One of the challenges in the farrowing house is to maintain the correct temperature for both the sow and the piglets. Sows need a temperature of around 22°C during farrowing and 18-20°C thereafter, while piglets require around 34°C when they are born and about 28-30°C in the following days.
This is very important for two reasons. Firstly, if a sow is in an environment that is too warm (outside of their comfort zone), it will be a challenge for them to consume enough feed, thus negatively impacting milk production. In addition, a colder room temperature will encourage piglets to sleep in the warmer areas, instead of close to the sow. This will help reduce mortality due to crushing. At the same time, making sure that the piglets are in their own comfort zone will help to avoid hypothermia, having a significant effect on their vitality and lowering the overall pre-weaning mortality.
Different tools are available to improve the “micro-climate” for the piglet
Traditional heat lamps are simple to find and to use, and are usually affordable. It is quite easy to move them around, in order to quickly provide heat to the piglets. But they have shortcomings as well. The main weakness is that the warm air rises, so energy is lost, and the area which is warm enough for the piglets is rather small. The risk is to place them too close to the piglets, increasing chance of harm as they can suffer from severe burns.
Radiant heaters can be an interesting alternative because they are usually equipped with thermostats, allowing to control the temperature according to the needs of the piglets (which evolve with age). Although they are more expensive than traditional heat lamps, the possibility to control temperature more precisely leads to a significant reduction in energy costs. Another advantage is that radiant heaters are wider and cover a larger area than heat lamps. Last but not least, as they do not produce light, it is less troublesome for piglets as they prefer to sleep in the dark.
Heat pads are a different option. Depending on the model, they get their energy from electricity or hot water. They must be positioned on the pen floor, where piglets will rest. Similar to radiant heaters, they offer the possibility to regulate the temperature and save energy. They cover a large area, where the temperature is uniform, ensuring all piglets can benefit from it. The usual recommendation is to have at least 0.03 square meter (30 x 10 centimetres) per piglet. Since warm air rises, less energy is lost than with the other systems. There is also less risk of injury to the piglets when compared to the previous options. Their main drawbacks are the cost to install, but according to their suppliers they can be used much longer than lamps or heaters. Last but not least, it is more difficult to move them once the piglets are born.
In conclusion, it is important to use supplementary heating to maintain temperature at the piglet level, because if it falls below their lower critical temperature (LCT), mortality rates will increase. This is why the additional cost of a proper heating system is justified in many situations.