Morphological Characteristic in the Spontaneous Infertile Male Inbred MIJ Rats
Jun-xu LIU1, Yue-hua CAI1, Jing-ge ZHANG2, Shu-xia SONG1, Fu-ying LIU1 (1. Department of Laboratory Animal Science, Hebei Medical University, Hebei Key Lab of Laboratory Animal Science, Shijiazhuang, 050017) (2. Faculty of Forensic Medicine, Hebei Medical University, Shijiazhuang, 050017)
Objective: To investigate the morphological characteristics in the spontaneous infertile male inbred MIJ rats bred in our lab. Methods: The infertility male Wister rats (infertility group, group A), normal Wister male rats from the inbred (control group from the inbred, group B), and growth states of normal male Wister rats(control group, group C) of postnatal 1 month, postnatal 2 months, and postnatal 3 months were observed. The histological changes of testicle and epididymis were observed. Chromosome's G banding was disposed and the types of chromosome were analyzed. Results: Compared with other groups, the weight growth rate was a little slower, and reproductive organs were developmental retardation in group A. The group A of 1st postnatal month had intra-abdominal testes. Compared with other groups, the time of testicular descent, the length of varicosity and gubernaculum testis, the index of testicle and epididymis were significantly decreased in group A, P0.01. The histopathological examination suggested that the seminiferous epithelium became atrophy, and sperm amount in lumens of seminiferous tubules was decreased in group A, but chromosome number and morphology were normal. Conclusion: The spontaneous infertile male MIJ rats showed the characteristics of the delayed testicular descent, testis hypoplasia, and oligozoospermia, and could serve as the better model for the study of male infertility.