The current study was conducted in Baghdad governorate (Karkh and Al-Rasafa regions) which included collecting 50 samples of freshly slaughtered sheep meat randomly collected from local slaughter areas and approved governmental slaughterhouses (25 liver and 25 ulna muscles). The results of the aflatoxin B1 detection showed that all samples were contaminated with this toxin at different concentrations ranging from 25–422 ppb and 65–492 ppb for each ulna muscles and liver, respectively. The histopathological and immunological study was conducted in meat samples containing higher and lower concentrations of the toxin. The results of the pathological study in the liver revealed that the concentration (492 ppb) caused thickening of the nuclei, water degeneration and necrosis, but the concentration (467 ppb) caused several damages represented by thickening of the nuclei and an increase in the number of kepffer cells. In contrast, no obvious damages was observed at the concentration (65 ppb). In the muscles, the results showed that the concentrations (422 and 384 ppb) caused tissue damage represented by the homogeneous acid aggregation, while no damage was found at the concentration 25 ppb. The findings of the immunohistochemical study showed the same concentrations for both liver and muscle samples using CD marker of TNF-α; in the liver, at the concentration (492 ppb), there was strong immune expression (+++), while the immune expression was (++) at the concentration (467 ppb), and no expression (-) was detected at the concentration (65 ppb). In addition, the results in the muscles samples showed that samples that contain (422 ppb), the immune expression was (+++), while the expression at the concentration (384 ppb) was (++), whereas no expression was seen at the concentration (25 ppb).
