9th September 2021
What you need to know about repurposing a building into a calf shed
Repurposing an existing farm building to house calves can be an effective and low- cost option when transitioning to rearing a higher number of calves on-farm.
From autumn 2021, Red Tractor assured dairy farms will have 12 months to ensure no dairy bull calf is slaughtered until it is at least eight weeks old. For many farms, this will mean keeping a higher number of calves on-farm for longer and farmers will need to ensure they have capacity to do this. This is one of the many reasons why farmers may need more space for calves.
Buildings which have previously had a different use can often be repurposed into calf sheds, but it is important to make sure the converted building is fit for purpose. There are also some practical considerations, such as deciding on type of access needed.
What do calves need from housing?
Calves need an environment which is dry, warm, well ventilated but free from draughts and has sufficient space for the number of calves housed.
Sufficient pen space
If calves are grouped in pens, there needs to be enough space for each calf to access water and the milk feeding system to ensure smaller animals are not denied adequate nutrition from bullying. The same goes for weaned calves, there must be enough space for all animals in the group to access feed and forage.
Sufficient dry bedding will keep calves warm and help maintain growth rates during colder months. However, damp bedding can increase the risk of disease in calves. For example, the parasite which causes coccidiosis thrives in warm and damp conditions.
The right combination of weatherproofing and ventilation will achieve an environment in which bedding stays dry, reducing the risk of disease.
Flow of air through shed
Good ventilation is key to preventing pneumonia and ensuring respiratory health. Ideally, fresh air should come into the shed, flow through it without recirculating and pass back out. Recirculating air increases the risk of calves inhaling airborne viruses and bacteria which can lead to pneumonia.
Ventilation should be achieved without creating draughts. When draughts are present at calf level, animals are easily chilled which can lead to reduced feed efficiency and growth rates. They also increase vulnerability to infection, especially in winter, as calves divert energy to keep warm, which can lead to increased cases of pneumonia.
Key things to consider
There are several things to consider when converting an existing building into a calf shed. Practical aspects like how to access the shed will have an impact on the conditions once calves are inside. Considerations include:
1. Wind direction – where is the prevailing wind coming from? What is in place to protect calves from adverse weather? Are improvements needed? There are many weatherproofing solutions to protect livestock from windy and wet conditions.
2. Access – what access is needed? How will the shed be accessed day-to-day and is there vehicle access for mucking out? Access points can create draughts and vulnerability to weather conditions, but there are door options to overcome this.
3. Pen layout – how many pens will fit within the shed? How many calves to a pen? Group housing allows social interaction between calves enabling them to express normal calf behaviours. But calves housed in larger groups of more than six to eight animals to a pen are at increased risk of respiratory disease.
4. Ventilation – is natural ventilation sufficient to achieve good air flow? Some buildings can achieve optimal air flow with natural ventilation, whereas others need mechanical systems to ensure sufficient movement of fresh air into, through and out of the shed.
Mechanical ventilation is used to improve air flow within a building when natural ventilation is not sufficient. Fans can be used to increase air movement of air, however a ventilation tube system like VentTube Fresh achieves more consistent results. This is because the system can be tailored to the shed dimensions and the number of calves typically housed to optimise air flow. The system pushes stale warm air out of the shed and replaces it with fresh air, delivered at calf level.
When mechanical systems are used, it is recommended that a complete change of air occurs every 10-15 minutes to maximise air quality.
If converting a building for use as a calf shed, current ventilation should be assessed to help decide how to ensure an adequate flow of air for calves. The Galebreaker team use smoke machines to help detect draughts or hanging air to understand how air is moving through the shed. Contact us to arrange a ventilation assessment.