Olsson I A, de Jonge F H, Schuurman T, Helmond F A
Department of Animal Environment and Health, Swedish University of Agricultural Sciences, P.O. Box 234, 532 23 Skara, Sweden.
Department of Ecological Agriculture, Wageningen Agricultural University, Haarweg 333, 6709 RZ Wageningen, The Netherlands.
Behav Processes. 1999 Jul;46(3):201-15. doi: 10.1016/s0376-6357(99)00036-4.
Effects of rearing condition on behavioural and physiological reaction to social confrontations and to social and non-social stressors were studied in female pigs. The pigs were reared under either poor (the standard farrowing crate) or enriched (group of free-ranging sows with piglets) conditions. At the age of 14-17 weeks, the pigs were exposed to a series of social confrontations where an intruder was introduced into the home pen of a resident. The results show the presence of a clear difference in terms of aggressive behaviour between residents and intruders from enriched but not from poor rearing conditions. Furthermore pigs reared under poor conditions inflicted more wounds on each other. We suggest that this reflects a difficulty in establishing a dominance relationship in poorly reared pigs, caused by impaired development of social skills in these pigs. Subsequently, reaction to novel object, non-social and social stress was measured in adult age, showing that the effects of rearing conditions are long-lasting, and give rise to differences in reaction to challenges in that pigs from enriched rearing conditions showed more avoidance behaviour than pigs from poor rearing conditions.
研究了饲养条件对母猪社交对抗以及社交和非社交应激源的行为和生理反应的影响。这些母猪分别饲养在恶劣条件下（标准产仔箱）或丰富环境中（自由放养的母猪与仔猪群体）。在14至17周龄时，让这些母猪经历一系列社交对抗，即向一只常住母猪的圈舍中引入一只入侵者。结果显示，来自丰富环境而非恶劣饲养条件下的常住母猪和入侵者在攻击行为方面存在明显差异。此外，在恶劣条件下饲养的母猪相互造成的伤口更多。我们认为，这反映了饲养条件差的母猪在建立优势关系方面存在困难，这是由于这些母猪社交技能发育受损所致。随后，在成年期测量了对新物体、非社交和社交应激的反应，结果表明饲养条件的影响是持久的，并且导致了对挑战的反应差异，即来自丰富饲养条件的母猪比来自恶劣饲养条件的母猪表现出更多的回避行为。
