The optimum dose and period of 17α-methyltestosterone immersion on masculinization of red tilapia(Oreochromis spp.)  

作　　者：Thuchapol Karaket Aisawan Reungkhajorn Pattareeya Ponza 

机构地区：[1]Fisheries Science Program,Department of Agricultural Science,Faculty of Agriculture Natural Resources and Environment,Naresuan University,Phitsanulok,65000,Thailand

出　　处：《Aquaculture and Fisheries》2023年第2期174-179,共6页渔业学报（英文）

摘　　要：This study was carried out to examine the effect of combining factors for immersion technique on masculinization of red tilapia(Oreochromis spp.).Three selected doses(1000,1,500,and 2000μg/L)of 17α-methyltestosterone(17 MT)immersion,2 exposure times(3 and 6 h)once or twice a week,and interaction of these factors were tested.A total of 12 treatment combinations under 3×2×2 factorial experiments in randomized complete block design were conducted to compare with the negative control group(no 17 MT-treated)and positive control group(17 MT-treated feed administration).One hundred red tilapia larvae(14 days post-hatch)were randomly allocated in each treatment and were operated in a 10-L glass jar for 21 days.At the end of the treatment regime,the survival rate was determined.Then,fish were raised in a 150-L glass tank using normal commercial feed for 2 months and sex ratios were determined via the gonad squash technique.None of the immersion treatments tested resulted in a statistically significant(p>0.05)decrease in survival rate.All 17 MT-treated groups produced progenies with a significantly higher(p<0.001)proportion of males than the predicted 1:1 sex ratio.Influences of some factor combinations in the masculinization of red tilapia were observed.The male ratio was significantly affected by the dose-period and dose-frequency treatments(p<0.05).The highest male proportion(95.33%±0.58%)was recorded at 1000μg/L of 17 MT for 6 h once a week which was significantly higher(p<0.05)than other groups.The production cost of the best group was the cheapest(THB0.0066/fish)and decreased from the traditional procedure by about 10.81%.Therefore,this technique could be implemented for decreasing cost and operating process in commercial tilapia farms.

关 键 词：MASCULINIZATION Red tilapia 17α-methyltestosterone Immersion technique 

分 类 号：S917.4[农业科学—水产科学]