['Zearalenone (ZEN) is an estrogenic mycotoxin produced by numerous Fusarium species in pre- or post-harvest cereals. ZEN displays a potent estrogenicity in livestock and also causes severe immunological problems. The aims of this study were to isolate a new ZEN-degrading micro-organism for biological detoxification, to examine its ability to degrade ZEN in liquid medium, and to evaluate its potential for in vivo preventitive effects against ZEN (as would occur with contaminated feed)-induced immunomodulation in mice.', 'Lactobacillus paracasei BEJ01 (LP) isolated from Tunisian artisanal butter was found to display significant binding ability to ZEN in phosphate-buffered saline (i.e. 96.6%) within 24 h of incubation. The in vivo study was conducted using Balb/c mice that received either vehicle (control), LP only (at 2\u2009×\u200910(9\u2009)cfu/l, ∼2 mg/kg BW), ZEN alone (at 40 mg/kg BW), or ZEN\u2009+\u2009LP daily for 15 d.', 'Compared to control mice, ZEN treatment led to significantly decreased body weight gains and decrements in all immune parameters assessed. The addition of LP to ZEN strongly reduced the adverse effects of ZEN on each parameter. In fact, mice receiving ZEN\u2009+\u2009LP co-treatment displayed no significant differences in the assayed parameters as compared to the control mice. The exposures to the bacteria alone had no adverse effects in the mice.'] Does lactobacillus paracasei BEJ01 prevent immunotoxic effects during chronic zearalenone exposure in Balb/c mice?