LAUSR

Enriched environment can promote the adaptability of animals to cope with the complex environments. To evaluate how enriched environment experience can help laying hens resist to transport stress, a total of 432 18-week-old laying hens were randomly divided into two treated groups of which one group was housed in conventional battery cages (CC, 24 replicate cages, 3 birds/cage) and the other was in furnished cages (FC, 24 repeated cages, 15 birds/cage). At their 64 weeks of age, one hen per replicate was selected for 4h transportation. The spleen of hens was collected before transportation, after the transportation and 48h for recovery. The expression of heat shock proteins (HSPs), heat shock factors (HSFs) and inflammatory factors were measured. The serum from those birds was collected to detect inflammatory cytokines levels. Variance analysis showed that the expression of most of the detected HSPs and HSFs indicators were decreased after transportation and then elevated later. The mRNA expression of HSP10, 40, 60, 70, 90 and 110, HSF2 and HSF3 and the protein expression of HSP 60, 70 and 90 were higher in FC group than CC after the transportation and recovery (P < 0.05). Moreover, the hens housed in FC group had the lower mRNA expression of pro-inflammatory factors of nuclear transcription factor (NF-κB), cyclooxygenase-2 (COX-2) and prostaglandin E synthase (PTGEs) before and after the transportation compared to CC group (P < 0.05). The mRNA expression of inflammatory cytokines of interleukin-2 (IL-2), -6 (IL-6) and tumor necrosis factor (TNF-α) and serum concentration of IL-1β and TNF-α in FC hens were lower than CC after the transportation (P < 0.05), respectively. Therefore, by regulating the heat shock protective response and inflammatory cytokines expression, the enriched environment can reduce the stress damage of laying hens and improve the resistance to transport stress.