Pig ventilation systems are commonplace in the UK, yet their life after installation can often be overlooked. Environment specialist Tim Miller of ARM Buildings Ltd has been working closely with AHDB Pork to develop its ventilation videos, available on the Practical Pig App, and says regular maintenance is key to maximising ventilation efficiency.
Ventilation systems are intended to help provide optimum living conditions for pigs. A well-managed and efficient working system will draw fresh air into a building, and remove stale air that will contain a proportion of microbes, dust, harmful gases and water vapour.
“A system that’s effectively circulating air can really have positive impacts on health and performance which, ultimately, helps improve the bottom line,” Mr Miller says, adding that while the benefits are clear, producers should be aware that an inefficient ventilation system could have detrimental effects on productivity, particularly on hot days, and often adds to running costs.
“For these reasons, I’d urge all producers to make the maintenance of ventilation systems a priority on-farm. I often see situations in which a producer has invested a lot of capital installing a system, but then neglects the maintenance of it. This isn’t a best-practice approach and, in reality, maintenance doesn’t have to be expensive or time consuming.
“As with anything, little and often can bring with it long-term benefits and hopefully my advice for getting the most from a ventilation system, teamed with the new AHDB Pork videos, will help producers kick-start a maintenance programme.”
Many new buildings have a monitoring feature that looks at temperature regulation, power use and water use. Mr Miller says he’d urge producers to use this feature as it may help to pick up problems with the ventilation system.
Simlarly, routine servicing is something he says all units should ideally be doing on a yearly basis. The servicer should go through all components of the ventilation system to ensure that they’re working correctly.
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Tips for getting the most from your ventilation system
Inlets – Whether controlled or passive, it’s important to ensure that inlets are working effectively – from minimum ventilation through to maximum ventilation. If cords are used for positioning inlets, it’s essential to check they haven’t been stretched, as this can cause inlets to open more than required and cause an additional through flow. Often, if farmers have repaired the system or retied broken cords this will affect the inlet position. Therefore, resetting limits on positioning motors may be the solution.
Fans – The movement of fans shouldn’t be restricted and all blades need to be in good condition and clean to get the most benefit from them. It’s important that fan cleaning should be done with a dry brush and with the fan turned off. Also, whenever you’re working on equipment near to the fan, such as shutters, make sure the area is isolated so that the fan cannot be turned on.
Shutters – The accumulation of dirt and dust on shutter blades will restrict the throughput of air and will have negative impacts on the working of the overall system. For this reason, as with cleaning fans, a simple cleaning routine with a brush to remove excess dirt should be followed. For shutters mounted on fans that are on the outside of buildings, access is easy, however, for shutters mounted in fan chimneys, having a design that allows for the removal and cleaning of the shutter is ideal.
Chimney baffles – To ensure chimneys and baffles are operating efficiently they should be cleaned regularly to remove the build-up of dust and dirt. Also, when a fan isn’t in use, it’s important that baffles are sealed to stop the chimney acting as an inlet as this can increase the risk of draughts and therefore impact the entire ventilation system.
Alarms – When working correctly, an alarm system should notify workers of a problem within the building and, in turn, help to minimise any impacts on pig health. Although there are many options for notification, the important ones are high temperatures and mains failure. Many control systems incorporate battery backup to open inlets and baffles in an emergency. For this reason, weekly testing of systems is important. Batteries should be checked and replaced and, if possible, a routine inspection by an electrician is good practice.
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Reaping the benefits of ventilation
Although still in her 20s, with guidance from her father Robin, Rachael Bright has built up a thriving pig business, driven by her determination to maximise pig health and productivity by controlling the pigs’ housed environment.
The business, based on the family farm near Honiton, Devon, runs three sites with a 500-sow breeding unit, a weaner unit and a 4,000-capacity finishing unit.
“Controlling the pigs’ housed environment is about providing the best internal environment for the animals,” Ms Bright says. “Ultimately we want them to grow as efficiently as possible and, for this to happen, they need to be happy and healthy.
“If they’re living in conditions that aren’t quite right – too hot or too cold – because of poor ventilation management, it’s likely that you’ll see decreased feed conversion ratios (FCR) and therefore a reduction in performance is likely.”
Ms Bright explains that the farm installed fan assisted ventilation systems to improve the housed environment for their pigs and notes the growth benefits they have seen.
“We installed ceiling mounted fans in our weaner and finisher buildings around two years ago,” she adds. “The fans create a vacuum and control the movement of the air around the building.
“We can control the system by increasing or decreasing the speed of the fans depending on what’s required. In the weaners we’ve seen overall health improvements and improvements in growth rates.
“Although our ventilation system is relatively new, we don’t underestimate the importance of regular maintenance. We’re well aware that if the system is not operating correctly it could cost us a lot of money.
“That’s why we carry out maintenance on the system every 15th week, coinciding with new batches. We ensure that the fans are cleaned to remove any potential disease burden and that they’re working properly.”
Ms Bright is considering further investment in a new finishing shed with a ventilation system that extracts air from beneath the slats using fans located outside the shed.
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Ventilation videos and other AHDB resources
A series of new ventilation videos are available to download via the AHDB Practical Pig App at: http://practicalpig.ahdb.org.uk/ Written, narrated and demonstrated by Tim Miller, the video clips demonstrate practical management techniques specifically related to the importance of maintaining ventilation systems with the aim of maximising the bottom line.
There are also videos featuring consultant John Chambers available; search for ‘ventilation’ on the AHDB Pork YouTube channel at: https://www.youtube.com/user/bpex2010/featured
Guide to ventilation in straw-bedded buildings
The AHDB Pork guide Providing pigs with good ventilation in straw-bedded general purpose buildings can be downloaded at: http://pork.ahdb.org.uk/media/74240/ventilation-in-straw-bedded-general-purpose-buildings-aug-2015-update.pdf
Action for Productivity no. 21: Ventilation can be downloaded using the following link: http://pork.ahdb.org.uk/media/2048/Action-21-Ventilation.pdf