Getting it Right: Temperature and Ventilation

Balance the relationship between air temperature and movement for maximum pig performance and profits.

Graphic showing relationship between temperature and air flow.

Maintaining optimal barn conditions is important for pig and barn staff well-being, and helps improve farm productivity.

While good ventilation improves humidity, dust and gas level conditions – promoting pig performance – ventilation rates must be managed carefully to ensure proper barn temperature is maintained. In the winter, the temperature of fresh wintry air intake must be balanced with proper heating management. Air exchange and temperature control should be managed separately year-round, according to our own PIC research and feedback from our customers.

Through our own research and in collaboration with our customers, PIC experts have learned many lessons on how to best manage air exchange and temperature control year-round. The most important point to share is this: air exchange and temperature control should be managed separately.

chart showing optimum temperature ranges at 60% humidity.

Different types of pigs have different optimum temperatures. Newborn piglets have a higher desired room temperature (DRT), or goal temperature of the barn, than older pigs. Also, younger pigs are more susceptible to temperature variations than older pigs.

When developing a temperature curve, DRT should be the focus.

It’s important to remember that no matter the time of the year, as wean-to-finish pigs grow and get larger, DRT is reduced from over 85°F to below 60°F (29.4°C to 15.5°C). Specific DRT numbers will depend on pig weight, health status, barn design and the use of a “comfort zone.” Please refer to Appendix A in our Wean-to-Finish Manual. If barn temperatures are too low, pigs must expend energy to keep themselves warm instead of converting feed into lean muscle. If barn temperatures are too high, pigs must expend energy into keeping their body temperature at acceptable levels, which can also result in reduced performance.

Graph showing desired room temperature for wean to finish pigs. 

The axis on the graph does not indicate Fahrenheit or Celsius. We recommend PIC clarify that on the web article graphic.

Comfort zone
On the other hand, an optimum barn temperature will result in minimum required heat generation and maximum growth rate and feed conversion. For young pigs, comfort zones are an effective way to keep pigs warm and keep ventilation rates where they need to be to maintain proper air exchange and humidity levels. Comfort zones are also important for special pens, inefficient barn heating systems and if the cost of heating is high.

When using piglet heaters, brooders and/or mats, comfort zones should be at 95°F (35°C) directly beneath the brooder for 14-to-21 days upon placement, dependent on pig size and health. Remember, pigs require 0.4 ft2 of mat space to maximize pig comfort and eliminate drafting from below the slats or plastic flooring.

Minimum ventilation
Good ventilation management in the winter months means maintaining a minimum ventilation rate while optimizing air flow to reduce energy losses.

Table showing minimum ventilation requirements by days on feed, weight of pig, and winter cubic feet per minute.

During summer months or during later stages of the ventilation system, our goals change from properly ventilating the barn to achieving proper air exchange and gas levels. Without burning excessive fuel, this is achieved by reducing the temperature in the barn to stay within the thermoneutral zone of the pig.

When barn temperature falls below a given set point, the ventilation system should be operating at the minimum setting. This is called minimum ventilation and is expressed as CFM/pig or CFM/lb., which is the minimum ventilation rate to remove the humidity and gases produced for the pigs. Likewise, when barn temperatures are above a given set point, the ventilation system should enter higher stages, allowing for more rapid air exchange rates as the goals begin to change.