Effects of a Living Nonfreeze-Dried Lactobacillus acidophilus Culture on Performance, Egg Quality, and Gut Microflora in Commercial Layers ,

A living Lactobacillus acidophilus culture was incorporated into the diets of two commercial strains of laying hens at three geographical locations to study its effect on performance, egg quality, egg weight, and alterations in gut microflora. The Lactobacillus culture was added at the rate of .0125, .0375, or .0625% of the diet. Feeding the Lactobacillus resulted in significantly increased egg production at one location (Arizona), a numerical improvement at the second (Florida), and no difference at die third location (South Dakota). An across-trial analysis of all egg production data provided a statistical advantage to adding Lactobacillus to diets of commercial layers. One location (Arizona) reported a significant response in feed efficiency (kg/doz eggs) at lower Lactobacillus levels. The other locations were unable to statistically demonstrate a similar response. The addition of Lactobacillus did not alter egg quality or egg weights. At two locations, Lactobacillus treated hens consumed more feed than nontreated hens during warmer months. An early increase in Lactobacillus acidophilus organisms accompanied by a drastic reduction in coliforms in selected gastrointestinal sections was measured in one study (Florida). A later measurement of the microflora did not substantiate this observation.