Sex-related differences in the immune response of weanling piglets exposed to low doses of fumonisin extract

Abstract

Fumonisin B 1 (FB 1 ) is a mycotoxin produced by Fusarium verticillioides , a fungus that commonly contaminates maize. Sex-related effects of FB 1 have been observed with respect to carcinogenicity in rodents, to performances in pigs and immunosuppression in mice. In the present study the sex-related effect of FB 1 on the pig immune response was determined. Female and castrated male piglets received for 28d either control feed or feed contaminated with 8mg FB 1 /kgfeed in the form of F. verticillioides culture material. At day 7 and day 21, animals were immunised subcutaneously with a Mycoplasma agalactiae vaccine. Ingestion of FB 1 -contaminated feed significantly decreased weight gain in males but had no effect in females. No sex-related difference was observed in biochemical parameters, but a higher level of creatinine was noted in toxin-treated animals. FB 1 also altered the pig immune response in a sex-specific manner. In males, ingestion of FB 1 -contaminated feed significantly decreased specific antibody levels after vaccination as well as the mRNA expression level of IL-10. In females, the toxin has no effect on specific antibodies or on cytokine mRNA levels. The results of the present study indicatethat FB 1 is immunosuppressive in pigs. The magnitude of this FB 1 -induced immunosuppression is highly dependent on sex, with males being more susceptible than females.