Are your sheds properly ventilated? Here’s how to check – and how to improve them
The recent heavy rain across the country has ended any hopes of extended late grazing. Livestock farming isn't the only sector affected; cereal sowing and potato and beet harvesting have also ground to a halt.
One pressing issue I've noticed on many farms is the stress housed animals are under due to unseasonably warm temperatures and poor ventilation. Farmers and vets are reporting a significant increase in viral outbreaks and bacterial hoof infections.
Historically, ventilation has been a low priority for Irish farmers. Traditional cattle byres were effective for several reasons, including lower stocking rates and specific feed regimes. However, increasing stocking rates and more intensive feeding, coupled with higher autumn temperatures, are now contributing to rising viral and bacterial infection rates in housed animals.
Poorly designed buildings are a significant contributor to poor ventilation, aside from uncontrollable factors like warm temperatures and lack of wind. In the late 1970s and 1980s, there was a surge in the construction of slatted houses with low eaves and low roof pitch, which didn't prioritize ventilation. Despite this, these houses generally functioned well due to the absence of some prevalent viruses at the time.
The proliferation of grant-supported building in the 1990s and 2000s led to improvements in general design, with increased air space and light. However, the overuse of side sheeting impeded ventilation and air movement, relying on spacing between the roof sheeting to create a 'stack effect'. This is often inadequate.
I recommend a simple smoke bomb test to gauge ventilation. Set off a smoke bomb in all cattle houses on an average day, without strong winds. In a well-ventilated building, the smoke should be drawn to the highest points and vented out, indicating good air movement and the intake of fresh air. If smoke dissipation isn't occurring, consider mechanical ventilation systems, which are a specialist area. Farmers should engage experts for guidance on the most suitable solutions, whether mechanical ventilation or roof or side-sheeting design changes.
The most immediate solution is installing fans or wind tubes, but these are more expensive than natural ventilation systems. In recent weeks, I've seen large extractor fans used effectively in older, lower-pitched buildings, while strategically placed circulation fans work best in more recently constructed but poorly ventilated buildings.
Apart from the risk of disease infection, poor ventilation impedes animal performance. Increased body temperature and sweating cause discomfort. Shaving the animal's back can alleviate raised body temperature, but this task often gets overlooked on busy farms.
