A new intelligent heat source for piglets

05-04-2016 | Piglets | Pigs | Article

Piglets need warmth, but not always light – a newly developed, intelligent heat source provides only heat when piglets need it, thus eventually better meeting the pigs’ requirements as well as saving energy and money.

Every now and again, innovations are introduced of which one thinks – why didn’t anybody think of this before? After all, it is not rocket science to generate heat through different ways than light. Then why have heat lamps become common practice to help keep the youngest pigs warm in swine production?

Millions of lamps across Europe help heat a little zone where (especially newborn) piglets can lie, huddled together, as they prefer a much warmer environment than their mothers, who do best when being in a cooler environment. In Denmark, for instance, these lights are often provided inside a flap cover and in case the climate or weather asks for it, these lights can well be spotted in weaner pig houses as well.

Jens Volsmann, pig farmer, Skjern, Denmark: “I am happy to be able to do something for the pigs.”

Thinking beyond the standard heat lamp

Per Nielsen is a Danish engineer, who happened to be called into pig farms regularly to fix electronic problems. Having observed the heat lamps, he thought: there must be a better way to provide heat for the youngest piglets than this. He tells Pig Progress: “After all, do piglets like one heat source? One where it is very hot directly underneath, but getting colder quickly as soon as they are further away from the source? And are they happy to sleep when the light is on?”

These are rhetoric questions, if you ask Nielsen. He knew about alternative ways of how to generate heat, e.g. by radiation instead of light, and wondered if this could be applied to piglets. He says, “For me, the heat source had to meet 2 criteria: one is that heat should be distributed more equally – and that the system had to be responsive.” In other words: more equal distribution leads to a wider surface being warmed equally, so no piglet should have to suffer from hypothermia. Responsive means that the temperature can be adjusted to the growth stage of the piglets. In other words, getting less warm over time.

His thoughts eventually led to the eHeat, a 68 cm long, 19 cm wide, rectangular heating device based on – indeed – radiation, which can be built into piglet nest cover flaps. For this purpose, he established a small company called Animal Care.

Reducing energy usage

In order to get Animal Care acquainted to both long-standing experience in the livestock industry as well as large markets, Nielsen knocked on the door of Danish-based agricultural distribution company Grene-Kramp. The potential for the new finding was immediately acknowledged, says Torben Johnsen, product specialist.

The heater being responsive was drawn out in such a way that it will ensure the most heat just after birth (28°C), gradually going down to around 20°C after ten days. In addition, by use of a built-in thermostat, the device automatically switches off in case the surrounding environment already has the right temperatures. All in all, this leads to a substantial reduction of energy usage, Johnsen says, per pen from just over 25 kWh on day 1 after farrowing to just over 10 kWh on day 10 after farrowing.

Reinforced with practical tips from Grene-Kramp (e.g. the heater being equipped with a ‘plug & play’ function’, i.e. easy installation), the device eventually becomes green on top with light signals indicating it is functioning at that moment. With one push of a button, a ten-day cycle will start.

Choice of material was also a serious matter to think of, Nielsen says. Of course the material should be easy-to-clean. On top of that, the material should not melt when getting hot and it should not harm sows in case they mistake it for a snack. For that reason, the heat sources are made from heat-resistant PVC reinforced with fibreglass.

The radiation heat device is 68 cm in length.
[Photo: Vincent ter Beek]

Effects in the pig house

On a drawing table, an idea like this always looks good, but what counts is whether the system actually does add something to pig production in real life. To scientifically establish effects in the pig house, research was carried out at Aarhus University in 2013. Researchers Lene Juul Pedersen, Mona Lilian Vestbjerg Larsen and Karen Thodberg studied the effect of the new microclimate created underneath the covers, the outcomes were presented at the 48th Congress of the International Society for Applied Ethology, held in Vitoria-Gasteiz, Spain, 2014.

Firstly, they concluded that both room temperature as well as the new heat source have an impact on piglets’ use of the creep area, especially during the first days of life where piglets otherwise tend to stay at the sows udder. A relevant finding, as crushing often occurs in the first days after farrowing so there might be a direct effect to reduce preweaning mortality, see Figure 1.

Figure 1 – Percentage of piglets that used the creep area on day 1, 2 and 3 after farrowing.

Secondly, the researchers also found that the piglets also seemed to prefer to sleep in a dark area during night time – in fact just like in real life, also illustrated in Figure 2. Something that is possible with the new heat source, as it provides heat without light. The researchers wrote, “Thus to attract piglets to the creep area it is better to keep it dark. The new radiant eHeat can heat up the creep area without light, in contrast to the incandescent control lamp.”

Figure 2 – Percentage of piglets in the creep area summed for the day 1, 2, 3, 7, 14 and 21 after farrowing and is divided between observations in daylight and darkness.

Next steps in research now is to observe whether the increased use of the creep area and more optimal heat allocation also leads to e.g. increased piglet growth and decreased pig mortality. Trials on this are underway in a 400-sow private heard in Denmark, in combination with Agro Business Park.

The heat source in practice

The theory seems solid, science has proven its usage, and how do pig producers work with it? Jens Volsmann is a swine producer not far off Skjern in western Denmark. When he decided to revamp one of his farrowing houses almost two years ago, he took animal welfare as a starting point, he says. For that reason, the house was equipped with 42 free farrowing crates of 4.2 by 4.2 m and decided to wean at 28-29 days there. The additional space was necessary, as with increased genetics, sows produce more piglets – and with later weaning, the piglets are bigger once they leave the nest.

The farrowing places were equipped with the new heat sources. They warm up a substantially larger area than a light bulb. At the time of the visit, piglets had just been born and were still trying to find their bearings and for that reason were not as much under the cover as piglets in some trial films. Volsmann nevertheless is satisfied with the way eHeat has been working and he’s happy he can do something for the pigs, he says. “The technology was available, I had the feeling I should try something new.”

Volsmann admits he has not kept track of his energy rates and hasn’t noticed a reduction in mortality rates. About this last fact, he immediately adds that this is hard to measure as the novelty was added when in fact the entire pig house received a new management strategy. “So what we see might just be a compensation for the higher mortality due to the free farrowing approach. All in all, yes – I would definitely do it again.”