Low temperature-induced masculinization and histological observation of gonadal differentiation in redfin puffer Takifugu rubripes
ZHOU He 1，2, LI Jia-qi 1, MA Hai-yan 1, LI Ya-juan 1，2, JIANG Zhi-qiang 1，2,LI Xia 1，2, XU Wen 1, JIANG Zhen-hua 1
1.Key Laboratory of Marine Bio-resources Restoration and Habitat Reparation in Liaoning Province, Dalian Ocean University, Dalian 116023, China; 2.Key Laboratory of Mariculture & Stock Enhancement in North China’s Sea, Ministry of Agriculture, Dalian Ocean University, Dalian 116023, China
Abstract: The redfin puffer Takifugu rubripes juveniles at 15，45 and 75 days post hatching were exposed to low water temperature (15 ℃ and 17 ℃) and to normal water temperature of 21 ℃ as a control for 65 days to explore a new method of masculinization without UV radiation and administration of sex hormone. Sex ratio and histology during sex differentiation were investigated in low temperature groups and control group. It was found that there was a negative correlation between water temperature and male ratio (-0.827), and a positive correlation between water temperature and female ratio (0.823), the maximal male ratio of (74.70±2.79)% at 15 ℃, (59.60±3.49)% at 17 ℃, and (51.57±0.06)% at 21 ℃ in the control group. The ovarian cavity, a sign of ovary differentiation, was observed in the 48 days post hatching juveniles in the control group, in 63 days post hatching juveniles in 17 ℃ group and 73 days post hatching juveniles in 15 ℃ group. The gaping spermaduct anlage at nodular gonad, a symbol of testis differentiation, was found in the 68 days post hatching juveniles in the control group, in the 83 days post hatching juveniles in 17 ℃ group and in the 93 days post hatching juveniles in 15 ℃ group. The findings indicated that the cell gonadal division was shown a linear with the temperature increasing in speed, high temperature being beneficial to the gonad development within certain limits.
2015, Vol. 30 
