Dr. Brett Ramirez of the Iowa State University told producers at the 2020 Manitoba Swine Seminar the goal of ventilation in winter is to maintain proper relative humidity and concentrations of noxious gasses and in the summer to maintain a temperature that will keep the pigs thermally comfortable. Ventilation in today’s modern production systems is critical. It is really important for the pigs, the people, the environment, and all these different aspects related to it.
Dr. Ramirez said there are two significant challenges during cold weather. One is maintaining a thermally comfortable indoor environment, temperature, moisture, gas concentrations and also conserving energy to help keep operating costs down. There’s a delicate balance between maintaining those proper thermal conditions and acceptable levels of air quality with those cost-effective management strategies.
“If we have poor ventilation during these times, we can reduce building integrity, pig performance, drive up those heating and electrical costs and amplify all these other health effects inside the barn,” he said.
Rarely is ventilation the number one cause of costly problems with the barn, but it’s a factor that amplifies or can be a tool to help mediate situations and can drive up heating costs.
Ramirez said poor maintenance and management of equipment could have heaters and fans run inefficiently. Poor air quality and too much moisture or too dry inside the barn in winter can lead to potential upper respiratory problems with pigs.
“It comes down to profitability, making sure all those pieces are in place to maintain a profitable operation.”
He described the ventilation system by first tracing the path of the air. There is a primary opening on the outside of the barn to let in the fresh air. This opening could be on a soffit, gable end, wherever that air comes in. Next, the inlet for distributing fresh air, either in the ceiling or on the sidewall to help mix in that cold outside air with the warm moist barn air.
The system has a set of smaller fans for the minimum or low stage numbers to provide the fresh air exchange inside the barn operating on a static pressure to drive, which is the driver of ventilation, and those fans exhaust the air to the outside.
Dr. Ramirez said there are five things associated with cold-weather ventilation a producer needs to watch. Global temperature in the room, too cold or too warm with an adjustment to temperature settings, making sure the sensors are in the right spot and that the barn is well sealed and tight. Watch for cold drafts, especially if the barn has small pigs starting in the cold winter months.
“Make sure that those cold drafts aren’t dropping on pigs or causing them to be uncomfortable or locate and pile in certain parts of the barn that are undesirable,” he said.
A producer must check for excess moisture that can cause condensation forming on the building surfaces. Shifting the room temperature, ventilation rate or check ceiling insulation as a loose-fill can change that might cause those surfaces to be cold and then condensation forming, which will lead to premature wear on equipment and materials. Also, if that condensation is possibly near exhaust fans, those fans need to be sealed better, and covers or plastic on the fans help a bit.
Another point is checking for gas or odour that is noxious and undesirable, solved with improving air distribution or mixing in the barn, making sure the minimum ventilation rate is adequate and increased, if needed, to reduce those concentrations. And lastly, being on the lookout for static pressure, and to remedy this and critical, making sure to seal the infiltration locations.
Dr. Ramirez said the keys to proper maintenance is to be aware and to develop an intuition for ventilation, going through the barn with a mindset of, “I’m going to focus on ventilation,” while doing thousands of other things every day. Honing in on ventilation will help separate it from all the other tasks and help get things done timely and correctly. He recommends taking the time to know the settings and not guessing the proper settings. That comes through knowing the equipment and having the tools or sensors or handheld devices, whatever works and training the employees how to use them, too — the more people that know the more effective the management.
When everyone knows what to do, prepare a checklist for each season.
“This gives people almost a to-do list as we transition out of winter or into winter, into summer, out of summer, of certain forgotten pieces of equipment to get those backup and going the way they need to be for good operation,” he said. •
— By Harry Siemens
