Comparative effects of furnished and battery cages on egg production and physiological parameters in White Leghorn hens.

Laboratory animal well-being can be improved by housing the animals in species-specific natural or near-to-natural environments. An enriched environment may have a similar effect on chickens. The purpose of this study was to examine if housing environment (furnished cages vs. battery cages) effects the well-being of laying hens. One hundred ninety-two 1-d-old non-beak-trimmed White Leghorn W-36 chicks were reared and randomly assigned into battery cages or furnished cages at 19 wk of age. The furnished cages had wire floors and solid metal walls, with perches, a dustbathing area, scratch pads, and a nestbox area with concealment curtain. Ten hens were housed per cage, providing a stocking density of 610 cm2 of floor space per hen. The battery cages were commercial wire cages containing 6 birds per cage, providing 645 cm2 of floor space per hen. Body weight and egg production were calculated from 25 to 60 wk of age. The peripheral concentrations of dopamine, epinephrine, norepinephrine, serotonin, corticosterone, and IgG were analyzed at 30, 40, 50, and 60 wk of age. Compared with the hens housed in the battery cages, the hens housed in the furnished cages were significantly heavier from 30 to 60 wk of age (P<0.05 and 0.01, respectively) and produced more eggs at 40 wk of age (P<0.05). There were no treatment effects on eggshell thickness (P>0.05). The concentrations of serotonin were reduced, whereas corticosterone was increased from 50 to 60 wk of age in the hens housed in the battery cages (P<0.05) but not in those housed in the furnished cages, which may indicate that the hens housed in the battery cages were stressed. Although further studies remain to be completed, the present results suggest that furnished cages may be a favorable alternative for housing laying hens.