Untersuchungen zum Futteraufnahmeverhalten ad libitum gefütter­ ter tragender Sauen in Gruppenhaltung an Rohrautomaten0

Abstract. Title of the paper: Investigations on feed intake behaviour of ad libitum fed group housed pregnant sows at tube feeders Investigations took place in 3 farms with group sizes of 8 to 32 sows and ad libitum feeding at tube feeders with energy reduced feed (9.3 to 9.6 MJ ME/kg) using unmolassed sugar beet chips (10 %), straw meal (25 %) resp in ration. Behavioural observations have been made with infrared video technique and time lapse video recording always during 24 hours. Individual duration of staying at trough in 24 hours and percentage of time feeding places were used by different number of sows per hour during 24 hours were analysed by QBSERVER/Video-Tape-Anatysis-System. Large individual differences in duration of staying at trough in 24 hours occurred between sows of a group with means from 1.8 to 18.0 % although all sows had free access to always available food. Behavioural investigations have shown that several sows did not come to trough over 24 hours without showing clinical signs of a disease At the same time this is a hint at the problem of disease control of ad lib fed sows especially in large groups Analysing the percentage of time feeding places were used by different number of sows a biphasic dynamics of feed intake behaviour of ad lib fed sows was found with a peak in the morning (7 to 10 a.m.) and a more distinct peak in the afternoon (3 to 7 p.m.).