Environmental Factors Affecting the Egg Laying Habits of White Leghorns

Two experiments were conducted using White Leghorns to study floor egg laying habits of pullets reared on the range and in confinement. In Experiment 1, 120 pullets were reared in enclosed pens. At 16 weeks, 60 of these pullets were placed on range for 5 weeks. Percentages of eggs laid on the floor from 28 to 36 weeks were 9.7 for pullets reared in enclosed pens and .8 for pullets reared on range. In Experiment 2, 240 pullets were reared in an open-front house and allowed to enter covered outside areas at 4 weeks. Three treatments of 80 pullets were formed. One treatment group was placed in enclosed pens at 16 weeks, pullets in the second treatment remained in the open-front house to 20 weeks, and the third treatment group was placed on range at 16 weeks for 4 weeks. Percentages of floor eggs laid from 20 to 36 weeks were 11.4 for enclosed pens, 4.5 for open-front house, and .8 for range. In both experiments, significant differences were found between treat­ ments. No significant differences from 28 to 36 weeks of age were obtained for performance mea­ surements among treatments. Results indicated that placing pullets on range for 4 to 5 weeks or in an open-front house with covered outside areas stimulates them to use nests. (Key words: pullets, floor eggs, range, confinement) 1986 Poultry Science 65:693-695