GSTM1 and microcytic anemia: The results of our study showed that the Hb, HCT, MCV and MCH of Yudong black goats in the experimental pasture were very significantly reduced (p < 0.01), the significant decrease in Hb and HCT values indicated the presence of anemia indicators in Yudong black goats, and the significant decrease in MCV and MCH indicated that the type of anemia in Yudong black goats was microcytic anemia.