The influence of 2 concentrations of yeast cell wall (YCW), supplied as Safmannan A, at 250 and 500 ppm on early production laying hen performance (21–36 wk) was investigated in this study. A total of 75 Lohmann W-36 replacement pullets, 17 wk old, were distributed among 75 laying hen cages (1 bird/pen). Three treatments were sequentially assigned to an equal number of pens per treatment. The 3 diets mixed were a basal diet only (control) and a basal diet supplemented with 250 or 500 ppm of Safmannan A (YCW 250 and YCW 500).

Feed and water were offered ad libitum. Data were collected for period 1 when birds were 21 wk old and hen day egg production was >90%. Treatment YCW 250 resulted in significantly higher egg weight from 21 to 28 wk old and higher than YCW 500 from 29 to 36 wk old. Treatment YCW 250 resulted in a calculated average cumulative liquid egg yield of 5.47 kg/bird over 4 production periods versus 5.29 kg/bird for the control and 5.13 kg/bird for YCW 500. Over the first production period, feed consumed per dozen eggs was significantly lower in treatment YCW 500 versus treatment YCW 250, but not significantly lower than the control treatment. Feed consumption per dozen eggs was not different among treatments for the remainder of the study.

Average feed consumed per bird per day and cumulative egg production at any point in time was not different between treatments. Specific gravity, egg shell thickness, egg shell weight, and percent shell weight were significantly higher in hens fed YCW 500 versus YCW 250 at 36 wk of age. Overall, feeding a diet supplemented with 250 ppm Safmannan A improved egg weight and liquid egg yield in early production laying hens, whereas shell quality was improved when feeding Safmannan A at the historically recommended concentration of 500 ppm.