Some Effects of Cage and Floor Rearing on Commercial White Leghorn Pullets During Growth and the First Year of Egg Production

Abstract

Cage and floor-pen rearing effects on body weights and livability of pullets of three White Leghorn commercial strains were compared during the rearing period. When variances of body weights were compared within strains at eight ages, greater variability was detected in 4 of 24 comparisons for caged pullets and in 3 of 24 comparisons for floor-pen pullets. Pullets reared in cages were heavier at 5, 11, and 19 wk of age. Livability scores did not differ for pullets in the two rearing environments. Differences in body weight, present among the three genetic stocks at most ages during the rearing period, diminished with age and were no longer present at 19 wk. No genetic stock × rearing environment interactions were evident for body weights during the rearing period.Carry-over effects from cage and floor pen rearing into the laying period were small and transient; pullets reared in cages attained sexual maturity .2 wk earlier and had 6% higher hen-housed egg production for the first 4-wk period. However, when compared for the full 48-wk laying period, no significant differences associated with rearing environments were found for livability, rate of lay, hen-housed egg production, egg weight, or egg mass. Although 32 g heavier when housed at 19 wk, cage-reared hens did not differ significantly in body weight from floor-pen reared hens at 20, 50, and 67 wk. Hens reared in cages had better feather scores at 60 to 63 wk of age, but no difference was evident at 75 to 78 wk. Although differences among the genetic stocks were present for productivity traits, nervousness, and feather coverage, genetic stock × rearing environment interactions were generally absent during the laying period.