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

INTRODUCTIONCellular oxidative stress was also proposed as a possible mechanism of cancer initiation. However,Theumer et al. (2010) only observed a less than additive and an antagonistic interaction between thetwo toxins when looking at DNA lesions using the alkaline comet assay (ACA) and the micronucleustechnique (MN), respectively (Table 1). Furthermore, in the same study, a less than additiveinteraction was recorded in the MDA and CAT activity, both are being biomarkers of oxidative stress.f) effects AF and FB on immunityFew studies investigated the combined effect of AF and FB on immunity (Table 1). After ingestionof the co-contaminated diet, the interaction on the reduced lymphocytes proliferation uponmitogenic stimulation, was described either as less than additive (Kubena et al., 1995b) or additive(Harvey et al., 1995b). Tessari et al. (2006) showed a synergistic decrease of the antibodies titersagainst Newcastle Disease. By contrast, Weibking et al. (1994) reported an unexpected increase andan additive effect of the two toxins when looking at the hemagglutination titers against SRBC inturkey poults.2) Interaction between Aflatoxins (AF) and Ochratoxin A (OTA)a) effects of AF and OTA on zootechnical parametersAs indicated in Table 2, the interaction between AF and OTA on animal performance has beenstudied in 11 publications. In most of these studies, the association induced a synergistic or anadditive effect on body weight gain (Harvey et al., 1989a; Huff and Doerr, 1981; Huff et al., 1983;Huff et al., 1992; Sakhare et al., 2007; Verma et al., 2004). In addition, Huff et al. (1983) observedthat even four weeks after exposure to the co-contaminated diet had stopped, the animals did notrecover their normal body weight. The same author also observed that in chicken, ingestion of feedco-contaminated with AF and OTA decreased carcass yield, breast weight and other processingparameters in a synergistic manner (Huff et al., 1984) (Table 2).Both AF and OTA affect egg production and hatchability, and one group investigated thecombined effect of these two toxins on laying hens (Verma et al., 2003; 2007) (Table 2). An additiveinteraction of AF and OTA was observed on egg production and on the feed efficiency (consumptionfor egg production) (Verma et al., 2003). Regarding egg quality, less than additive and antagonisticinteractions were observed on egg. Protein and energy utilization were also modulated by theconsumption of AF and OTA. However the interaction between the two toxins varied according totheir concentrations ranging from synergistic to less than additive effect (Verma et al., 2007).27