Feedlot Performance of Lambs Fed Lactic Acid-Producing Bacteria

Abstract

A total of 1399 feeder lambs were assembled and transported under normal industry conditions and used in three experiments over a 18-mo period to determine the effect of feeding lactic acid-producing bacteria (LAB) during the first 3 to 5 d of adaptation to the feedlot environment on dry matter intake, gain, and feed efficiency. The LAB was added as a topdress to the daily diet in Exp. 1 and mixed with the total diet in Exp. 2 and 3. Each lamb consumed 5 to 5.7 g/d of inoculant containing 10 million LAB per gram. Adding LAB to the diet of feeder lambs did not consistently increase the performance of the lambs compared to the control group. When lambs were placed in the feedlot shortly after arrival (Exp. 1), those fed LAB gained more weight (P<.10) and were more efficient (P<.10) than lambs not fed LAB. If lambs were allowed to recover from stress of assembly and transit for a minimum of 60 d before entering the feedlot, response to LAB was not as dramatic as observed in Exp. 1. The magnitude of change in performance of feeder lambs to the addition of a viable LAB appears to be dependent upon the amount of external stress. Under stressful conditions addition of LAB to the diet of lambs may Increase rate and efficiency of gain.