Efficacy of dietary Bacillus subtilis and Bacillus licheniformis supplementation continuously in pullet and lay period on egg production, excreta microflora, and egg quality of Hyline-Brown birds.

The aim of the present study was to evaluate the efficacy of Bacillus-based probiotic in pullet to lay period. A total of 12-wk-old 384 Hy-line Brown pullets (initial BW of 1.05 kg, 8 replications; 16 birds per replication pen) were used in a 6-wk feeding trial. Birds were blocked based on BW and randomly allotted to 1 of 3 dietary treatments that consisted of basal diet as CON; GPM, basal diet+ (GalliPro Max/B. subtilis, 500 g/ton); GPT, basal diet+ (GalliPro Tect/B. licheniformis, 500 g/ton). During the pullet stage, birds that were fed CON diet and CON diet supplemented with either 500 g/ton B. sublitis or B. licheniformis were randomly assigned to 1 of 7 treatments with 9 replications (6 birds per replication) during lay period. For this, a total of 162 birds fed CON diets were randomly chosen and subdivided into 3 groups and fed CON, GPM, and GPT diets. From the birds that were fed either GPM or GPT diet at pullet phase, about 108 birds from each treatment were randomly chosen and were subdivided into 2 treatments and fed either GPM or GPT diet. The feed intake was higher (P < 0.05) in GPT treatment and lower (P < 0.05) in GPM treatment compared with CON during the pullet period. In addition, the excreta Escherichia coli counts were reduced (P < 0.05) in pullets fed GPT diet. The egg production rate significantly increased (P < 0.05) for layers fed GPM diet and a slight increase was also seen for GPT treatment birds compared with CON during week 32. During the lay period, the average mean values for albumen height and yolk color at week 25 to 45 were higher (P < 0.05) for GPM fed birds compared with those fed GPT and CON diets. In conclusion, Bacillus-based probiotic supplementation in the diet conferred some positive effects during pullet to lay period.