Rearing piglets in a poor environment: developmental aspects of social stress in pigs.

Autor: De Jonge FH; Department of Animal Husbandry, Agricultural University, Wageningen, The Netherlands. Francien.deJonge@etho.vh.wau.nl, Bokkers EA, Schouten WG, Helmond FA
Jazyk: angličtina
Zdroj: Physiology & behavior [Physiol Behav] 1996 Aug; Vol. 60 (2), pp. 389-96.
DOI: 10.1016/0031-9384(96)00013-3
Abstrakt: Effects of rearing conditions on the development of social relationships were investigated in female pigs. For that purpose, one group of piglets was reared in a poor environment (i.e., a commercially used indoor 4.2-m2 standard farrowing crate) and the other in an enriched environment (i.e., 0.5-ha outdoor pasture with half-open farrowing crates). After weaning, all piglets were housed in pairs under standard conditions. Dominant and subordinate individuals were distinguished within pairs and social relationships between members of a pair were studied in adulthood. The results show that pairs reared in a poor environment behave more aggressively. The subordinates of these pairs also develop symptoms indicative of chronic social stress exposure: i.e., they show a delayed onset of puberty, a smaller daily weight gain, and elevated basal cortisol levels that are also higher 5 h after an acute restraint stressor (tethering stress). No such deviations were found in subordinates reared in an enriched environment. It is concluded that rearing piglets in a poor environment may facilitate the development of social stress in adult (subordinate) pigs. Two underlying mechanisms may be proposed: a) deteriorated social skills lead to increased social stress, or b) a failure to cope with stressors in general, and the stress of being subordinate in particular, occurs in animals reared under poor conditions.
Databáze: MEDLINE