SUCKLING BEHAVIOR OF SOWS IN FARROWING CRATES AND STRAW-BEDDED PENS

The behaviour of 18 primiparous Large White (LW) or LW X Duroc sows and their litters was observed during 6 days in lactation ( 1, 2, 3, 7, 14 and 21 ) in two housing treatments: (1) farrowing crate (1.6 m X 2.2 m) without straw; (2) farrowing pen (2.8 m X 2.8 m) with straw added. After farrowing, litter size was standardized to nine or ten piglets. Sows in crates spent less (P < 0.01 ) time performing rapid suckling grunts between 09:00 and 13:00 h on observation days, and had shorter (P < 0.001 ) bouts of this behaviour than sows in pens with straw. Litters in the crate treatment spent less (P < 0.03) time performing rapid sucking movements (drinking) and displayed shorter (P < 0.01) bouts of drinking than litters in pens with straw. Piglet location within the pen/crate was affected by treatment: litters in crates, particularly on the first day of lactation, spent more time (P < 0.01 ) in the heated creep area and less (P < 0.01 ) time in the open away from the creep area, and away from the close proximity of the sow, than litters in the pen treatment. The observed increase in rapid sucking movements (drinking) by litters in the pen treatment did not result in an increased weight gain by piglets. It was concluded that the (apparent) increase in milk intake was not partitioned to growth, but may have been used by piglets to maintain body temperature with the increased time piglets spent away from the creep and the sow in the pen treatment.