Effect of native Lactobacillus murinus LbP2 administration on total fecal IgA in healthy dogs

The objective of the present work was to determine the effect of Lactobacillus murinus strain LbP2 on canine fecal immunoglobulin A (IgA) levels. Seven dogs were orally treated with a 3-mL suspension of L. murinus LbP2 containing 5 × 10⁹ colony-forming units on alternate days for 2 wk. Six dogs were treated with 3 mL of phosphate-buffered saline as placebo. Fecal samples were taken from the rectal ampulla on days 0 and 16, and the total canine fecal IgA concentration was determined with an immunoperoxidase assay kit. The IgA levels of individual dogs were compared with the nonparametric Wilcoxon test. Differences were considered significant when the P-value was less than 0.05. An increase in the total fecal IgA concentration was observed in the 7 dogs after treatment with L. murinus LbP2 (P = 0.01796). No differences were detected between the initial total fecal IgA values and those obtained at the end of placebo treatment. Thus, after oral administration L. murinus LbP2 showed potential immunomodulatory effects, an important property to assess in a microorganism being considered for use as a probiotic.