Effet chez le porcelet d'une exposition à un régime co-contaminé en ...

These are not the final page numbers8 B. Grenier et al. Mol. Nutr. Food Res. 2011, 55, 1–11Arbitrary UnitsArbitrary Units200015001000500050403020100Specific IgGSpecific IgAaa,breduced viability measured in human neutrophils exposedin vitro to this toxin [31]. For blood biochemistry, there was adecrease in albumin concentration in DON-exposed animalsand an increase in creatinin concentration in FB-exposedpiglets in accordance with previously published studies[18, 20, 32, 33]. Ingestion of diets co-contaminated withDON and FB had less effect on hematology and biochemistryparameters than did mono-contaminated diets. Somestudies have already reported a weaker effect on plasmabiochemical parameters for piglets fed multi-contaminateddiets than for piglets receiving mono-contaminated feeds[18, 19], which suggests an opposite effect of the twomycotoxins.Despite the absence of effects on zootechnical, hematologicaland biochemical parameters, ingestion of feedscontaminated with low concentrations of either DON or FBinduced histopathological lesions in liver, lungs andkidneys. Toxic effects of FB on liver have been reported inseveral papers using highly contaminated materials [9, 28].The effects included a disorganization of hepatic cords,hepatocellular vacuolation, megalocytosis, apoptosis,a1 7 14 21 28 35Length of exposure (days)Figure 2. Individual and combined effects of DON and FB onplasma concentrations of specific immunoglobulin (IgA and IgG)anti-OVA. Pigs received a control diet (J), or a DON-contaminateddiet ( ), or an FB-contaminated diet ( ) or a contaminateddiet with both toxins (K). At days 4 and 16 of the trial,animals receiving either control or contaminated feeds weresubcutaneously immunized with OVA. Plasma samples werecollected weekly and the levels of IgA and IgG specific for OVAwere determined by ELISA and normalized against a standardizedreference plasma. Values are mean7SEM for five animals.Statistics are mentioned when significant changes wereobserved.& 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheimbaa,bbbba,ba,baaa,bbbbaaaaa,bb,ccbaaaLymphocytes proliferative index654310Ovalbumin stimulation2 b1 7 14 21 28 35Length of exposure (days)Figure 3. Individual and combined effects of DON and FB onlymphocyte-specific (OVA) proliferation. Pigs received a controldiet (J), or a DON-contaminated diet ( ), or an FB-contaminateddiet ( ) or a contaminated diet with both toxins (K). At days 4and 16 of the trial, animals were subcutaneously immunizedwith OVA. Blood samples were taken weekly to measure thelymphocyte proliferation. Results are expressed as stimulatingindex of lymphocyte proliferation calculated as counts perminute in stimulated culture/cpm in control non-stimulatedculture. Values are mean7SEM for five animals. Statistics arementioned when significant changes were observed.necrosis and cell proliferation. In the present study, it wasobserved that even when present at a lower dose, FBinduced similar liver histopathological lesions. Liverlesions, such as hepatic cell vacuolation, were alsoobserved in piglets fed the DON-contaminated diet [34].These lesions were not associated with major biochemicalalterations. The biological meaning of the hepatic lesionsremains to be determined. Histopathological analysis oflung confirmed that this is a target organ for FB. At highdoses (Z92 mg/kg of feed for 4–7 days), FB induce lethalpulmonary edema in swine [9]. In the present study, the lowdose of FB also induced pulmonary damages, mainly BALTdepletion and vascular disorders. By contrast, when presentat a low dose in the diet, DON did not induce any lesion inthe lung.For the three organs investigated, the damages elicitedfrom the ingestion of the diet co-contaminated with DONand FB were equal to or higher than the ones elicited by theingestion of a single mycotoxin. Very few publicationsanalyzed the effects of mixed mycotoxins on histopathologicalparameters, especially at low doses [35, 36]. Thehistopathological lesions observed in the lungs ofco-exposed piglets were slightly more pronounced than theones observed in the lungs of FB-exposed animals. In theliver, ingestion of the co-contaminated diet induced significantlyhigher lesions than ingestion of either of the monocontaminatedfeeds as demonstrated by the lesion score andthe hepatocyte proliferation. One explanation for the highliver toxicity of DON and FB when present simultaneouslycould be the higher absorption of FB in the presence ofDON. Indeed, DON has recently been shown to decrease thebarrier function of the intestine [37]. Thus, ingestion ofabbwww.mnf-journal.comab b b