Effect of day to day variation of dietary energy on residual feed intake of laying hens.

An experiment was conducted that examined the effect of day-to-day variability of dietary energy on feed intake behavior. Three levels of average daily dietary ME composition (2,580, 2,814, and 3,009 kcal/kg) and three levels of day-to-day variability of ME (low, medium, and high) were assigned to nine groups of DeKalb-XL laying hens in a 3x3 factorial design. Each of the nine treatments contained 35 individually caged birds. Daily measurements of feed intake, egg production, and egg mass were taken for each bird in this 56-d experiment. Pre- and postexperiment body weights were taken at 23 and 31 wk of age. Increasing levels of day-to-day variance of ME were associated with increased feed consumption for each mean level of ME (P < 0.01) and increased variability of day-to-day feed intake for the 2,580 kcal/kg mean level (P < 0.01). No significant differences (P < 0.01) in egg production egg mass, or body weight were observed.