The objective of the present study is to analyze sequence variation in the ribosomal 18 S rRNA among Histomonas meleagridis from rare pheasas in Hunan Province. The 18 S rRNA gene was amplified from each sample by PCR, and the 18 S rRNA sequences were aligned using the Clustal X 2.0. The results showed that the lengths of 18 S rRNA sequences were 590 bp. The similarities of the corresponding sequences were more than 99.4% among isolates from Hunan province,and the similarity of Hunan isolates and reference ...