Evaluation of Manganese Ion on Controlling Harmful Microorganisms In vitro and In vivo for the Early-Weaned Pig

Two experiments were conducted to determine the effects of $MnSO_4$ on controlling harmful microorganisms in vitro and in vivo. The in vitro experiment was conducted to examine the effects of manganese sulfate $(MnSO_4)$ on the reduction of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) by growth stimulation of Pediococcus acidilactici (P. acidilactici; lactic acid bacteria). Manganese ion (0.003 %) was found to stimulate the growth of P. acidilactici in the In Vitro system. When E. coli and S. aureus were grown in a mixture with P. acidilactici, their numbers were reduced. This may be the result of a reduction of pH in the medium as a result of better growth of P. acidilactici due to stimulation by the Mn ion. The in vivo experiment was conducted to determine the effects of $MnSO_4$ in diets on controlling harmful microorganisms in fecal samples of pigs. There were no significant differences for the microbial numbers (i.e., total microorganisms, E. coli, lactic acid bacteria and S. aureus) in feces of pigs fed $MnSO_4$ compared to feces of pigs fed the control diet through 7 days. However, on day 7 of experiment, the pH of feces in pigs fed $MnSO_4$ (0.1%) decreased faster than pigs fed the control diet.