The Fusarium mycotoxins deoxynivalenol (DON) and zearalenone (ZEA) frequently contaminate
grain crops, especially maize, the basis of poultry's feed. Mycotoxins enter the food
chain and induce pathological changes in edible tissues. Milk thistle (Silybum marianum)
has been used for the treatment of liver disease in humans because of its antioxidant
and hepatoprotective effects, but its utility in veterinary use is poorly examined.
To investigate possible protective properties against mycotoxin caused oxidative stress
in poultry, pressed form of milk thistle seed (0.5%) was tested in white, female,
Hungarian ducks over a feeding period of 47 days. Ducks were separated into 3 groups.
The first group was fed with normal diet. The second group was fed with normal diet
contaminated with DON (4.9 mg/kg) and ZEA (0.66 mg/kg). The third group received mycotoxin
contaminated feed with milk thistle supplementation. Histological examination, markers
of the redox status and metal element concentration measurements were carried out.
The results showed alterations in the histological examination and in the redox homeostasis
markers as a short-term effect by strengthening the antioxidant system. Acute exposure
of mycotoxins caused an oxidative stress, which induced an effective antioxidant defensive
response of the organism indicated by the free sulfhydryl group content (from 0.72
± 0.06 to 0.77 ± 0.11) and the reducing power (0.49 ± 0.06 to 0.52 ± 0.08) elevation.
The short-term free radical injury may be compensated by the liver resulting in decreased
lipid peroxidation markers (malondialdehyde concentration: from 16.86 ± 0.49 to 0.94
± 0.15, conjugated diene concentration: from 0.21 ± 0.07 to 0.17 ± 0.03). Silymarin
further strengthtened the antioxidant defense by the elevation of sulfhydryl groups
concentration and reducing power property resulted in decreased total scavenger capacity.
However the concentration of lipid peroxidation markers were further elevated by the
used antioxidant treatment (MDA: 5.2 ± 0.35, DC: 0.26 ± 0.08). In conclusion, the
mycotoxin-contamination activated effectively the antioxidant system. The milk thistle
supplementation has cytoprotective effects according to the histological findings,
activated the antioxidant system, however the elevation of lipid peroxidation products
need further explanation.
