How building design is the key to better calf health

With many factors involved in rearing youngstock, housing design is often overlooked.

Playing a crucial role in the lifetime of a dairy or beef cow, sub-optimal calf housing can affect the trajectory of the calf’s future performance and productivity.

In this blog, animal welfare specialist Chloe Rodriguez shares expert advice on getting the most from your existing sheds, plus what to consider in new housing designs to maximise youngstock health.

Why housing matters

“The success of youngstock development depends on their very first day,” says Chloe.

“Creating the right environment from day one will mean higher production of milk in the future and there will be better herd longevity.”

When rearing calves, Chloe advises focussing on three main pillars for optimal calf health:

1. Immune system including colostrum management
2. Pathogen burden including within the animal and outside in the environment
3. The calf’s environmental conditions

“Each pillar helps the other, correcting environmental conditions can boost the immune system and reduce pathogen numbers, a simple solution can make a big impact,” she says.

Chloe says buildings are commonly designed for general purpose and not with calves in mind.

She explains: “Buildings are often draughty at calf level, making it hard to control the internal temperature.

“Integrating features from the start is ideal, but any building can be improved with retrofitted products, and prevention measures are highly recommended to reduce disease risk and costs, ensuring calves thrive.“

What to consider with housing design

Looking at housing holistically is key to improving overall calf health, Chloe says there are several contributing factors to consider:

Ventilation

Look for signs in your current sheds that show ventilation may not be adequate.

“A few signs of bad airflow include the smell of ammonia, condensation or cobwebs and calves may lie in a particular dryer area of the shed,” she says.

“The issue with calves is that they don’t generate enough heat to maintain the stacking effect, and as a result, the contaminated air isn’t expelled from the building, causing the calves to breathe it in.”

Calves are vulnerable to the cold, but Chloe says heat stress also poses a significant threat to youngstock.

“Any temperatures above 22°C can affect younger animals and cause the immune system to be suppressed, therefore maintaining optimal body temperature is key to ensure a productive animal,” she explains.

Airflow

Due to the UK having a maritime climate, it can be difficult to control airflow to maintain consistent ventilation all year round.

Chloe explains: “In winter, air needs to be ventilated within the environment six to eight times per hour and 40 – 60 times per hour in summer to replace any damp stale air.

“Still air is any air travelling less than 0.12m/s whereas a draught is any air travelling more than 0.3m/s, therefore even a slight breeze can be too much for calves.

“The aim is to get the right volume of air circulating through the shed and at the right speed to reduce disease potential as pathogens are killed 10 – 20 times faster in fresh air.”

Inlets

When designing a new building, air inlets need to be the right shape and size to ensure the air is drawn in correctly.

“The inlets need to be twice the size of the outlets to create a suction effect, there should be solid side walls of 1.2m below to reduce low-level draughts at calf height,” says Chloe.

“There are three types of fixed inlets available including Yorkshire boarding, space boarding and metal cladding which all have pros and cons.

“The other option is going down a mesh route where it can be fixed or automated, the automation means full flexibility to control the environment in any season.”

Automated mesh side curtain benefits:

• Full protection from the wind and driving rain
• Opens to allow natural ventilation in the warm weather
• Mesh fabric allows airflow even when closed

Outlets

Often overlooked, outlets are just as important as inlets as they provide the exit for warm contaminated air to escape.

Chloe says: “When installing outlets in new or older buildings, stocking density needs to be considered and if there are any plans for this size to expand in the future.

“The minimum outlet area for calves is 0.04 m² per calf up to 100 kg, so if calf numbers are likely to increase, it’s important to plan ahead and build in additional vents from the start.”

Ventilation solutions can be tailored to any building.

“We offer many ventilation solutions such as LightRidge which ventilates and naturally lights up the shed and Positive Pressure Tube Ventilation (PPTV) can be used which changes the air four to eight times per hour,” she says.

“Smoke tests are a great way to see how your air is behaving in your current sheds, we can visit your shed, then work out which direction the air naturally travels and work out the right product to use.”

Drainage and hygiene

A damp environment can cause cold stress in calves and can contribute to a higher pathogen load in the pens and increases disease risk.

“How to know if you have damp in your calf pens is by doing the knee-test, if you kneel and have damp patches then there is too much moisture for the calves,” she says.

Chloe’s guide to controlling damp:

1. Have deep straw beds
2. In the calf pens, have a steeper slope of 5% so fluids can drain away
3. Put the drainage channel at the end of the slope in front of pens
4. Make sure drains are clear and clean of any debris blocking them

Roof design, lighting and materials

Another consideration is roof design and making sure the calves have enough light but not too much.

“Shed roofs should slope 17 – 22°C to allow better ventilation and using fibre cement is ideal as it prevents condensation whereas tin can be prone to trapping moisture in the winter,” says Chloe.

Cows and calves need more than 200 lux of light for 16 –18 hours and less than 30 lux for 6-8 hours at night for their natural circadian rhythm.

“To prevent a greenhouse effect, where calves can overheat, roof lights should make up 10 – 15% of the total roof and up to 20% if north facing,” she adds.

The holistic approach

Success in upgrading an existing building and putting up a new building comes with careful planning Chloe says.

“Considering all factors and giving each one the same amount of planning will all contribute to the bigger picture and ensure success year after year,” explains Chloe.

“It is also worth monitoring the changes made to make sure that they are working as they should as any upgrades may need to be adjusted.

“The ultimate aim is healthy, thriving calves that grow efficiently into productive cows.”

Get in touch

Contact Chloe at crodriguez@galebreaker.com for personalised advice on improving your livestock housing and if you’re interested in Chloe’s on-farm advisory service.