Tests with a cooling system for breeding sows during lactation yielded positive results, according to researchers at the Dutch Wageningen University and Research Centre.

The research was carried out at the practical centre of Sterksel during 2006 to 2008, at the request of the Dutch product board for livestock and meat and Nooyen Pig Flooring.

Sows in a breeding house having a cool sow system had a higher feed intake during lactation, on average 0.3 kilogrammes daily.

Sow weight loss was lower during lactation, on average 1.5 percent, but there was a seasonal effect. In summer weight loss was 3.5 percent on average, in winter there was no difference.

Piglet weaning weight was also higher, up 0.4 kilogrammes; however there was a seasonal effect as well, in summer weight was on average 0.5 kilogrammes and in winter 0.2 kilogrammes.

Positive effect was also resulted on the litter size in the next litter and breeding results of the piglets, on average yielding one more live pig in each new litter.

Economic advantage of the system, in this trial, was EUR13.30 (US$16.81) per sow yearly.

The housing temperature in farrowing houses is usually higher than 22 degree Celsius due to the heat sows emit. In these circumstances, sows have difficulties emitting more body heat, which could lead to a lower feed intake, which could degrade milk production, in turn leading to a slower piglet growth.

This will also cause sow weight loss during lactation, causing negative results in reproduction and cooling the sow's floor may contribute to the sow's thermical comfort.