RT - Journal Article T1 - A Study on the Production Possibility of All-Female Triploid Rainbow Trout (Oncorhynchus mykiss) JF - JCPP YR - 2008 JO - JCPP VO - 12 IS - 44 UR - http://jcpp.iut.ac.ir/article-1-885-en.html SP - 269 EP - 278 K1 - Rainbow trout K1 - All-female K1 - Triploid K1 - Sex-reversed male K1 - Heat shock. AB - In order to reduce the adverse effects of sexual maturation on growth and survival of rainbow trout, production possibility of all-female triploid was investigated by means of early heat shock on eggs fertilized by masculinized male’s sperm. Fish ploidy level was determined by erythrocyte size measurement and confirmed by gill nucleolus (NORs) counting as well as chromosome number. Sexual ratios and gonad development were determined by histological studies. Final results showed that progenies produced by mating sex-reversed (masculinized) males and normal females were totally female (100 %). Also, applying early heat shocks (26.5° C lasting 20 min, 20 min after egg fertilization) induced about 80 % triploidy in fishes. All-female triploid, all-female diploid and mixed-sex diploid fishes did not show any significant difference in incubation stages (eyed-stage egg rate, hatching, survival from hatching to active feeding), (P>0.05). Eyed-stage eggs rate, and hatching rate of eyed eggs in mixed-sex triploids were significantly lower than in other treatments (P LA eng UL http://jcpp.iut.ac.ir/article-1-885-en.html M3 ER -