Colder weather could be a blessing for pig farmers with naturally-ventilated straw-based finishing houses. On some farms there has been an endless round of mucking out dirty bedding because the pigs’ dunging habits have been reversed.
Tim Miller, environmental specialist with ARM Building, has been called out on numerous occasions to advise on ventilation throughout the run of hot weather during summer and autumn because pigs have been lying in the wetter, solid dunging passages to keep cool, then dung in the hotter, dry bedded area.
“Straw is a requirement for high-welfare contracts. While this is good for the image of the pig industry, it is ironic that during the summer this is less welfare friendly and dirty pigs do not make a good impression,” he commented. “This is not often a problem with slatted buildings.”
He feels there needs to be more research into this area. “A number of farms have installed powered ventilation systems in an effort to improve the lying pattern but, in my experience, this has not been particularly successful. It may be that the use of less bedding in the summer, allowing pigs to lie on the cooler concrete, would help but this may not be viewed favourably with the inspectors,” he said. “It only takes one pig to dung in the wrong place for the problem to start.”
One solution that has worked on some farms has been the use of low-volume ventilation through polythene tubes, suspended over the lying area. These direct a gentle, but cooling draught down on the pigs so that they can lie and sleep in comfort. They are relatively inexpensive, can be adapted to most layouts and are normally operated by a single fan per tube.
“With the drive to more welfare-friendly systems and the growth in purpose-built straw-based system houses, this is not an issue that will go away,” declared Tim. “There is nothing more demoralising for a stockperson than a back-breaking daily routine of manually scraping out a dirty bed, so more work needs to be done on factors influencing dunging patterns on straw-based buildings to allow pigs to remain clean.”