Pigs in Mud

1 May 2011 - It is a true picture of contentment, and now a scientist is suggesting that a pig's love of mud is more than just a way to keep cool. A researcher in the Netherlands has looked at wallowing behaviour in pigs' wild relatives to find out more about what motivates the animals to luxuriate in sludge.His conclusions suggest that wallowing is vital for the animals' well-being. The study is published in the journal Applied Animal Behaviour Science. It is already well accepted that pigs use wallows to keep cool. The animals do not have normal sweat glands, so they are unable, otherwise, to regulate their body temperature. The scientist who carried out the study, Marc Bracke from Wageningen University and Research Centre, trawled the scientific literature for evidence of what motivates other animals to carry out similar behaviours. He examined closely related "wallowers", including hippos, which spend their time in water to keep cool.