5 April 1996

Modified sow pens cut litter mortality

By Jonathan Riley

MODIFICATIONS to welfare friendly farrowing systems have reduced piglet mortality but rates are still unacceptably high.

University of Cambridge researcher Jeremy Marchant told delegates at a MAFF-sponsored health and welfare conference, at Market Bosworth, Leics, that previous studies had found sow welfare improved as she had freedom of movement and a choice of environments. But piglet mortality rates of 24% in community pens were recorded. Growth rates were also lower in pens (213g a day) than crates (252g a day).

Main cause of death was overlying and one of the causes was that sows often chose to lie outside the pen in the dunging area.

Working at ADAS Terrington on a MAFF-sponsored study, Dr Marchant modified community pens by providing sloping walls for the sow to lie against and moved creep boxes from the front to the rear of the pen. Solid walls up to 1m (3.3ft) high between adjacent pens were installed to try to give the sow more seclusion. All modifications were aimed at encouraging the sow to spend more time lying in the pen and reduce the risk to piglets as she laid down. "These recent modifications have to date reduced piglet mortality to 17.6% – still too high for commercial viability, although growth rates improved to 260g a day," said Dr Marchant.

"The system has also highlighted a wide difference in maternal behaviour between individual sows."

&#8226 Sow spends more time lying in the pen.

&#8226 Piglet mortality rates down from 24% to 17.6%.

&#8226 Piglet growth rates up from 213g to 260g a day.