Producers are being advised to raise the set temperature on pig building control systems on hot days to reduce temperature fluctuations, especially in finishing sheds.
According to ARM Buildings’ environmental specialist, Tim Miller, many producers believe that their controllers are not working because they have set the temperature at 18 degrees centigrade (18C), but the thermometer goes up to over 30C. When he advises turning the setting up on hot days, however, the most common response is “surely you want to turn it down”.
The answer is to do quite the opposite.
“If the setting is left at 18C when the air outside the building cools in the evening, the temperature inside the piggery drops rapidly and this is not good for the pigs,” he said, adding that he’d seen temperatures inside buildings changing by 14 degrees within about six hours, going from hot to cold, then cold to hot the next day.
“By raising the set temperature these fluctuations are reduced and the pigs are more able to acclimatise. In fact, we’ve been getting some issues with pigs suffering from cold draughts during the big swings in temperatures.”
Mr Miller (pictured above) also pointed out that no-matter how good the controls and ventilation system may be, it is impossible to get the temperature below that of the ambient level outside, without air-conditioning or a cooling facility. “By raising the set temperature it is possible to mitigate the violent swings and this can help reduce heat stress,” he said, adding that, depending on conditions, the advice for finishers is to set the temperature on the controller to around 22C on hot days.
He also said that while he’d found that some ACNV systems have done well, that didn’t apply to those in sheltered spots where it is “more difficult” for the air to circulate.