During the current heatwave farmers need to be realistic about their piggery ventilation management says an environmental specialist.

Tim Miller or ARM Buildings said: “Without a cooling system it is impossible to lower temperatures below the ambient. If the outside temperature is over 30 deg C then it is unrealistic to set the dial to 21 deg C and expect this temperature to be reached, however hard the fans work.

“Worse still, this means that the temperature will drop too rapidly on cool nights which may upset the pigs. They don’t appreciate big swings in temperature.”

He says that, whereas in winter the temperature for finishers can be set at 18 deg C, for summer farmers should adjust the thermostat to 23 deg C, which will mean the building is well ventilated without the rapid swings in temperature.

Emergency ventilation system and alarm systems need to be working and the alarm system set at a sensible level to avoid false-alarms. Pig farmers should then check fans, shutters baffles and inlets to ensure they are clean and operating properly.

Mr Miller said: “We have found that ventilation monitoring has been an invaluable tool in hot weather. If a piggery has six rooms and one has abnormal temperatures, then this suggests a problem."