Tethered versus loose sows: ethological observations and measures of productivity. I. Ethological observations during pregnancy and farrowing.
Ethological parameters were recorded from sows housed in the same room and allocated to four experimental groups: sows that were tethered during pregnancy as well as from one week before farrowing to 8 weeks after; sows that were tethered during pregnancy but were loose during farrowing and lactation; sows that were loose during pregnancy in social groups of 2-5 animals and tethered during farrowing and lactation, and sows that were loose during pregnancy as in group 3 and also loose during farrowing and lactation. By using a timelapse-film technique it was found that pregnant sows in all groups had a similar diurnal rhythm with peaks around feeding times. The animals lay down for 20 h or more per day, and their activity was reduced due to tethering during the pregnancy period itself and due to preceding periods of tethering during farrowing and lactation. With increasing environmental temperature the loose sows increased the time spent lying on the side at the expense of lying on the belly. The tethered sows, however, showed no such change, but contrary to the loose sows they increased their activity. Observations around feeding time revealed that the tethered sows showed more aggression and fewer non aggressive social elements than the loose sows. Additionally their eating time was longer. Rubbing the neck was less and lying unquietly more frequent in tethered sows. Finally tethering during pregnancy reduced exploration directed towards straw and floor and increased stereotyped bar-biting and chain-nippling. With increasing temperature rubbing behaviour and drinking increased in tethered but not in loose sows. Timelapse-videorecording during the last 48 h prior to- and until the end of farrowing revealed that sows in all groups, no matter whether they were loose or tethered, showed a characteristical increase in nestbuilding activity until about 12-6 h before first piglet was born. Tethering in any period (pregnancy and/or farrowing-lactation) resulted in an increased farrowing time by approximately 100 min.
D000818:Animals; D001522:Behavior, Animal; D004326:Drinking; D004435:Eating; D005260:Female; D007743:Labor, Obstetric; D009043:Motor Activity; D011187:Posture; D011247:Pregnancy; D011270:Pregnancy, Animal; D012149:Restraint, Physical / Q000662:veterinary*; D012919:Social Behavior; D013552:Swine / Q000502:physiology*