Efficacy of a mannan oligosaccharide (Bio-Mos®) for improving nursery pig performance

Objectives: To analyze all known available data to determine whether a mannan oligosaccharide (Bio-Mos; Alltech, Inc, Nicholasville, Kentucky), provided as a feed additive, improves the growth performance of nursery pigs, and what production factors influence the existence or size of that response. Materials and methods: A combined analysis (meta-analysis) was performed using all available, relevant data in a data set based on published and unpublished data. A total of 54 comparisons were made (pigs fed Bio-Mos or no Bio-Mos). The response to Bio-Mos throughout the experimental period was examined with either one or several independent variables in the model. Independent variables included weaning age, length of experiment, dietary Bio-Mos inclusion level, publication status, growth performance during the first nursery stage, antimicrobials in the diet, site of the experiment, and complexity of the first-stage diet. Analysis of variance was used to detect differences in the performance response to Bio-Mos between levels of a variable. Results: Overall, performance was better in pigs fed Bio-Mos than in the controls. The data indicate that pigs with a slow growth rate during the first 1 to 2 weeks postweaning have a more pronounced response to Bio-Mos than do pigs with a normal or accelerated growth rate. Dietary inclusion of Bio-Mos appears to be most effective immediately after weaning, but a smaller response may persist for several weeks. Implications: On the basis of this comprehensive analysis of all known available data, we conclude that Bio-Mos has potential as an acceptable growth promoter for nursery pigs.