Assessment of the efficacy and modulation of the immune response of the inactivated strain Enterococcus faecalis CECT7121 in diarrhea foals

Abstract

The immune system of foals is a continuous challenge from birth. Up to 60% of foals developing diarrhea in the first months of life. The secretory immunoglobulin A (IgA) plays the role of antibody in mucosal adaptive immunity. Some benefic live bacteria exert a general immune stimulation making control against pathogens. The main goal of this study was to assess the efficacy of inactivated benefic strain Enterococcus faecalis CECT7121 on the immune response in the gastrointestinal tract of newborn foals. This study was designed in an observational, prospective, crossover design, taken the concentrations of Ig A obtained from the saliva, as surrogate marker of the intestinal IgA concentrations. Thirty seven foals were divided in two groups. Animals of the control group I (n=22) received the placebo formulation (distilled water) by oral route. The experimental Group II (n=15), were orally treated with a formulation containing the inactivated E. faecalis CECT7121 in a concentration of 1 x109 UFC. Both treatments were carried out throughout 6 days. The presence and duration of diarrhea was recording for animals of each group. Representative saliva samples were taken in whole foals by swabbing. The technique used for determining the IgA concentrations was the Quantitative Radial Immunodiffusion. The Ig A concentrations was assessed as Areas Under the concentration vs. time Curve (AUC). The AUC values obtained for the control group (46.34 ± 2.8 mg/dL) was significantly (p value <0.0001) lower than that obtained for the experimental group (76.34 ± 4.9 mg/dL). Those values of Ig A obtained for the experimental group correlated with decrease of diarrhea in 35 % . In conclusion, the higher IgA values found in saliva after given the formulation with inactivated bacteria in animals of the experimental group, correlated with a relevant immunomodulatory activity with diarrhea decrease.