Problems with overlying have been seen where these are set too hot and piglets choose not to lie on the mats, says Paul Thompson, veterinary consultant to pig-breeding company ACMC Ltd.

Watching the behaviour of piglets is crucial to setting the temperature correctly. Some common problems to check for are individual mat failures, mats with piglets of different ages being controlled by only one controller and the temperature sensor being positioned so that the mat is ‘trying to heat’ the farrowing house.

Relatively cheep infra-red thermometers, that allow the temperature of mats to be quickly assessed, are available.