. Good ventilation will help to prevent your profits disappearing into thin air.
Cold cows eat away at profits
A content cow’s body temperature hovers around the 38˚C mark. The harder they have to work to maintain that temperature, the more energy is diverted from growth or body condition maintenance to stay warm. Cold cows eat away at your potential profits. Almost literally. Excessive chill will also suppress your cows’ immune systems.
But be careful. Overheating your herd comes with risks too. Cows are susceptible to heat stress - did you know they can only sweat at 10% the rate of humans? - which can be fatal in extreme cases. Bottom line: balance is the watchword when it comes to air temperature in your herd’s winter housing.
Don’t forget to be wind-wary too. A stiff breeze - let alone a winter gale - can have a significant impact on ambient air temperature. In fact at a speed of just 2m/s the wind chill can reduce the lower critical temperature of your animals by as much as 9%.
So what can you do to tackle temperature problems?
- Check the temperature in the housing daily for excessive fluctuations.
- Watch out for cows that are shivering or have raised hair.
- Make sure no draughts can enter your cow housing at animal height.
- Keep your cows well supplied with fresh, dry bedding.
Feeding up to stay healthy
Exceptionally chilly winters can cause problems when it comes to feeding your cows. Out goes fresh grazing, in comes forage, grain and dietary supplements to keep your herd healthy and happy.
Knowing exactly how many calories - and which nutrients - your herd needs is a precise science. As you know, a bovine’s body works harder - and burns more calories - the colder it is. Cows may require up to 20% more food during the cold months of winter to maintain a healthy bodyweight.
Begin adapting your herd’s diet before winter hits. It’s much easier for cows to gain weight during the autumn. Besides it can take the microflora in the rumen three weeks to adjust to changes in rations or the nutrient makeup of food, during which time food may not be digested as efficiently as normal. Avoid dramatic dietary changes in favuor of the softly, softly approach.
Bulking out dietary plans with supplementary fat can help to tackle the calorie challenge head on. Megalac consists of a type of fat that improves a cow’s fertility and dairy yield, bypassing the rumen and going straight to where it’s needed. That can help your herd to better withstand cold snaps and maintain healthy body condition scores. Supplementing diets with Megalac can help to even out your feed costs too.
Over to you...
Ultimately the winter housing challenge is about protecting your herd, your profits, and your livelihood. With a few simple strategies, you can ensure your cows remain healthy while the temperatures fall, without the fear of your bottom line freezing over.